Fruit 2

شنبه 10 تیر 1391 05:59 ب.ظ

نویسنده : عسکر اله قلی
Fruit consists of carpels where the ovules (seeds) develop and the ovary wall or pericarp, which may be fleshy (as in apples) or dry and hard (as in an acorn). Some fruits have seeds (mature ovules) enclosed within the ovary (apples, peaches, oranges, squash and cucumbers). The peel of an orange, the pea pod, the sunflower shell, and the skin flesh and pit of a peach are all derived from the pericarp. Other fruit have seeds that are situated on the periphery of the pericarp (corncob, strawberry flesh).


Figure 1. In apples, the ovary wall becomes the fleshy part of the fruit. Notice the small fruit structure in the blossom.


Figure 2. Pome fruit (apple)


Figure 3. Stone fruit (peach)
Fruit Types

Conifers

Conifersare best known for their woody cones, pine cones. Junipers are an example of a conifer with a fleshy cone (Juniper berry). Upon close examination, the overlapping scales can be observed.

Figure 4. Fruit of conifers – Left: Woody seed cone (pine cone). Right: Fleshy seed cone (Juniper berry).
Flowering Plants (Angiosperms)

Depending on flower structure and inflorescence type, fruits may be either simple, aggregate, or multiple.

  • Simple – Fruit formed from one ovary.
  • Aggregate – Fruit formed from a single flower with many ovaries. If not all of the ovaries are pollinated and fertilized, the fruit will be misshapen (raspberry, magnolia).
  • Multiple – Fruit developed from a fusion of separate, independent flowers born on a single structure (mulberry, pineapple, beet seed).


Table 1. Key to Common Fruit Types
1a. Fruit fleshy. -- go to 21b. Fruit dry at maturity. -- go to 6
2a. Fruit simple, that is derived from a flower with a single ovary. -- go to 32b. Fruit derived from a single flower with many ovaries. – Aggregate Fruit(raspberry, magnolia). Note: If not all of the ovaries are pollinated and fertilized, the fur it will be misshapen.2c. Fruit develops form multiple separate flowers in an inflorescence, the fruits coalesce together to form a single “fruit” at maturity. – Multiple Fruit (mulberry, pineapple, beet seed)
3a. Fruit with a single seed enclosed in a hard pit. Theexocarp (outer layer) becomes the thin skin; the mesocarp(middle layer) becomes thick and fleshy; and the endocarp(inner layer) becomes a hard stony pit. – Drupe (peaches, olives, cherries, plums) 3b. Fruit with more than one seed, the seed not enclosed in a hard pit. -- go to 4
4a. Fruit develops from the ovary only. Pulpy fruit from one or more carpels that develops few to many seeds, inner and outer walls fleshy. – Berry (tomatoes, eggplant, blueberries, and grapes)
4a-1. Berries with a leather rind containing oils, enclosing a pulpy juice sack (carpels). –Hesperidium (citrus: oranges, lemons, limes, grapefruit)

4b. Fruits develops from the ovary plus other flower parts (accessory fruits). -- go to 5
5a. Simple fruits with relative hard rind at maturity, fleshy-watery interior with many seeds. – Pepos (cucumbers, melons, and squash)
5b. Simple fruit with several carpels and papery inner wall (endocarp) and fleshy outer wall. – Pomes (apple, pear, quince)
6a. Fruit not splitting at maturity. -- go to 76b. Fruit splitting open at maturity. -- go to 10
7a. One-seed achene fruit (elm, ash) or two-seed fruit (maple) with a wing-like structure formed from the ovary wall.–Samaras

7b. Fruit without wings. – go to 8
8a. One-seeded fruit with hard stony shell (pericarp) surrounding the seed. – Nut (oak, filbert, walnut)
8b. Fruit without hard shell. – go to 9
9a. Simple, one-seeded fruit with a thin seed coat (pericarp) surrounding and adhering tightly to the true seed. – Caryopsis(corn, rice, wheat, and barley)
9b. Simple, one-seeded, thin-wall fruit with seed loosely attached to ovary wall. – Achenes (sunflower)
10a. Fruit from two or more carpels, each with many seeds, splitting along or between carpel lines or forming a cap that comes off or a row of pores near the top. – Capsule (iris, poppy, jimson weed)
10b. Fruit splitting lengthwise along the edge. – go to 11
11a. Fruits from two carpels with a central partition to which the seeds are attached. Splits to expose seeds along central membrane. – Silique or Silicle(mustards)
11b. Fruits not leaving a central partition. – go to 12
12a. Fruit from a single carpel that splits along one suture only. –Follicles (Delphinium)
12b. Fruit from a single carpel usually splits along two sutures. Found in members of the Fabaceae (pea) family. – Legumes Pod (peas, beans)
12c. Fruit formed from two or more carpels that split at maturity to yield one-seeded halves. – Schizocarp



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Fruits

شنبه 10 تیر 1391 05:57 ب.ظ

نویسنده : عسکر اله قلی

Fruits are the containers in which the plant puts its seeds. They are not all fruits as we think of them, but have many different forms. Some are fleshy with parts we like to eat, some are dry, some are heavy and are designed to be dispersed by falling and rolling away from the parent plant, some have wings or fluffy tails to enable them to be caught by the wind to be dispersed.
Fruits are divided into Fleshy Fruits, and Dry Fruits.
Fleshy Fruits can be subdivided again into those formed from a single flower and those formed from a group of flowers. They can have one seed or several seeds in.
Fleshy Fruits formed from a single flower are classified as: Berry, Drupe, Aggregation of Drupes, Pome, Hesperidium. Some authorities also give these separate status: Hep, Pseudocarp, Pepo.
Fleshy Fruits which grow from a group of flowers are: Sorosis, Synconium, Coenocarpium.
Dry Fruits can be divided into those in which the seeds are contained in a seedpod of some sort which opens to release the seeds (called Dehiscent), and those in which there isn't a seedpod which opens (Indehiscent).
Dry Dehiscent Fruits are Follicle, Legume, Silique, Capsule. Some authorities separate these further.
Dry Indehiscent Fruits are: Achene, Nut, Samara, Caryopsis. Some people sub-divide some of these further. There are also Schizocarpic Fruits.
Knowing the type of fruit a plant has might help you to identify it, and might also help you to know when the seeds are ready to harvest.

FLESHY FRUITS
formed from a single flower
BerryA Berry is a single fleshy fruit without a stone, usually containing a number of seeds.
This is a Kiwi Fruit (Actinidia chinensis). Other fruits of this type are: Banana (Musa), Coffee (Coffea arabica), Currant (Ribes), Pasionfruit (Passiflora), Pepper (Capsicum), Tomato (Lycopersicon esculentus).

DrupeA Drupe is a single fleshy fruit with a hard stone which contains the single seed.
This is a Cherry (Prunus avium). Other fruits of this type are: Apricot (Prunus armeniaca), Plum (Prunus x domestica), Coconut (Cocos nucifera), Olive (Olea europaea), Peach (Prunus persica), Sloe (Prunus spinosa).

Aggregation of DrupesAn Aggregation of Drupes is a fleshy fruit, made up of many drupes but formed from a single flower, each drupe containing one seed.
This is a Raspberry (Rubus idaeus). Other fruits of this type are: Loganberry (Rubus), Blackberry (Rubus fruticosus).

PomeA Pome is a fleshy fruit with a thin skin, not formed from the ovary but from another part of the plant. These are sometimes calledAccessory Fruits. The seeds are contained in chambers in the centre of the fruit.
This is an Apple (Malus domestica). Other fruits of this type are: Firethorn (Pyracantha), Hawthorn (Crataegus), Medlar (Mespilus germanica), Pear (Pyrus communis), Quince (Cydonia oblonga).

HesperidiumA Hesperidium is a berry with a tough, aromatic rind.
This is an Orange (Citrus sinensis). Other fruits of this type are all Citrus fruits: Citron (Citrus medica), Grapefruit (Citrus x paradisi), Kumquat (Fortunella), Lemon (Citrus limon), Lime (Citrus aurantifolia).

There are other types of fleshy fruit which some people classify separately. A Hep or Hip is a fleshy fruit containing achenes, as in the Rose (Rosa); aPepo is a fleshy fruit with a leathery skin, formed from an inferior ovary. This type of fruit is found only in members of the Gourd Family (Cucurbitaceae) - Cucumbers (Cucumis melo), Water Melon (Citrullus lanatus), Pumpkin (Cucurbita maxima), and Pseudocarp.

PseudocarpA Pseudocarp is a false fruit, because it does not contain the seeds. The seeds are achenes, on the outside of a fleshy fruit.
This is a Strawberry (Fragaria x ananassa).
FLESHY FRUITS
formed from a group of flowers
There are a few fruits formed from a group of flowers (inflorescence) rather than just one, but which form only one fruit. These are Sorosis, as in the Mulberry (Morus), Syngonium, as in the Fig (Ficus), and Coenocarpium, as in the Pineapple (Ananas).

DRY DEHISCENT FRUITS

FollicleA Follicle is a dry dehiscent fruit which splits on one side only. It may contain one or many seeds.
This is the fruit of a Columbine (Aquilegia). Other fruits of this type are: Delphinium (Delphinium), Larkspur (Consolida), Love in a Mist (Nigella damascena), Milkweed (Asclepias), Peony (Paeonia).
LegumeA Legume is a dry dehiscent pod that splits on two sides.
This is the fruit of a Sweet Pea (Lathyrus odoratus). Other fruits of this type are all in members of the Pea Family (Leguminosae/Fabaceae): Acacia (Acacia), Alfalfa (Medicago sativa), Liquorice (Glycyrrhiza glabra), Flamboyant (Delonix regia), Pea (Pisum sativa), Peanut (Arachis hypogaea), Redbud (Cercis occidentalis), Runner Bean (Phaseolus coccineus), Wisteria (Wisteria).

LomentumA Lomentum is a dry dehiscent fruit, a legume constricted between the seeds.
This is the fruit of a Golden Chain Tree (Laburnum anagyroides). Other fruits of this type are: Sophora (Sophora), Tick Trefoil (Desmodium).

SiliqueA Silique is a dry dehiscent fruit. It is long and thin, splits down the two long sides, and has a papery membrane (the septum) between the two halves.
This is the fruit of a Wallflower (Erysimum cheiri). Other fruits of this type are all in members of the Cabbage Family (Brassicaceae): Aubrieta (Aubrieta x cultorum), Cabbage (Brassica olearacea), Honesty (Lunaria annua), Radish (Raphanus sativus).
A silique which is less than twice as long as broad is called a Silicula.
.CapsuleA Capsule is the most common fruit type. A Capsule is a dry fruit which splits open to release the seeds.
These plants all have fruit capsules: Cotton (Gossypium), Eucalyptus (Eucalyptus), Horse Chestnut (Aesculus hippocastanum), Jimson Weed (Datura), Mahogany (Afzelia), Witch Hazel (Hamamelis).
There are several types of Capsule, depending on how the fruit splits.

Valvate CapsuleA Valvate Capsule is a dry dehiscent fruit in which the tips of the seed capsule split.
This is the fruit of a Campion (Silene). Other fruits of this type are: Jacob's Ladder (Polemonium), Pink (Dianthus), Primrose (Primula).
Porose CapsuleA Porose Capsule is a dry dehiscent fruit, opening with pores or holes around the top.
This is the fruit of a Poppy (Papaver). Other fruits of this type are: Blue Poppy (Meconopsis), Prickly Poppy (Argemone).
Loculicidal CapsuleA Loculicidal Capsule is a dry dehiscent fruit, splitting along the locule (midrib of each ovary).
This is the fruit of Stinking Gladwyn (Iris foetidissima). Other fruits of this type: Evening Primrose (Oenothera), Valotta (Cyrtanthus elatus), and members of the Violet and Lily Families.

Circumscissile CapsuleA Circumscissile Capsule is a dry dehiscent fruit, opening by splitting through the centre of the fruit, so that the top of the capsule lifts off like a lid. An example of this type of fruit is Pimpernel (Anagallis)
A Septicidal Capsule splits along the septa (joints of the ovary) as in the Foxglove (Digitalis).

DRY INDEHISCENT FRUITS
AcheneAn Achene is a single-seeded dry indehiscent fruit in which the seedcoat is not part of the fruit coat.
This is the fruit of a Sunflower (Helianthus annuus). Other fruits of this type are: Buttercup (Ranunculus), Clematis (Clematis), Coreopsis (Coreopsis), Dahlia (Dahlia), English Marigold (Calendula), Zinnia (Zinnia).

CypselaA Cypsela is a single-seeded dry indehiscent fruit that develops from a one part inferior ovary (on the stalk side of the flower). They are sometimes included with Achenes.
This is the fruit of a Dandelion (Taraxacum officinale). Other fruits of this type are found in the same plant family, the Daisy Family (Asteraceae).

NutA Nut is a large single hardened achene.
This is a Chestnut (Castanea sativa). Other fruits of this type are: Acorn (Quercus), Hazel (Corylus avellana), Hickory (Carya).

NutletThis is not a classification that seems to be recognised everywhere, but the Mint Family (Lamiaceae) is a very large plant family, and has a particular type of seed which is not quite any of the normal ones, so I thought it should be included somewhere.
The fruits of this family are single-seeded achene-like nutlets, which are held at the bottom of the calyx.
This is the fruit of a Salvia (Salvia). All members of the Mint Family (Lamiaceae) have this type of fruit.

CaryopsisA Caryopsis is a simple dry indehiscent fruit, like an achene, but with the seedcoat fused with the fruit coat.
This is the fruit of Sweetcorn (Zea). Other fruits of this type are all members of the Grass Family (Poaceae): Barley (Hordeum), Oats (Avena), Rice (Oryza), Rye (Secale), Wheat (Triticum).

SamaraA Samara is an independent dry indehiscent fruit which has part of the fruit wall extended to form a wing (i.e. not a winged seed inside another type of seed pod).
This is the fruit of a Maple (Acer). This is a Schizocarpic Samara, because the fruit splits into its separate Samaras. Other fruits of this type are: Ash (Fraxinus) - also Schizocarpic, Elm (Ulmus



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Inflorescences: How flowers are arranged on the stem

پنجشنبه 8 تیر 1391 06:11 ب.ظ

نویسنده : عسکر اله قلی



Shape Name and Description Example
diagram of single inflorescence shape Single

Sometimes, there is only one flower on each stem, or the flowers are borne so far apart that they cannot be described as being part of the same flowering cluster. They are often large flowers, so do not need the support of other flowers to attract pollinators.


The example is Papaver orientale.

Papaver orientale, an example of single inflorescence shape
diagram of a spike inflorescence shape Spike

A Spike is a group of flowers arising from the main stem, without individual flower stalks (sessile).




The example is Agastache foeniculum.

Agastache foeniculum, example of a spike inflorescence shape
diagram of a raceme inflorescence shape Raceme

A Raceme is a flower spike where the flowers have stalks of equal length, and the tip of the stem continues to grow and produce more flowers. Flowers open from the bottom up.



The example is Linaria vulgaris.

Linaria vulgaris, an example of a raceme inflorescence shape
diagram of a panicle inflorescence shape Panicle

A Panicle is a branched raceme, each branch having a smaller raceme of flowers. The terminal bud of each branch continues to grow, producing more side shoots and more flowers.



The example is Lagerstroemia indica.

Lagerstroemia indica, an example of a panicle inflorescence shape
diagram of a cyme inflorescence shape Cyme

A Cyme is a group of flowers in which the end of each growing point produces a flower, so new growth comes from side shoots and the oldest flowers are at the top.



The example is Geranium pratense.

Geranium, an example of a cyme inflorescence shape
diagram of a whorl or whorled inflorescence shape Verticillaster

A Verticillaster is a whorled inflorescence, where the flowers are borne in rings at intervals up the stem. The tip continues to grow, producing more whorls. This type of inflorescence is common in members of the Deadnettle/Mint Family (Lamiaceae).

The example is Phlomis russelliana.

Phlomis russeliana, an example of a whorl or whorled inflorescence shape
diagram of a corymb inflorescence shape Corymb

A Corymb is a flower cluster where all the flowers are at the same level, with flower stalks of different lengths, forming a flat-topped flower cluster.



The example is Achillea millefolium.

Achillea millefolium, an example of a corymb inflorescence shape
diagram of an umbel or umbellate inflorescence shape Umbel

An Umbel is a flower head in which all the flower stalks are of the same length, so that the flower head is rounded like an umbrella. Many bulbs have this type of flower head.



The example is Nerine bowdenii.

Nerine, an example of an umbel or umbellate inflorescence shape
diagram of a compound inflorescence shape Compound Umbel

A Compound Umbel is an umbel where each stalk of the umbel produces a smaller umbel of flowers. This type of inflorescence is typical of members of the Celery Family (Apiaceae).



The example is Crithmum maritimum.

Crithmum maritimum, an example of a compound inflorescence shape
diagram of a capitulum inflorescence shape Capitulum

A Capitulum is a flower head composed of many separate unstalked flowers close together. This type of inflorescence is typical of the Daisy Family (Asteraceae), where the outer flowers have one conspicuous large petal and the central disk is formed of flowers with smaller petals.

The example is a Senecio species.

Senecio, an example of a capitulum inflorescence shape

Like everything else in nature, these descriptions can only be a general guide to how your flowers might look. There are many variables, even on one plant, and flower clusters are often described as raceme-like cymes, or cymose panicles, or other words that indicate that the flowers do not conform exactly to any one type of inflorescence. The habit of growth may also be affected by growing conditions, so something that produces clear whorls in moist conditions might produce flowers closer together to form a denser spike in drier conditions. I generally refer to anything in long, thin inflorescences as a spike, and anything more rounded as a cluster.

Knowing how a flower head is composed can give you an idea of how many seeds it might produce. Every flower can produce its own seed, so a multiple flower head can theoretically produce many seeds. In practice, particularly in the case of members of the Daisy Family (Asteraceae), not all the seeds develop, which might indicate that pollinators miss some flowers when they are packed closely together.




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BLOSSOM ARRANGEMENT

پنجشنبه 8 تیر 1391 06:09 ب.ظ

نویسنده : عسکر اله قلی


Every flowering plant arranges its blossoms in a consistent, characteristic way. Noticing how a plant's blossoms are arranged can be very helpful when we are trying to identify the plant. But before looking at the different kinds of flower arrangements, we need to become introduced to a good word. Here it is:

inflorescence

An inflorescence is a flowering plant's cluster of flowers. Below, with the pink splatters representing flowers, or blossoms, are diagrams of various common inflorescence types.

inflorescence types

Now let's look at the inflorescences of some real plants. To make the situation like "real life" I take a ten-minute walk and gather what I find, place what I collect onto my scanner screen, and below you see the results.

inflorescence types

At the far left, that's a little Oxalis plant with a single yellow blossom rising above its clover-like leaves. Usually healthy examples of this species of Oxalis bear their flowers in umbels, but this little plant was right along my path and did well to produce a single flower. I'm glad to begin with this ambiguous situation because it reminds us that sometimes plants can be tricky. If this little Oxalis had been healthy enough to produce several flowers, they'd have been arranged in an umbel.

The second-from-the-left is a "head" of White Clover, Trifolium repens. This inflorescence type isn't shown on our diagram. The white head consists of dozens of slender, white flowers, the pedicels (flower stems) of which all join at one place so that the flowers form a sort of sphere. You would call this inflorescence type a globose head, "globose" just meaning spherical, like a globe.

Green Poke fruits in a racemeThe third-from-the-left is part of an inflorescence of the Lyre-leaved Sage, Salvia lyrata. Here only the top two flowers remain. Below these flowers the corollas have fallen off after pollination, leaving only the calyxes surrounding the maturing fruits. You can see that the flowers and calyxes attach to the main stem directly, without possessing any pedicle (flower stem), so this inflorescence type is a spike. If the flowers had pedicles, as shown at the right, the inflorescence would be a raceme. The picture at the right shows a raceme of green, immature Poke fruits (Phytolacca americana).

The second-from-the-right plant is Spring Vetch, Vicia sativa. This plant typically produces two flowers at each node, one flower above each of the opposite leaves. You would say that it has paired flowers. Again, this flower type isn't shown in our diagram and again it shows that just because you have a nice diagram with fancy terms, Mother Nature is often more diverse than we expect her to be...

On the far right, that's False Garlic, Nothoscordum bivalve, with its blossoms in a classic umbel. Well, sometimes these plants do exactly what you want them to...

male & female flowers inside the spathe of an Elephan'ts Ear, Colocasia esculenta var antiquorumSometimes inflorescences are plum mind boggling. For instance, at the right you see the flowering structure of the big-leafed garden plant called Elephant's Ear. The Elephant's Ear belongs to the Arum Family, in which we also find such plants as Jack-in-the-pulpit, Philodendron, Anthurium, Caladium, and other mostly tropical plants.

In the the picture, male and female flowers grow separated from one another on a slender, fingerlike item surrounded by a cylinder of leaflike material. I've cut away one side of the leafy cylinder. On the fingerlike thing inside the cylinder, the green bumps at the bottom are hundreds of female flowers. At the top you see hundreds of cream-colored male flowers. The male and female flowers are separated by many sterile objects called staminodes.

The fingerlike thing bearing the flowers and staminodes is called a spadix and the leafy material forming a cylinder around the spadix is called a spathe. Gardeners who don't understand flower anatomy too well are likely to call the spathe the plant's "flower," but we know that actually in the picture at the right we're seeing hundreds of flowers.




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Inflorescence

پنجشنبه 8 تیر 1391 05:37 ب.ظ

نویسنده : عسکر اله قلی

 Inflorescences

The sum of all flowers of a plant is called inflorescence. Inflorescences exist in many different forms and shapes, so in this week's “Article of the Weel” I want to show the basic and common variants of inflorescences. I'll not show all of them, but only the main types.

So first, let us check out some basic terms. When you look at an inflorescence, you have maybe noticed, that some of them are ending into a terminal flower and others not. In Botany we speak of a monotelic(closed) inflorescence in first case and of a polytelic (opened) inflorescence in the second

It's also makes a different, if an inflorescence only consists of single flowers or in turn are compounded of small inflorescences by itself. First we look at inflorescences, which consist only of single flowers.

I. simple Inflorescences

a) ear: the ear is possible the most simple type of an inflorescence. Here, the flowers are sitting directly into the axil of their bracts. Ears can be found at some species of the Poaceae (e. g. the Genus ofHordeum), but also at the Genus Plantago. A cone is also a variant of an ear.

b) raceme: the raceme is not very different from the ear. The only difference is, that the flowers of a raceme are sitting at the end of a short stalk, growing from the axil of a bract. This type of inflorescence can be found e. g. at the Genus of Viccia.

c) umbel: At the umbel, the flowers also are sitting on a stalk. All stalks starts at the same point of the shoot axis. The bracts of the flowers often forms a such called involucrum. So the whole inflorescence looks like a umbrella. Umbels are the typical character for the Apiaceae family, which is also calledUmbeliferaceae. Be careful, because sometimes, a raceme is formed like an umbrella (e. g. at Capsella bursa-pastoris L.), but this are no real umbels, because here the stalks are not starting at the same point.

Sometimes, an umbel consists of smaller umbels. This is a double-umbel (d)

e) & f): catkin: a catkin in basically no more than an inverted and hanging ear or raceme. This type of inflorescence is typical for many genera of our native trees like Alnus, Populus or Salix.

note: in this picture the small bracts of 
the spadix and the head 1 has not be draw

g) spadix: A spadix is a special type of an ear, but here, the floral axis is thickened and cylindrical. Spadices can be found e.g. at Zea mays L. (corn) and the most species from the Araceae. They are also typical for the Genus Typha (bullrush or corndog grass) of the Typhaceae.

e) head 1: The first type of the head-formed inflorescence is similar to the spadix. The transition is fluently indeed. The flora axis is also thickened but more jolted. This inflorescence is typical for the TrifoliumGenus (e. g. Trifolium medium ssp. medium L. in this Blog)

f) head 2: The second head inflorescence is the characteristic inflorescence of the Asteraceae family (with species like common daisy, common dandelion or the sun flower). Here the floral axis is compressed even more than the first head type. The flowers are sitting directly at this floral axis and their bracts are forming a involucrum.

II. compounded inflorescences

O.k. Folks, now it becomes complicated. In the previous inflorescences we always have a single flower per bract. But sometimes, a inflorescence is multi-branched, that means instead of a flower it has smaller floral axis, growing out from the axial of the bracts.

In this case it depends on how the inflorescence is branched. First, we have two basic types again: the panicle and the cyme.


a) panicle: At a panicle, a new floral axis grows from a single bract. This axis can be branched by itself. The branching doesn't follow a strict scheme and flowers can grow everywhere. A panicle is always monotelic.

b) cyme: If the successive branches follows a scheme, we speak of a cyme. If there is only one new axis per branching, we call it a monochasium. With two new axis per branching, we called dichasium.

Now we subdivide the monochasial and dichasial cymes into three types again.



c) thyrse: A thyrse is simply a inflorescence with dichasial cymes as branches. The inflorescence of Aesculus hippocastanum L. (conker tree) is a good example for a thyrse

d) depranium: A depranium is a monochasial cyme. Here, the floral axis are helical applied towards the main axis.

e) rhipidium: The rhipidium is basically the opposite of the depranium. The successive floral axis grow in a zigzag pattern. The inflorescence of the tomato is e. g. a rhipidium


An inflorescence may be defined as a cluster of flowers,
all flowers arising from the main stem axis or peduncle:


1. Cyme


2. Umbel


3. Inflorescence Types



4. Catkin: Inflorescence With Unisexual Flowers

Left: Male (staminate) catkin from the white mulberry (Morus alba), a fruitless variety commonly planted as a shade tree in southern California. Right: An individual male flower containing four stamens, each with an anther and a filament. At the base of each filament is a fleshy green sepal. Male trees are known as "fruitless mulberry" because they do not produce messy fruits that stain clothing and walkways. Since mulberries are wind-pollinated, male trees produce copious pollen which can raise havoc with hay-fever sufferers.

Female catkin from a variety of black mulberry (Morus nigra). Mulberry flowers are produced in a catkin, with male and female catkins on different trees. Male flowers have four stamens while female flowers consist of single pistil tightly enveloped by four inconspicuous sepals. Each carpel or pistil (also referred as a gynoecium) consists of a forked stigma, a short style and a spherical ovary. Each ovary (carpel) becomes a drupelet and the ripened cluster of drupelets (syncarp) is called a multiple fruit. In the aggregate fruit of a blackberry, all the drupelets of the cluster (syncarp) come from a single flower. Seedless, parthenocarpic fruits may be produced without pollination by male trees.


5. Spadix: Inflorescence Of The Arum Family (Araceae)

The spadix is the characteristic inflorescence of the remarkable arum family (Araceae). It consists of a thickened, fleshy axis (spike) bearing clusters of sessile, apetalous, unisexual flowers. The small unisexual flowers are packed together along the lower region of an erect, phallus-like central spike, typically with male flowers above the female. The upper region of the spadix is usually devoid of flowers. Male (staminate) flowers consist of numerous stamens packed together, while female (pistillate) flowers consist of numerous individual pistils. Individual flowers are reduced to a single stamen or pistil (gynoecium). The spadix emerges from a vase-shaped or funnel-like modified leaf or spathe which is often brightly colored. The spadix of some arums emits a putrid odor that attracts carrion flies for pollination.

The spadix of some aroids produces a remarkable amount of heat during cold weather. In fact, the temperature of the spadix can be up to 30 degrees Celsius above a cool air temperature of 10 degrees Celsius. This may stimulate the activity of pollinator insect visitors and help to vaporize the stench of the flowers. The heat mechanism may involve male flowers packed around the spadix. In some species in which the upper part of the spadix is sterile (flowerless), the heat mechanism appears to be in the cells of this sterile tissue. Like heat-producing tissue in mammals, the cells in these flowers rapidly oxidize lipids and carbohydrates, thus releasing heat. Heat production in aroids is discussed in a fascinating article by R.S. Seymour in Scientific American, March 1997.

The bizarre Malaysian Amorphophallus paeoniifolius. An enlarged, inflated, flower-bearing spadix protrudes from the vase-shaped spathe. Clusters of yellow male flowers (stamens) can be seen above the whitish stigmas of female flowers (pistils).


Inflorescence Definitions

Note: Inflorescences with youngest flower at the end of the main axis (rachis) are called "indeterminate" (i.e. terminal bud continues to produce new flowers). Inflorescences with oldest flower at the end of the main axis are called "determinate" (i.e. terminal bud stops growing and lateral flowers are produced from axillary buds.)

  • Solitary: A single flower on a caulescent or acaulescent stem.

  • Spike: Unbranched inflorescence with sessile flowers (no pedicels).

  • Raceme: Unbranched inflorescence with flowers on pedicels.

  • Panicle: A branched or compound raceme (i.e. main rachis with branches bearing flowers on pedicels).

  • Corymb: Flat-topped inflorescence with youngest flowers at the end of main axis or rachis.

  • Cyme: Flat-topped inflorescence with oldest flowers at the end of main axis. [Includes simple, compound and scorpioid cymes.]

  • Umbel: Flat-topped inflorescence with all the pedicels arising from a common point. [Includes simple and compound umbels.]

  • Catkin or Ament: A spike-like inflorescence of unisexual, apetalous flowers, often pendent and falling as a unit. This is the typical inflorescence of willow (Salix), cottonwood (Populus), oak (Quercus), alder (Alnus) and birch (Betula). All these species belong to a polyphyletic group of angiosperm families known as the Amentiferae.

  • Spadix: A thick, fleshy spike of unisexual, apetalous flowers, often surrounded by a vase-shaped or funnel-like modified leaf or spathe which is often brightly colored. The male flowers are typically clustered above the female flowers on an erect, phallus-like spike. This is the characteristic inflorescence of the arum family (Araceae).

  • Spathe: A leaf-like bract or sheath that envelops an inflorescence. In the arum family (Araceae), the vase-shaped or funnel-like spathe is often brightly colored. The most remarkable spathe surrounds the inflorescence (spadix) of the corpse flower (Amorphophallus titanum), so named because of the stench of the blossom. Native to equatorial tropical rain forests of Sumatra, Indonesia, this amazing plant attracts flies for pollination. At its maximum development, the spadix may be 8 feet tall (2.4 m) with a huge vase-shaped, pleated spathe over 4 feet (1.2 m) tall and 12 feet (4 m) in circumference. The deciduous spathe of palm inflorescences may be several feet long and quite woody. In fact, the fallen spathes of coconut palms (Cocos nucifera) are boiled, dried and waxed to produce a beautiful boat-shaped bowl.

Spathe bowls from the coconut palm (Coco nucifera). Fallen spathes are boiled, dried and waxed to produce these sleek, shiny black bowls



Inflorescence Types




Spike an elongate, unbranched, indeterminate inflorescence with sessile flowers.
Spikelet a small spike, characteristic of grasses and sedges.
Raceme an elongate, unbranched, indeterminate inflorescence with pedicelled flowers.
Panicle a branched raceme.
Corymb a flat-topped raceme with elongate pedicels reaching the same level.
Compound Corymb a branched corymb.
Umbel a flat-topped or rounded inflorescence with the pedicels originating from a common point. Umbels can be determinate or indeterminate.
Compound Umbel a branched umbel, with primary rays arising from a common point, and secondary umbels arising from the tip of the primary rays.
Capitulum
(or head)
a dense vertically compressed inflorescence with sessile flowers on a receptacle and subtended by an involucre of phyllaries, characteristic of the Asteraceae. Heads can be determinate or indeterminate.
Thyrse a many-flowered inflorescence with an indeterminate central axis and many opposite, lateral dichasia; a mixed inflorescence, with determinate and indeterminate shoots



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آخرین ویرایش: شنبه 10 تیر 1391 07:40 ب.ظ

Plant development

پنجشنبه 1 تیر 1391 08:22 ب.ظ

نویسنده : عسکر اله قلی

Plant Development 3787
Photo by: matttilda

Plant development is an umbrella term for a broad spectrum of processes that include: the formation of a complete embryo from a zygote ; seed germination; the elaboration of a mature vegetative plant from the embryo; the formation of flowers, fruits, and seeds; and many of the plant's responses to its environment. Plant development encompasses the growth and differentiation of cells, tissues, organs, and organ systems. Plant development shares many similarities with developmental processes in animals, but the fact that plants are nonmotile, photosynthetic organisms requires certain novel developmental processes in addition to the common ones.

Embryo and Seed Development

Embryogenesis, the formation of a multicellular embryo from a single-celled zygote, is one of the most dramatic and best-characterized aspects of plant development. Four key developmental processes take place during embryogenesis. First, the zygote expresses apical -basal polarity, meaning that the apical and basal ends of the zygote cell differ structurally and biochemically. When the zygote divides, it typically divides asymmetrically, giving rise to a small apical cell with dense cytoplasm and a large basal cell with watery cytoplasm. Although these two cells have identical nuclei, their fates differ dramatically. The apical cell gives rise to the embryo itself, while the basal cell gives rise to a short-lived structure called a suspensor and the tip of the root system. The progeny of the apical cell grow and divide to form a

Embryo formation begins with cell division that establishes the apical-basal (top-bottom) axis. Further divisions elaborate on this basic plan, finally forming the cotyledons (seed leaves), as well as the apical meristems of root and shoot.
Embryo formation begins with cell division that establishes the apical-basal (top-bottom) axis. Further divisions elaborate on this basic plan, finally forming the cotyledons (seed leaves), as well as the apical meristems of root and shoot.
spherical mass of cells, the globular-stage embryo. Second, differential growth within the globular embryo gives rise to the "heart" stage embryo, the earliest stage when the precursors of cotyledons , root, and stem can be recognized. This key embryogenic process is called organogenesis. Third, distinctive planes of cell divisions bring about histogenesis , the process by which cells within embryonic cotyledons, root, and stem acquire different shapes, forming the precursors of the plant tissue systems. Last, the apical meristems of the shoot and root systems are formed at the apical and basal ends of the embryo.

After an embryo has reached full size, developmental changes continue to occur at the cellular level. Embryonic cells, particularly those of the cotyledons, begin to synthesize and store the proteins , lipids , and starch that will provide the energy and basic building blocks for germination and seedling growth. Next, the embryo begins to desiccate, sometimes losing up to 80 percent of its previous water content, and enters a phase of dormancy. Development and metabolism are arrested in dormant embryos, and seeds containing dormant embryos can survive for many years (sometimes centuries) and withstand extreme temperatures and drought.

Plant hormones are important regulators of embryogenesis and seed dormancy. The hormones auxin, gibberellic acid, and cytokinin all stimulate growth and are present in the embryo during the stages of embryogenesis. As the embryo matures, these hormones are degraded and abscisic acid is synthesized by the embryo. Abscisic acid provides a developmental signal for the embryo to initiate the synthesis of storage compounds and to undergo desiccation . Abscisic acid is present in dormant seeds and is thought to play an important role in maintaining seed dormancy.

Germination and Seedling Development

Embryo development and metabolism resume upon seed germination. Given the right combination of water availability, temperatures, and light, the desiccated seed begins to take up water and the embryo begins to grow and metabolize again. Some species have specific requirements for germination; for instance, many temperate zone tree species require several weeks of temperatures of 4 degrees Celsius (39.2 degrees Fahrenheit) or less in

The root is the first portion of the plant to emerge during germination. Growth of the stem behind the cotyledons forms a "hook" that emerges from the soil, followed by emergence of the cotyledons, which begin to photosynthesize to feed further growth.
The root is the first portion of the plant to emerge during germination. Growth of the stem behind the cotyledons forms a "hook" that emerges from the soil, followed by emergence of the cotyledons, which begin to photosynthesize to feed further growth.
order to germinate. Other species require low levels of light in order to germinate. Once germination is initiated, the embryo follows a typical pattern of development. In many plants, the preformed embryonic root elongates first, forcing its way out of the seed coat and into the soil. Next, the embryonic stem, usually the part below the attachment of the cotyledons (the hypocotyl), elongates. Once the hypocotyl has carried the cotyledons into the light, they expand, providing a broad surface for photosynthesis.

Environmental factors and their translation into hormonal signals are important for seedling development. For instance, germination in the dark results in developmental events that help the seedling push its way through the soil into the light. The hypocotyl elongates quickly and maintains a "hook" near its tip that protects the cotyledons and shoot apical meristem region. Cotyledon expansion is suppressed so that they are not damaged as they are pulled through the soil. In contrast, if the same seeds germinate in the light, the hypocotyl hardly elongates at all and does not form a hook, while the cotyledons quickly expand. The hormone gibberellic acid plays an important role in seed germination and early seedling growth. Gibberellic acid induces the synthesis of enzymes required for the metabolism of stored foods, thus providing energy for seedling growth. Gibberellic acid also induces cell division and cell expansion in dark-grown hypocotyls, maintaining their rapid growth through the soil.

Apical Meristems and Development

The early stages of germination simply involve the enlargement of the root, hypocotyl, and cotyledons that were preformed in the embryo. Postembryonic development, however, is focused on the apical meristems. The shoot apical meristem is the source of all the leaves, stems, and their component cells formed during the lifetime of the plant. The meristem itself is composed of a small population of perpetually embryonic (meristematic) cells. These cells grow and divide, giving rise to new cells, but never mature themselves. Thus there is always a source of new cells at the tip of the shoot. The root tip has a similar population of meristematic cells that gives rise to all root tissues. Both of these meristems are characterized by an indeterminate growth pattern: one that is not finite, but, in theory at least, could continue throughout the lifetime of the plant.

Apical meristems are involved in several distinct developmental processes. The meristems are the location of cell proliferation and thus the source of all new cells in the shoot and root systems. The regions below the meristems are the sites of active growth, as new shoot and root tissue rapidly expands. The shoot apical meristem plays a role in organogenesis, the formation of new leaves and axillary buds in a precise spatial pattern. In contrast, the root apical meristem is not involved in organogenesis; lateral roots are initiated by pericycle cells, which are themselves derived from the meristem, usually several centimeters away from the meristem. The apical meristems also play a role in histogenesis by giving rise to cells that undergo distinct patterns of differentiation to form the specialized tissue types of the shoot and root. While the embryo initially gives rise to the precursors of dermal, ground, and vascular tissues (protoderm, ground meristem, and procambium, respectively), these tissue precursors continue to be formed by the apical meristems and represent the first stages of cell and tissue differentiation.

Structure of root and shoot apical meristems.
Structure of root and shoot apical meristems.

Cell Growth and Cell Division

Growth is defined as an irreversible increase in mass that is typically associated with an increase in volume. Plant cell growth is associated with meristems and must be carefully regulated in order for organogensis and histogenesis to occur in the appropriate patterns. The plant regulates growth by regulating the extensibility of its cell walls. A cell that has nonextensible cells walls can take up some water, but eventually the physical pressure of the water inside the cell pressing out on the cell wall (the turgor pressure) prevents the entry of additional water and any further change in volume. In contrast, a cell that has extensible cell walls can take up a substantial volume of water and thus increase in size. Turgor pressure that would otherwise prevent water entry momentarily decreases because the walls keep stretching.

Typically cell growth occurs in small increments: (1) wall extensibility increases, reducing turgor pressure; (2) reduced turgor pressure allows water to enter the cell, increasing cell volume; (3) wall extensibility decreases, allowing the cell to build up turgor and preventing further water entry; and (4) the cell undergoes a cycle of synthesis of cytoplasmic and wall components, adding to the cell's mass. This cycle of incremental growth is repeated many times until the cell reaches its final size.

The plant hormones auxin and gibberellin are produced in the vicinity of the apical meristems and usually act in concert to induce cell growth. Both hormones regulate wall extensibility, but carry out this function in different ways. Auxin induces the activity of cell membrane H +adenosine triphosphatase (ATPase) molecules. Proton (H + ) extrusion lowers the pH of the cell wall, thus activating the cell wall enzyme expansin. Expansin cleaves the hydrogen bonds between two cell wall components: The cellulose microfibrils and the hemicellulosemolecules that link adjacent cellulose microfibrils. Breakage of these bonds allows these structural wall components to reposition themselves farther apart, increasing wall extensibility. Gibberellic acid, on the other hand, stimulates the activity of another cell wall enzyme called xyloglucan endotransglycosylase (XET). Xyloglucans are a type of hemicellulose that is cleaved by the XET enzyme. Breakage of the

The hormones auxin and gibberellin each promote cell expansion by loosening the bonds between adjacent cell wall molecules. Each hormone acts on a different molecular target.
The hormones auxin and gibberellin each promote cell expansion by loosening the bonds between adjacent cell wall molecules. Each hormone acts on a different molecular target.
hemicellulose molecules also allows the cellulose microfibrils to move farther apart, increasing wall extensibility.

Cell division and cell growth are often tightly linked. When the rate of cell division is balanced by cell growth, as in the apical meristems, average cell size does not increase. As the meristem grows away from earlier formed cells, the ratio of growth to division increases, resulting in overall cell enlargement. As the tissues mature further, cell division ceases completely, giving rise to zones of pure cell enlargement where most of the visible growth of the plant occurs. This relationship between division and growth, coupled with observations of the predictable planes of cell division during histogenesis, indicates that cell division is carefully regulated during plant development.

Molecules called cyclin-dependent kinases (CDKs) are key regulators of cell cycling (including cell division) in plants. CDKs are activated by association with a regulatory subunit called a cyclin and by phosphorylation and dephosphorylation events. The plant hormone cytokinin appears to regulate the cell cycle by interacting with the CDKs. Cytokinins enhance the synthesis of the cyclin subunits that are required for the cell to enter the deoxyribonucleic acid (DNA) synthesis phase of the cell cycle. Cytokinins also enhance the CDK dephosphorylation step that is required for the cell to progress into mitosis . Both of these processes are inhibited by the hormone abscisic acid; thus a "developmental tug-of-war" occurs between a division-enhancing hormone and a division-suppressing hormone. The delicate balance between them determines the rate of cell division and this type of interaction is probably typical of the hormonal regulation of many aspects of plant development.

Differentiation

Differentiation is the process whereby cells, tissues, and organs become different from each other and from their precursors. The concept can be applied to organogenesis since cotyledons, foliage leaves, sepals , and petals may all develop from similar appearing precursors, the leaf primordia. As these organs mature, they become different from each other in size, shape, and the development of distinctive cell types. For instance, the epidermis tissue of petals is sharply differentiated from that of cotyledons, foliage leaves and sepals that are photosynthetic organs. Correlated with a photosynthetic function, the epidermis of these organs is made up of flat, transparent cells that allow the penetration of light into internal tissues. Specialized guard cells that allow CO 2 to enter the leaf are also present. In contrast, the epidermal cells of petals contain brightly colored carotenoid or anthocyanin pigments. These cells also have a papillate shape that imparts a velvetlike sheen to the petal surface. Since petals carry on minimal photosynthesis, they often lack guard cells.

The process of differentiation is best understood on a cellular level. For instance, guard cells are highly specialized epidermal cells. Early in the development of a leaf, protodermal precursor cells undergo a distinctive pattern of cell divisions. At first the cell divisions are asymmetric, producing one large and one small derivative. The large derivative stops dividing and differentiates as an unspecialized epidermal cell, while the small derivative undergoes another asymmetric division. At an unknown stop signal, the small derivative undergoes a symmetric division, giving rise to two equal sized cells that become the guard cells. Unlike their plain neighbors, these cells develop a distinctive kidney shape, unevenly thickened cell walls, large, conspicuous chloroplasts, and finally form a pore (the stomatal aperture) between them.

Uniqueness of Plant Development

Although plants share many features of development with animals such as apical-basal polarity, regulation of the balance between cell growth and cell division, formation of distinctive patterns of organs, cells and tissues, and differentiation, some aspects of development are unique to plants. Among these are:

  • • The formation and maintenance of the perpetually embryonic regions, the apical meristems. The meristems have an indeterminate growth pattern that result in the occurrence of growth, organogenesis, and histogenesis throughout the life of the plant.
  • • Plant cells have rigid cell walls that prevent cell movement. Thus organogenesis and histogenesis must occur through differential growth and regulation of the planes of cell division. Cell-cell communication is important in plant development, but cell recognition is likely less important than it is in animals since plant cells keep the same neighbors throughout their life.
  • • Plant cells are totipotent; that is, able to differentiate as a different cell type if given the appropriate stimulus. Totipotency is likely a reflection of the plant's sedentary lifestyle. Plants can't escape predators and other kinds of damage, but they can readily repair wounds and reconnect vascular strands by differentiating the appropriate cell types.
    Guard cells regulate passage of gasses into and out of the leaf through pores in the surface. Guard cells form by a series of cell divisions from undifferentiated protoderm, including a final symmetric division that forms the two identical cells.
    Guard cells regulate passage of gasses into and out of the leaf through pores in the surface. Guard cells form by a series of cell divisions from undifferentiated protoderm, including a final symmetric division that forms the two identical cells.



Read more: Plant Development - Biology Encyclopedia - cells, body, function, process, system, different, organisms, DNA, organs, cycle http://www.biologyreference.com/Ph-Po/Plant-Development.html#b#ixzz1yRYMqtAE




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Plant life cycles

سه شنبه 30 خرداد 1391 06:16 ب.ظ

نویسنده : عسکر اله قلی

 

Based on its life cycle, a plant is classified as an annual, biennial, or perennial.

Annuals

An annual, such as a zinnia, completes its life cycle in 1 year. Annuals are said to go from seed to seed in 1 year or growing season. During this period, they grow, mature, bloom, produce seeds, and die. There are both winter and summer annual weeds, and understanding a weed's life cycle is important in controlling it. Summer annuals complete their life cycle during spring and summer; most winter annuals complete their growing season during fall and winter.


 

BiennialsA biennial requires all or part of 2 years to complete its life cycle. During the first season, it produces vegetative structures (leaves) and food storage organs. The plant overwinters and then produces flowers, fruit, and seeds during its second season. Swiss chard, carrots, beets, Sweet William, and parsley are examples of biennials.

Sometimes biennials go from seed germination to seed production in only one growing season. This situation occurs when extreme environmental conditions, such as drought or temperature variation, cause the plant to pass rapidly through the equivalent of two growing seasons. This phenomenon is referred to as bolting. Sometimes bolting occurs when biennial plant starts are exposed to a cold spell before being planted in the garden.


 

PerennialsPerennial plants live more than 2 years and are grouped into two categories: herbaceous perennials and woody perennials. Herbaceous perennials have soft, nonwoody stems that generally die back to the ground each winter. New stems grow from the plant's crown each spring. Trees and shrubs, on the other hand, have woody stems that withstand cold winter temperatures. They are referred to as woody perennials.


 




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Monocotyledonous Plant تک لپه ایها

سه شنبه 30 خرداد 1391 11:17 ق.ظ

نویسنده : عسکر اله قلی
Selected Monocotyledonous Plant Orders & Their Families

Alismatales
Alismataceae, Butomaceae, Limnocharitaceae

Hydrocharitales
Hydrocharitaceae

Najadales
Aponogetonaceae, Najadaceae, Potamogetonaceae

Commelinales
Commelinaceae

Eriocaulales
Eriocaulaceae

Restionales
Restionaceae

Juncales
Juncaceae

Cyperales
Cyperaceae, Poaceae

Typhales
Sparganiaceae, Typhaceae

Bromeliales
Bromeliaceae

Zingiberales
Cannaceae, Costaceae, Heliconiaceae, Lowiaceae, Marantaceae, Musaceae, Strelitziaceae, Zingiberaceae

Arecales
Arecaceae

Cyclanthales
Cyclanthaceae

Pandanales
Pandanaceae

Arales
Araceae, Lemnaceae

Liliales
Agavaceae, Dioscoreaceae, Haemodoraceae, Hypoxidaceae, Iridaceae, Liliaceae (includes former Amaryllidaceae), Pontederiaceae, Smilacaceae, Taccaceae, Xanthorrhoeaceae

Orchidales
Orchidaceae


Part 2
Selected Monocotyledonous Plant Families & Their Genera

Agavaceae - Century Plant Family
Agave (Century Plant), Beaucarnea (Ponytail Palm), Beschorneria, Calibanus, Cordyline (Cabbage Tree), Dasylirion (Sotol), Doryanthes (Spear Lily), Dracaena (Dragon Tree), Furcraea, Hesperaloe (Red Yucca), Manfreda, Nolina (Bear Grass), Phormium (New Zealand Flax), Polianthes (Tuberose), Sansevieria (Mother-in-Law's Tongue), Yucca

Alismataceae - Water Plantain Family
Alisma (Water Plantain), Sagittaria (Swamp Potato)

Amaryllidaceae - Amaryllis Family - Included within Liliaceae.
Agapanthus (Lily of the Nile), Amaryllis (Belladonna Lily), Clivia, Crinum, Eucharis (Amazon Lily), Galanthus (Snowdrop), Habranthus (Copper Rain Lily), Haemanthus (Blood Lily), Hippeastrum (Amaryllis), Hymenocallis (Tropical Spider Lily), Leucojum (Snowflake), Lycoris (Red Spider Lily), Narcissus (Daffodil), Nothoscordum (False Garlic), Sprekelia (Aztec Lily), Sternbergia (Lily of the Field), Tulbaghia (Society Garlic), Zephyranthes (Rain Lily)

Aponogetonaceae - Aponogeton Family
Aponogeton (Cape Pondweed)

Araceae - Arum Family
Acorus (Sweet Flag), Aglaonema (Chinese Evergreen), Alocasia (Elephant's Ear), Amorphophallus (Leopard Palm), Anthurium, Arisaema (Jack in the Pulpit), Arum (Solomon's Lily), Caladium, Calla, Colocasia (Taro), Dieffenbachia (Dumb Cane), Epipremnum (Pothos), Monstera (Split-Leaf Philodendron), Nephthytis, Philodendron, Pistia (Water Lettuce), Pothos, Scindapsus, Spathiphyllum, Syngonium (Arrow Head Vine), Xanthosoma (Malanga, Yautia), Zamioculcas, Zantedeschia (Calla Lily)

Arecaceae (Palmae) - Palm Family
Acoelorrhaphe (Paurotis Palm), Brahea, Butia (Pindo Palm), Chamaedorea (Parlor Palm), Chamaerops (Mediterranean Fan Palm), Chrysalidocarpus (Areca Palm), Cocos (Coconut Palm), Guihaia (Karst Palm), Howea (Kentia Palm), Jubaea (Chilean Wine Palm), Livistona (Fan Palm), Nannorrhops (Afghan Palm), Neodypsis (Triangle Palm), Phoenix (Date Palm), Rhapidophyllum (Needle Palm), Rhapis (Lady Palm), Sabal (Palmetto), Serenoa (Saw Palmetto), Syagrus (Queen Palm), Trachycarpus (Windmill Palm), Washingtonia (Fan Palm)

Bromeliaceae - Bromeliad Family
Aechmea (Urn Plant), Ananas (Pineapple), Billbergia (Vase Plant), Bromelia (Heart of Flame), Cryptanthus (Earth Star), Dyckia, Guzmania, Hechtia, Neoregelia, Puya, Tillandsia (Ball Moss), Vriesia

Butomaceae - Flowering Rush Family
Butomus (Flowering Rush), Limnocharis

Cannaceae - Canna Family
Canna

Commelinaceae - Spiderwort Family
Commelina (Dayflower), Commelinantia, Dichorisandra (Blue Ginger), Rhoeo (Moses in a Boat), Setcreasea (Purple Wandering Jew), Tinantia (Spotted Wandering Jew), Tradescantia (Spiderwort), Zebrina (Wandering Jew)

Costaceae - Spiral Flag Family
Costus (Spiral Flag), Dimerocostus, Monocostus, Tapeinochilus (Torch Ginger)

Cyclanthaceae - Panama Hat Palm Family
Carludovica (Panama Hat Palm), Cyclanthus

Cyperaceae - Sedge Family
Cladium (Saw Grass), Carex (Sedge), Cyperus (Papyrus), Eleocharis (Chinese Water Chestnut), Scirpus (Bulrush)

Dioscoreaceae - Yam Family
Dioscorea (Yam)

Eriocaulaceae - Pipewort Family
Eriocaulon (Pipewort)

Haemodoraceae - Bloodwort Family
Anigozanthos (Kangaroo Paw)

Heliconiaceae - Heliconia Family
Heliconia

Hydrocharitaceae - Frog's-Bit Family
Elodea (Water Weed), Hydrilla, Hydrocharis (Frog's-Bit), Vallisneria (Eel Grass)

Hypoxidaceae - Star Grass Family
Curculigo (Palm Grass), Hypoxis (Star Grass), Rhodohypoxis

Iridaceae - Iris Family
Acidanthera (Peacock Orchid), Alophia, Babiana (Baboon Flower), Belamcanda (Leopard Flower), Crocosmia (Montebretia), Crocus, Dierama (Wandflower), Dietes (African Iris), Freesia, Gladiolus, Iris, Ixia (Corn Lily), Lapeirousia, Moraea (Butterfly Iris), Nemastylis (Celestial), Neomarica (Walking Iris), Sisyrinchium (Blue-Eyed Grass), Sparaxis (Wandflower), Tigridia (Tiger Flower), Tritonia, Watsonia

Juncaceae - Rush Family
Juncus (Rush), Luzula (Wood Rush)

Lemnaceae - Duckweed Family
Lemna (Duckweed)

Liliaceae (see also Amaryllidaceae) - Lily Family
Allium (Onion), Aloe, Anthericum (Spider Plant), Asparagus, Aspidistra (Cast Iron Plant), Bowiea (Climbing Onion), Bulbine, Camassia (Camas), Chionodoxa (Glory of the Snow), Chlorophytum (Spider Plant), Colchicum (Autumn Crocus), Convallaria (Lily of the Valley), Eremurus (Desert Candle), Erythronium (Dog Tooth Violet), Eucomis (Pineapple Lily), Fritillaria, Galtonia (Summer Hyacinth), Gloriosa, Hemerocallis (Daylily), Hosta, Hyacinthus (Hyacinth), Kniphofia (Red Hot Poker), Lachenalia (Cape Cowslip), Lapageria (Chilean Bellflower), Ledebouria, Lilium (Lily), Liriope, Muscari (Grape Hyacinth), Ophiopogon (Monkey Grass), Ornithogalum (Star of Bethlehem), Paris, Polygonatum (Solomon's Seal), Rohdea (Chinese Sacred Lily), Ruscus (Butcher's Broom), Scilla (Squill), Smilacina (Solomon's Seal), Tricyrtis (Toad Lily), Trillium, Tulipa (Tulip), Veltheimia, Veratrum (False Hellebore)

Limnocharitaceae - Limnocharis Family
Limnocharis

Lowiaceae - Orchidantha Family
Orchidantha

Marantaceae - Arrowroot Family
Calathea (Peacock Plant), Maranta (Prayer Plant), Thalia

Musaceae - Banana Family
Ensete (Abyssinian Banana), Musa (Banana), Musella (Golden Mountain Banana)

Najadaceae - Naiad Family
Najas (Water Nymph)

Orchidaceae - Orchid Family
Bletilla (Hardy Orchid), Cattleya, Cymbidium, Dendrobium, Phalaenopsis (Moth Orchid), Oncidium (Dancing Lady), Spiranthes (Ladies's Tresses), Vanda, Vanilla, etc.

Pandanaceae - Screw Pine Family
Freycinetia, Pandanus (Screw Pine)

Poaceae (Gramineae) - Grass Family
Andropogon (Bluestem), Arundinaria (Cane), Arundo (Giant Reed), Avena (Oats), Bambusa (Bamboo), Bouteloua (Grama Grass), Buchloe (Buffalo Grass), Chasmanthium (Inland Sea Oats), Chimonobambusa, Cortaderia (Pampas Grass), Cymbopogon (Lemon Grass), Cynodon (Bermuda Grass), Dendrocalamus, Elymus (Wild Rye), Hilaria, Hordeum (Barley), Miscanthus (Maiden Grass),
Muhlenbergia (Muhly Grass), Oryza (Rice), Otatea (Mexican Weeping Bamboo), Panicum (Switch Grass), Paspalum (Bahia Grass), Pennisetum (Fountain Grass), Phalaris (Canary Grass), Phragmites (Reed), Phyllostachys (Bamboo), Poa (Bluegrass), Pseudosasa (Arrow Bamboo), Saccharum (Sugar Cane), Sasa, Schizachyrium (Little Bluestem), Secale (Rye), Semiarundinaria, Setaria (Bristle Grass), Sorghastrum (Indian Grass), Sorghum, Spartina (Marsh Grass),Sporobolus (Dropseed), Stenotaphrum (St. Augustine Grass), Stipa (Feather Grass), Triticum (Wheat), Vetiveria (Vetiver), Zea (Corn), Zizania (Wild Rice), Zoysia

Pontederiaceae - Pickerel Weed Family
Eichhornia (Water Hyacinth), Pontederia (Pickerel Weed)

Potamogetonaceae - Pond Weed Family
Potamogeton (Pond Weed)

Restionaceae - Restio Family
Askidiosperma, Cannomois, Chondropetalum (Cape Thatching Reed), Elegia, Ischyrolepis, Restio (Cape Reed), Rhodocoma, Thamnochortus (Thatching Reed)

Smilacaceae - Greenbrier Family
Smilax (Greenbrier)

Sparganiaceae - Bur Reed Family
Sparganium (Bur Reed)

Strelitziaceae - Strelitzia Family
Phenakospermum, Ravenala (Traveller's Palm), Strelitzia (Bird-of-Paradise)

Taccaceae - Tacca Family
Tacca (Bat Plant)

Typhaceae - Cattail Family
Typha (Cattail)

Xanthorrhoeaceae - Grass Tree Family
Xanthorrhoea (Grass Tree)

Zingiberaceae - Ginger Family
Alpinia (Ginger Lily), Curcuma (Hidden Ginger), Globba, Hedychium (Butterfly Ginger), Kaempferia (Peacock Ginger), Zingiber (Ginger)




دیدگاه ها : نظرات
آخرین ویرایش: - -

Dicotyledonous Plant دولپه ایها

سه شنبه 30 خرداد 1391 11:14 ق.ظ

نویسنده : عسکر اله قلی
Selected Dicotyledonous Plant Orders & Their Families

Caryophyllales
Aizoaceae, Amaranthaceae, Basellaceae, Cactaceae, Caryophyllaceae, Chenopodiaceae, Didiereaceae, Molluginaceae, Nyctaginaceae, Phytolaccaceae, Portulacaceae

Magnoliales
Annonaceae, Calycanthaceae, Lauraceae, Magnoliaceae, Myristicaceae

Piperales
Piperaceae, Saururaceae

Aristolochiales
Aristolochiaceae

Nymphaeales
Nymphaeaceae

Ranunculales
Berberidaceae, Ranunculaceae

Papaverales
Papaveraceae

Hamamelidales
Hamamelidaceae, Platanaceae

Urticales
Cannabaceae, Moraceae, Ulmaceae, Urticaceae

Juglandales
Juglandaceae

Myricales
Myricaceae

Fagales
Betulaceae, Fagaceae

Polygonales
Polygonaceae

Plumbaginales
Plumbaginaceae

Dilleniales
Paeoniaceae

Theales
Actinidiaceae, Hypericaceae, Theaceae

Malvales
Bombacaceae, Malvaceae, Tiliaceae, Sterculiaceae

Violales
Begoniaceae, Bixaceae, Caricaceae, Cistaceae, Cochlospermaceae, Cucurbitaceae, Flacourtiaceae, Fouquieriaceae, Loasaceae, Passifloraceae, Tamaricaceae, Turneraceae, Violaceae

Salicales
Salicaceae

Capparales
Capparaceae, Brassicaceae

Ericales
Ericaceae

Ebenales
Ebenaceae, Sapotaceae, Styracaceae

Primulales
Primulaceae

Rosales
Crassulaceae, Fabaceae, Hydrangeaceae, Pittosporaceae, Rosaceae, Saxifragaceae

Haloragales
Haloragaceae

Myrtales
Combretaceae, Lythraceae, Melastomataceae, Myrtaceae, Onagraceae, Punicaceae

Proteales
Eleagnaceae, Proteaceae

Cornales
Cornaceae, Garryaceae

Celastrales
Aquifoliaceae, Celastraceae

Euphorbiales
Buxaceae, Euphorbiaceae

Rhamnales
Rhamnaceae, Vitaceae

Sapindales
Aceraceae, Anacardiaceae, Burseraceae, Hippocastanaceae, Meliaceae, Rutaceae, Sapindaceae, Simaroubaceae

Geraniales
Geraniaceae, Oxalidaceae

Polygalales
Malpighiaceae, Polygalaceae

Apiales
Apiaceae, Araliaceae

Gentianales
Apocynaceae, Asclepiadaceae, Gentianaceae, Loganiaceae

Polemoniales
Convolvulaceae, Cuscutaceae, Hydrophyllaceae, Polemoniaceae, Solanaceae

Lamiales
Boraginaceae, Lamiaceae, Verbenaceae

Plantaginales
Plantaginaceae

Scrophulariales
Acanthaceae, Bignoniaceae, Gesneriaceae, Martyniaceae, 0leaceae, Pedaliaceae, Scrophulariaceae

Campanulales
Campanulaceae, Goodeniaceae

Rubiales
Rubiaceae

Dipsacales
Caprifoliaceae, Dipsacaceae

Asterales
Asteraceae


Part 2
Selected Dicotyledonous Plant Families & Their Genera

Acanthaceae - Acanthus Family
Anisacanthus (Hummingbird Bush), Barleria (Phillipine Violet), Crossandra, Dicliptera, Dyschoriste (Snake Herb), Fittonia (Nerve Plant), Hypoestes (Polka Dot Plant), Justicia (Mexican Honeysuckle, Shrimp Plant), Megaskepasma (Brazilian Red-Cloak), Odontonema (Firespike), Pachystachys (Yellow Shrimp Plant), Peristrophe (Tilo-Pilo), Pseuderanthemum (Chocolate Plant), Ruellia (Mexican Petunia), Siphonoglossa (Tube-Tongue), Thunbergia (Sky Vine)

Aceraceae - Maple Family
Acer (Maple)

Actinidiaceae - Actinidia Family
Actinidia (Kiwi Fruit)

Aizoaceae - Mesembryanthemum Family
Aptenia (Baby Sun-Rose), Carpobrotus (Hottentot Fig), Delosperma (Hardy Ice-Plant), Faucaria (Tiger Jaws), Lithops (Living Stones), Pleiospilos (Split Rock)

Amaranthaceae - Amaranth Family
Alternanthera (Joseph's Coat), Amaranthus (Amaranth), Celosia (Cock's Comb), Froelichia (Cottonweed), Gomphrena (Batchelor Button)

Anacardiaceae - Cashew Family
Anacardium (Cashew), Cotinus (Smoke Tree), Mangifera (Mango), Pistacia (Pistache), Rhus (Poison Ivy, Sumac), Schinus (Pepper Tree, Pirul)

Annonaceae - Annona Family
Annona (Cherimoya, Custard Apple, Guanabana), Asimina (Pawpaw)

Apiaceae (Umbelliferae) - Celery Family
Aegopodium (Goutweed), Ammi (Bishop's Weed), Anethum (Dill), Apium (Celery), Carum (Caraway), Coriandrum (Cilantro, Coriander), Cuminum (Cumin), Daucus (Carrot), Eryngium (Eryngo), Foeniculum (Fennel), Hydrocotyle (Water Pennywort), Levisticum (Lovage), Pastinaca (Parsnip), Petroselinum (Parsley)

Apocynaceae - Dogbane Family
Adenium (Desert Rose), Allamanda, Amsonia (Bluestar), Carissa (Natal Plum), Catharanthus (Madagascar Periwinkle, Vinca), Mandevilla (Chilean Jasmine), Nerium (Oleander), Pachypodium (Madagascar Palm), Plumeria, Tabernaemontana (Indian Carnation), Thevetia (Yellow Oleander), Vinca

Aquifoliaceae - Holly Family
Ilex (Holly)

Araliaceae - Aralia Family
Aralia, Brassaia (Schefflera), X Fatshedera (Botanical Wonder), Fatsia, Hedera (Algerian Ivy, English Ivy), Panax (Ginseng), Schefflera (Umbrella Tree)

Aristolochiaceae - Birthwort Family
Aristolochia (Dutchman's-Pipe Vine), Asarum (Wild Ginger)

Asclepiadaceae - Milkweed Family
Asclepias (Milkweed), Calotropis (Bowstring Hemp), Caralluma, Ceropegia (Parachute Plant), Cryptostegia (Rubber Vine), Cynanchum, Echidnopsis, Edithcolea, Gonolobus, Hoodia, Hoya, Huernia, Sarcostemma, Stapelia (Carrion Flower), Stephanotis (Madagascar Jasmine)

Asteraceae (Compositae) - Aster Family
Achillea (Yarrow), Ageratum, Aphanostephus (Lazy Daisy), Arctotis, Artemisia (Wormwood), Aster, Baccharis, Baileya (Desert Marigold), Bellis (English Daisy), Berlandiera (Green-Eyes), Calendula, Calyptocarpus (Horse Herb), Centaurea (Basket Flower), Chrysanthemum (Ox-Eye Daisy), Cichorium (Chicory), Cirsium (Thistle), Coreopsis (Tickseed), Cosmos, Cynara (Artichoke), Dahlia, Dendranthema (Mum), Dimorphotheca (African Daisy), Dyssodia (Dahlberg Daisy), Echinacea (Cone-Flower), Encelia (Brittlebush), Engelmannia (Engelmann Daisy), Erigeron (Fleabane), Eupatorium (Boneset), Euryops (Shrub Daisy), Gaillardia (Indian Blanket), Gazania, Gerbera (Gerber Daisy), Gynura (Velvet Plant), Helichrysum (Strawflower), Helianthus (Sunflower), Lactuca (Lettuce), Leontopodium (Edelweiss), Liatris (Gayfeather), Machaeranthera (Tahoka Daisy), Matricaria (False Chamomile), Melampodium (Blackfoot Daisy), Palafoxia, Parthenium (Guayule), Pseudogynoxis (Flame vine), Ratibida (Mexican Hat), Rudbeckia (Black-Eyed Susan), Santolina, Senecio (Groundsel), Silphium (Compass Plant), Solidago (Goldenrod), Stevia, Tagetes (Marigold), Tanacetum (Tansy), Taraxacum (Dandelion), Tithonia (Mexican Sunflower), Verbesina (Crown-Beard), Vernonia (Ironweed), Viguiera (Golden-Eye), Wedelia, Zinnia

Basellaceae - Basella Family
Anredera (Madiera Vine), Basella (Malabar Spinach)

Begoniaceae - Begonia Family
Begonia

Berberidaceae - Barberry Family
Berberis (Agarita, Barberry), Epimedium, Mahonia (Grape Holly), Nandina, Podophyllum (Mayapple)

Betulaceae - Birch Family
Alnus (Alder), Betula (Birch), Carpinus (Hornbeam), Corylus (Filbert), Ostrya (Hop Hornbeam)

Bignoniaceae - Bignonia Family
Bignonia (Cross Vine), Campsis (Trumpetvine), Catalpa, Chilopsis (Desert Willow), Clytostoma (Lavender Trumpetvine), Incarvillea, Jacaranda, Pandorea (Bower Plant), Paulownia (Princess Tree), Pithecoctenium (Monkeycomb), Podranea (Pink Trumpetvine), Radermachera (China Doll), Tecoma (Esperanza), Tecomaria (Cape Honeysuckle)

Bixaceae - Bixa Family
Bixa (Achiote, Annatto)

Bombacaceae - Bombax Family
Adansonia (Baobab), Bombax (Red Silk-Cotton Tree), Ceiba (Kapok), Chorisia (Floss-Silk Tree), Durio (Durian), Pachira (Water Chestnut), Pseudobombax (Shaving-Brush Tree)

Boraginaceae - Borage Family
Borago (Borage), Cordia (Wild Olive), Ehretia (Anaqua), Heliotropium (Heliotrope), Lithospermum (Puccoon), Pulmonaria (Lungwort)

Brassicaceae (Cruciferae) - Mustard Family
Alyssum (Madwort), Armoracia (Horseradish), Aurinia (Alyssum), Brassica (Broccoli, Cabbage, Cauliflower, Kale, Mustard), Cardamine (Bitter Cress), Eruca (Rocket Salad, Arugula), Iberis (Candytuft), Lepidium (Peppergrass, Garden Cress), Lunaria (Money Plant), Matthiola (Stocks), Nasturtium (Watercress), Raphanus (Radish), Rorippa (Yellow Cress), Wasabia (Japanese Horseradish, Wasabi)

Burseraceae - Torchwood Family
Boswellia (Frankincense), Bursera (Gumbo-Limbo), Commiphora (Myrrh)

Buxaceae - Boxwood Family
Buxus (Boxwood), Pachysandra (Spurge), Simmondsia (Jojoba)

Cactaceae - Cactus Family
Acanthocereus, Aporocactus (Rattail Cactus), Ariocarpus (Living-Rock Cactus), Astrophytum (Bishop's-Cap Cactus), Aztekium, Backebergia (Teddy Bear Cactus), Borzicactus (Old Man-of-the-Mountain), Carnegiea (Saguaro), Cephalocereus (Old Man Cactus), Cereus, Cleistocactus (Scarlet Bugler), Copiapoa, Coryphantha, Digitostigma, Echinocactus (Horse Crippler, Barrel Cactus), Echinocereus (Pitaya), Echinofossulocactus (Brain Cactus), Echinopsis (Sea-Urchin Cactus), Epiphyllum (Orchid Cactus), Epithelantha (Button Cactus), Espostoa (Peruvian Old Man Cactus), Ferocactus (Barrel Cactus), Geohintonia, Gymnocalycium (Chin Cactus), Haageocereus, Harrisia (Moon Cactus), Hylocereus (Queen-of-the-Night), Leuchtenbergia (Agave Cactus), Lobivia (Cob Cactus), Lophocereus (Senita), Lophophora (Peyote), Mammillaria (Nipple Cactus), Melocactus (Turk's-Cap Cactus), Myrtillocactus (Garambullo), Neobuxbaumia, Nopalea (Cochineal Plant), Notocactus (Ball Cactus), Nyctocereus (Night-Blooming Cereus), Obregonia, Opuntia (Cholla, Prickly Pear), Pachycereus (Giant Mexican Cereus), Pediocactus (Snowball Cactus), Peniocereus (Night-Blooming Cereus), Pereskia (Leaf Cactus), Pereskiopsis, Pilocereus, Quiabentia, Rebutia (Crown Cactus), Rhipsalidopsis (Easter Cactus), Rhipsalis (Mistletoe Cactus), Schlumbergera (Christmas Cactus), Selenicereus (Moon Cactus), Stenocereus (Organ-Pipe Cactus), Stetsonia (Toothpick Cactus), Thelocactus, Trichocereus, Turbinicarpus

Calycanthaceae - Calycanthus Family
Calycanthus (Sweet-Shrub)

Campanulaceae - Bellflower Family
Campanula (Bellflower, Harebell, Rampion)

Cannabaceae - Cannabis Family
Cannabis (Hemp), Humulus (Hops)

Capparaceae - Caper Family
Capparis (Caper), Cleome (Spider Flower), Polanisia

Caprifoliaceae - Honeysuckle Family
Abelia, Lonicera (Honeysuckle), Sambucus (Elderberry), Symphoricarpos (Coralberry), Viburnum

Caricaceae - Papaya Family
Carica (Papaya)

Caryophyllaceae - Carnation Family
Arenaria (Sand Wort), Dianthus (Pinks), Gypsophila (Baby's Breath), Lychnis (Rose Campion), Saponaria (Bouncing Bet), Silene (Catchfly)

Celastraceae - Bittersweet Family
Celastrus (Bittersweet), Euonymus, Maytenus (Mayten)

Chenopodiaceae - Spinach Family
Atriplex (Saltbush), Beta (Beet), Chenopodium (Epazote, Pigweed), Kochia (Burning Bush), Spinacia (Spinach)

Cistaceae - Rock Rose Family
Cistus (Rock Rose)

Cochlospermaceae - Cochlospermum Family
Amoreuxia (Yellow Show), Cochlospermum (Silk-Cotton Tree)

Combretaceae - Combretum Family
Bucida (Black Olive), Conocarpus (Buttonwood), Quisqualis (Rangoon Creeper), Terminalia (Myrobalan)

Convolvulaceae - Morning-Glory Family
Convolvulus (Bindweed), Cuscuta (Dodder), Dichondra, Evolvulus, Ipomoea (Morning-Glory, Sweet Potato)

Cornaceae - Dogwood Family
Aucuba, Cornus (Dogwood)

Crassulaceae - Crassula Family
Aeonium, Crassula (Jade Plant), Echeveria, Graptopetalum (Ghost Plant), Kalanchoe, Sedum, Sempervivum (Hens-and-Chicks)

Cucurbitaceae - Gourd Family
Citrullus (Watermelon), Cucumis (Cucumber, Kiwano), Cucurbita (Pumpkin, Squash), Ibervillea (Wild Balsam), Lagenaria (Gourd), Luffa (Dishcloth Gourd), Momordica (Bitter Gourd), Sechium (Chayote), Seyrigia, Xerosicyos

Didiereaceae - Didieria Family
Alluaudia, Alluaudiopsis, Decaryia, Didieria

Dipsacaceae - Teasel Family
Dipsacus (Teasel), Knautia, Scabiosa (Pincushion Flower, Scabious)

Ebenaceae - Ebony Family
Diospyros (Persimmon)

Eleagnaceae - Russian Olive Family
Eleagnus (Russian Olive, Silverberry)

Ericaceae - Heath Family
Arbutus (Madrone), Calluna (Heather), Erica (Heath), Rhododendron (Azalea), Vaccinium (Blueberry)

Euphorbiaceae - Spurge Family
Acalypha (Chenille Plant, Copper Plant), Breynia (Snowbush), Cnidoscolus (Chaya), Codiaeum (Croton), Croton (Dove Weed), Euphorbia (Poinsettia, Spruge), Hevea (Rubber), Jatropha (Leather-Stem), Manihot (Manioc), Monadenium, Pedilanthus (Redbird Plant), Ricinus (Castor Bean), Sapium (Chinese Tallow)

Fabaceae (Leguminosae) - Legume Family
Acacia, Amorpha (Lead Plant), Albizia (Mimosa), Arachis (Peanut), Baptisia (False Indigo), Bauhinia (Orchid Tree), Caesalpinia (Pride-of-Barbados), Calliandra (Fairy Duster), Cassia (Senna), Ceratonia (Carob), Cercis (Redbud), Cicer (Garbanzo), Clianthus (Desert Pea), Clitoria (Butterfly Pea), Dalea, Delonix (Royal Poinciana), Dolichos (Hyacinth Bean), Erythrina (Coral Bean), Eysenhardtia (Kidneywood), Gleditsia (Honeylocust), Glycine (Soybean), Gymnocladus (Kentucky Coffee Tree), Indigofera (Indigo), Lathyrus (Sweet Pea), Lens (Lentil), Leucaena (Lead Tree), Lupinus (Bluebonnet, Lupine), Medicago (Alfalfa), Mimosa (Cat's-Claw), Myrospermum (Sweetwood), Oxytropis (Locoweed), Pachyrhizus (Jicama), Parkinsonia (Retama), Phaseolus (Bean), Pisum (Pea), Pithecellobium (Texas Ebony), Prosopis (Mesquite), Psophocarpus (Winged Bean), Psoralea (Indian Turnip), Pueraria (Kudzu), Robinia (Locust), Schrankia (Sensitive Briar), Sesbania (Rattlebox), Sophora (Texas Mountain Laurel), Spartium (Broom), Tamarindus (Tamarind), Trifolium (Clover), Vicia (Vetch), Vigna (Snail Vine), Wisteria

Fagaceaae - Beech Family
Castanea (Chestnut), Fagus (Beech), Lithocarpus (Tanbark Oak), Quercus (Oak)

Flacourtiaceae - Flacourtia Family
Hydnocarpus (Chaulmdogra-Oil Tree), Xylosma

Fouquieriaceae - Ocotillo Family
Fouquieria (Boojum Tree, Ocotillo)

Garryaceae - Garrya Family
Garrya (Silk-Tassel)

Gentianaceae - Gentian Family
Centaurium (Mountain Pink), Eustoma (Prairie Bluebell), Exacum (Persian Violet)

Geraniaceae - Geranium Family
Erodium (Storksbill), Geranium (Cranesbill), Pelargonium (Geranium), Sarcocaulon

Gesneriaceae - Gesneriad Family
Achimenes, Aeschynanthus (Lipstick Plant), Columnea, Episcia (Flame Violet), Gloxinia, Nautilocalyx, Nematanthus, Saintpaulia (African Violet), Sinningia (Gloxinia), Streptocarpus (Cape Primrose)

Goodeniaceae - Goodenia Family
Scaevola

Haloragaceae - Water Milfoil Family
Myriophyllum (Parrot's Feather), Proserpinaca

Hamamelidaceae - Witch Hazel Family
Hamamelis (Witch Hazel), Liquidambar (Sweetgum), Loropetalum

Hippocastanaceae - Horse Chestnut Family
Aesculus (Buckeye)

Hydrangeaceae - Hydrangea Family
Decumaria (Climbing Hydrangea), Deinanthe, Deutzia, Fendlera, Hydrangea, Jamesia, Kirengeshoma, Philadelphus (Mockorange), Platycrater

Hydrophyllaceae - Waterleaf Family
Phacelia

Hypericaceae - Hypericum Family
Hypericum (St. John's Wort)

Juglandaceae - Walnut Family
Carya (Hickory, Pecan), Juglans (Walnut)

Lamiaceae (Labiatae) - Mint Family
Agastache (Anise Hyssop), Ajuga, Coleus (Cuban Oregano), Hedeoma (Mock Pennyroyal), Hyptis, Hyssopus (Hyssop), Lamium (Dead Nettle), Lavandula (Lavender), Leonotis (Lion's-Ear), Marrubium (Horehound), Mentha (Mint), Monarda (Beebalm), Nepeta (Catmint), Ocimum (Basil), Origanum (Oregano), Orthosiphon (Cat's Whiskers), Perilla, Perovskia (Russian Sage), Phlomis (Jerusalem Sage), Physostegia (Obedient Plant), Plectranthus (Swedish Ivy), Poliomintha (Mexican Oregano), Rosmarinus (Rosemary), Salvia (Sage), Satureja (Savory), Scutellaria (Skullcap), Solenostemon (Coleus), Stachys (Lamb's Ears), Teucrium (Germander), Thymus (Thyme)

Lauraceae - Laurel Family
Cinnamomum (Camphor, Cinnamon), Laurus (Laurel), Lindera (Spicebush), Litsea (Pond-Spice), Persea (Avocado), Sassafras

Loasaceae - Loasa Family
Eucnide (Yellow Rock-Nettle)

Lobeliaceae - Lobelia Family
Lobelia

Loganiaceae - Logania Family
Buddleia (Butterfly Bush), Gelsemium (Carolina Jessamine), Spigelia (Indian Pink)

Lythraceae - Loosestrife Family
Cuphea (Mexican Heather), Heimia, Lagerstroemia (Crepe Myrtle), Lawsonia (Henna, Resedad), Lythrum (Loosestrife)

Magnoliaceae - Magnolia Family
Liriodendron (Tulip Poplar), Magnolia, Michelia (Banana Shrub)

Malpighiaceae - Malpighia Family
Galphimia (Thryallis), Malpighia (Barbados Cherry), Mascagnia (Butterfly Vine)

Malvaceae - Mallow Family
Abelmoschus (Okra), Abutilon (Flowering Maple), Alcea (Hollyhock), Callirhoe (Winecup), Gossypium (Cotton), Hibiscus, Kosteletzkya (Salt-Marsh Mallow), Lavatera (Tree Mallow), Malva (Hollyhock), Malvaviscus (Turk's-Cap), Pavonia (Rock Mallow), Sida (Dollar Weed), Sphaeralcea (Globe Mallow), Wissadula

Martyniaceae - Martynia Family
Ibicella, Martynia, Proboscidea (Unicorn Plant)

Melastomataceae - Melastoma Family
Centradenia, Medinilla (Malaysian Orchid Tree), Tibouchina (Princess Flower)

Meliaceae - Mahogany Family
Azadirachta (Neem Tree), Melia (Chinaberry), Swietenia (Mahogany)

Molluginaceae - Mollugo Family
Mollugo (Velcro Weed)

Moraceae - Mulberry Family
Broussonetia (Paper Mulberry), Cecropia (Ant Plant), Dorstenia, Ficus (Fig), Maclura (Bois D'Arc), Morus (Mulberry)

Myricaceae - Bayberry Family
Myrica (Bayberry, Wax Myrtle)

Myristicaceae - Nutmeg Family
Myristica (Mace, Nutmeg)

Myrsinaceae - Myrsine Family
Ardisia

Myrtaceae - Myrtle Family
Callistemon (Bottlebrush), Eucalyptus, Eugenia (Surinam Cherry), Feijoa (Pineapple Guava), Myrtus (Myrtle), Pimenta (Allspice), Psidium (Guava), Syzygium (Clove, Brush Cherry)

Nyctagoinaceae - Four O'Clock Family
Abronia (Sand Verbena), Bougainvillea, Mirabilis (Four O'Clock), Nyctaginia (Devil's Bouquet)

Nymphaeaceae - Waterlily Family
Cabomba (Fan Wort), Nelumbo (Lotus), Nuphar (Yellow Waterlily), Nymphaea (Waterlily), V ictoria (Giant Waterlily)

Oleaceae - Olive Family
Chionanthus (Fringe Tree), Forestiera (Elbow Bush), Forsythia, Fraxinus (Ash), Jasminum (Jasmine), Ligustrum, Menodora, Olea (Olive), Osmanthus (Sweet Olive), Syringa ( Lilac)

Onagraceae - Evening Primrose Family
Clarkia (Farewell-to-Spring), Fuchsia, Gaura, Oenothera (Evening Primrose)

Oxalidaceae - Oxalis Family
Averrhoa (Carambola, Star Fruit), Oxalis

Paeoniaceae - Peony Family
Paeonia (Peony)

Papaveraceae - Poppy Family
Argemone (Prickly Poppy), Bocconia, Eschscholzia (California Poppy), Hunnemannia (Mexican Tulip-Poppy), Papaver (Poppy)

Passifloraceae - Passion Flower Family
Adenia, Passiflora (Passion Flower)

Pedaliaceae - Pedalium Family
Sesamum (Sesame)

Phytolaccaceae - Pokeweed Family
Phytolacca (Pokeweed), Rivina (Rouge Plant)

Piperaceae - Pepper Family
Peperomia, Piper (Hoja Santa, Pepper)

Pittosporaceae - Pittosporum Family
Pittosporum

Plantaginaceae - Plantain Family
Plantago (Plantain, Psyllium)

Platanaceae - Sycamore Family
Platanus (Sycamore)

Plumbaginaceae - Plumbago Family
Ceratostigma (Chinese Plumbago), Plumbago

Polemoniaceae - Phlox Family
Gilia (Bird's-Eyes), Ipomopsis (Standing Cypress), Phlox

Polygalaceae - Milk Wort Family
Polygala (Milk Wort), Securidaca (Flor de Mole)

Polygonaceae - Buckwheat Family
Antigonon (Coral Vine, Queen's Wreath), Coccoloba (Sea Grape), Eriogonum (Buckwheat), Homalocladium (Centipede Plant), Muehlenbeckia (Wire Plant), Polygonum (Knotweed), Rheum (Rhubarb), Rumex (Dock, Sorrel)

Portulacaceae - Purslane Family
Anacampseros, Lewisia, Portulaca (Purslane), Portulacaria (Elephant Bush), Talinum (Jewels-of-Opar)

Primulaceae - Primrose Family
Cyclamen, Dodecatheon (Shooting Star), Lysimachia (Moneywort), Primula (Primrose)

Proteaceae - Protea Family
Banksia, Grevillea (Silk Oak), Macadamia, Protea

Punicaceae - Pomegranate Family
Punica (Pomegranate)

Ranunculaceae - Buttercup Family
Aconitum (Aconite), Anemone, Aquilegia (Columbine), Caltha (Marsh Marigold), Cimicifuga (Bugbane, Cohosh), Clematis, Consolida (Annual Larkspur), Delphinium, Nigella (Love-in-a-Mist), Ranunculus (Buttercup)

Rhamnaceae - Buckthorn Family
Berchemia (Supplejack), Ceanothus (California Lilac, New Jersey Tea), Colubrina (Snakewood), Rhamnus (Buckthorn), Zizyphus (Jujube)

Rosaceae - Rose Family
Amelanchier (Serviceberry), Cercocarpus (Mountain Mahogany), Chaenomeles (Flowering Quince), Cotoneaster, Cowania (Cliff Rose), Crataegus (Hawthorn), Cydonia (Quince), Duchesnea (Mock Strawberry), Eriobotrya (Loquat), Fallugia (Apache Plume), Fragaria (Strawberry), Kerria, Malus (Apple), Mespilus (Medlar), Photinia, Potentilla (Cinquefoil), Poterium (Burnet), Prunus (Almond, Cherry, Peach, Plum), Pyracantha, Pyrus (Pear), Raphiolepis (India Hawthorn), Rosa (Rose), Rubus (Bramble), Spiraea

Rubiaceae - Madder Family
Adina (Chinese Buttonbush), Asperula (Woodruff), Bouvardia, Cephalanthus (Buttonbush), Cinchona (Quinine), Coffea (Coffee), Gardenia, Hamelia (Firebush), Ixora, Pentas, Serissa

Rutaceae - Rue Family
Amyris, Casimiroa (White Zapote), Choisya (Mexican Orange), X Citrofortunella (Calamondin, Yuzuquat), Citrus (Grapefruit, Lemon, Lime, Mandarin, Orange, Tangerine), Dictamnus (Gas Plant), Eremocitrus, Esenbeckia, Evodia, Fortunella (Kumquat), Poncirus (Trifoliate Orange), Ptelea (Hop Tree), Ruta (Rue), Severinia (Box Orange), Zanthoxylum (Toothache Tree)

Salicaceae - Willow Family
Populus (Cottonwood, Poplar), Salix (Willow)

Sapindaceae - Soapberry Family
Cardiospermum (Balloon Vine), Dodonaea, Koelreuteria (Golden-Rain Tree), Litchi (Lychee), Sapindus (Soapberry), Ungnadia (Mexican Buckeye), Xanthoceras

Sapotaceae - Sapodilla Family
Bumelia, Manilkara (Chicle)

Saururaceae - Lizard's Tail Family
Houttuynia (Chameleon Plant)

Saxifragaceae - Saxifrage Family
Bergenia, Heuchera (Coralbells), Itea (Sweet-Spire), Ribes (Currant)

Scrophulariaceae - Fig Wort Family
Agalinis (Gerardia), Angelonia, Antirrhinum (Snapdragon), Asarina, Bacopa (Water Hyssop), Calceolaria (Pocketbook Flower), Castilleja (Indian Paintbrush), Digitalis, Leucophyllum (Cenizo, Texas Sage), Penstemon, Russelia (Firecracker Bush), Torenia (Wishbone Plant), Verbascum (Mullein), Veronica

Simaroubaceae - Quassia Family
Ailanthus (Tree-of-Heaven)

Solanaceae - Nightshade Family
Atropa (Belladonna), Browallia (Bush Violet), Brugmansia (Angel's Trumpet), Brunfelsia (Yesterday, Today & Tomorrow), Capsicum (Pepper), Cestrum (Night-Blooming Jessamine), Cyphomandra (Tamarillo, Tree Tomato), Datura (Jimson Weed), Lycium (Wolfberry), Lycopersicon (Tomato), Mandragora (Mandrake), Nicotiana (Tobacco), Nierembergia (Cupflower), Petunia, Physalis (Tomatillo), Solandra (Cup-of-Gold), Solanum (Eggplant, Naranjilla, Potato, Potato Vine), Withania (Ashwagandha)

Sterculeaceae - Sterculia Family
Brachychiton (Bottle Tree), Cola (Cola Nut), Firmiana (Parasol Tree, Varnish Tree), Theobroma (Chocolate)

Styracaceae - Snowbell Family
Halesia (Silverbell), Styrax (Snowbell)

Tamaricaceae - Salt Cedar Family
Tamarix (Salt-Cedar)

Theaceae - Tea Family
Camellia (Camellia, Tea), Cleyera

Tiliaceae - Linden Family
Corchorus (Jute), Tilia (Basswood, Linden)

Turneraceae - Turnera Family
Turnera

Ulmaceae - Elm Family
Celtis (Hackberry), Ulmus (Elm)

Urticaceae - Nettle Family
Boehmeria (Ramie), Pilea (Artillery Plant, Creeping Charlie), Urtica (Nettle)

Verbenaceae - Verbena Family
Aloysia (Beebrush), Callicarpa (Beautyberry), Caryopteris (Bluemist), Citharexylum (Fiddlewood), Clerodendrum (Glory-Bower, Mexican Hydrangea), Duranta, Lantana, Lippia (Red Brush), Phyla (Frogfruit), Stachytarpheta (Porterweed), Tectona (Teak), Verbena, Vitex (Chaste Tree)

Violaceae - Violet Family
Viola (Pansy, Violet)

Vitaceae - Grape Family
Ampelopsis (Pepper Vine), Cissus (Grape Ivy), Cyphostemma, Parthenocissus (Virginia Creeper), Vitis (Grape)

Zygophyllaceae - Caltrop Family
Guaiacum (Lignum Vitae), Larrea (Creosote Bush)




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INTRODUCTION TO TAXONOMY

سه شنبه 30 خرداد 1391 11:03 ق.ظ

نویسنده : عسکر اله قلی



Castilleja miniata, photo by Werner Eigelssreiter

What is Taxonomy and Where Did it Originate?

by

Jamie Fenneman

Taxonomy is the method by which scientists, conservationists, and naturalists classify and organize the vast diversity of living things on this planet in an effort to understand the evolutionary relationships between them. Modern taxonomy originated in the mid-1700s when Swedish-born Carolus Linnaeus (also known as Carl Linnaeus or Carl von Linné) published his multi-volume Systema naturae, outlining his new and revolutionary method for classifying and, especially, naming living organisms. Prior to Linnaeus, all described species were given long, complex names that provided much more information than was needed and were clumsy to use. Linnaeus took a different approach: he reduced every single described species to a two-part, Latinized name known as the “binomial” name. Thus, through the Linnaean system a species such as the dog rose changed from long, unwieldy names such as Rosa sylvestris inodora seu canina and Rosa sylvestra alba cum rubore, folio glabro to the shorter, easier to use Rosa canina. This facilitated the naming of species that, with the massive influx of new specimens from newly explored regions of Africa, Asia, and the Americas, was in need of a more efficient and usable system.

Although trained in the field of medicine, botany and classification were the true passions of Linnaeus and he actively explored northern Europe and described and named hundreds of new plant species during his lifetime. As well, Linnaeus spent a great deal of time describing and naming new plant specimens that were sent to him from around the world by other botanists, including from the newly explored regions of the New World. Linnaeus classified this multitude of new plant species based upon their reproductive structures, a method which is still largely in use today. In fact, the majority of the species described by Linnaeus are still recognized today, indicating how far ahead of his time he truly was. Although somewhat rudimentary by today’s standards, Linnaeus’ methods of describing species in such a way as to represent the relationships between them changed the face of taxonomy and allowed biologists to better understand the complex natural world around us.


Carex aurea, photo by Adolf Ceska

How Do We Classify Plants?

Plants, and indeed all organisms, are classified in a hierarchical system that attempts to illustrate the evolutionary relationships between the various groupings within the hierarchy. This concept of relatedness forms the backbone of modern classification schemes. Scientists who attempt to classify organisms and place them within an evolutionary framework are called Taxonomists, the most famous of which would be Linnaeus himself. At the broadest level, all organisms on the planet are classified into 5 Kingdoms: Animalia (animals), Plantae (plants, some multicellular algae), Fungi (fungi), Monera (prokaryotic bacteria), and Protista (eukaryotic bacteria, most algae, etc.), representing the most ancient branches of the evolutionary “tree of life.” Organisms in any given Kingdom may be separated from organisms in any other Kingdom by many hundreds of millions, if not billions, of years of evolution. Historically, all organisms known were grouped into only two Kingdoms: organisms that had finite growth, moved, and ate were grouped into the Kingdom Animalia, while organisms that had indefinite growth, didn’t move, and didn’t eat were grouped into the Kingdom Plantae. Of course, as science progressed, it became increasingly evident that such a simplistic approach to taxonomy was ineffective and many species were found that did not fit either grouping particularly well. The proposal to move to an eight-Kingdom system suggests that our current classification system, with its five Kingdoms, may yet change again as our understanding of the diversity of organisms around us continues to grow.

Within each Kingdom, the organisms are grouped into several Phyla (sing. Phylum), also known as Divisions, which represent smaller groupings of more recognizable forms. Although the Kingdom Animalia contains a large number of Phyla (such as chordates [including vertebrates], echinoderms, annelids, arthropods, etc.), Kingdom Plantae contains only ten. The Phylum Bryophyta (mosses, liverworts, hornworts), the most primitive of all true plants, differs from other plant Phyla in that it is non-vascular, meaning that it lacks water-conducting tissues which bring water from the roots of the plant up into the crown, and that the gametophyte (vegetative) generation predominates over the sporophyte (reproductive) generation. The Phyla Psilophyta (whisk ferns), Lycopodiophyta (club-mosses, spike-mosses, quillworts), Equisetophyta (horsetails), and Polypodiophyta (true ferns), including all vascular plants that reproduce using spores, also form an ancient, though largely artificial, grouping and are often referred to as Pteridophytes. The Phyla Cycadophyta (cycads), Ginkgophyta (ginkgo), Gnetophyta (vessel-bearing gymnosperms), and Coniferophyta (conifers) form a second primitive grouping of vascular plants, known as Gymnosperms, which are characterized by the presence of naked seeds (the literal translation of “gymno-sperm”). The final Phylum, Magnoliophyta, contains all of the vascular, flowering plants that are considered to be the most advanced and recently-evolved plants occurring on the planet today.


Brodiaea coronaria, photo by Dave Ingram

Within each Phylum, the organisms involved are grouped into progressively smaller, more refined groupings of similar individuals. Below Phylum, organisms are grouped into Classes, Orders, and Families, the latter being the largest-order taxonomic grouping that is commonly used by amateur botanists. As an example, the Phylum Magnoliophyta is split into 2 well-known Classes: Magnoliopsida (Dicotyledons) and Liliopsida (Monocotyledons) based on a variety of features from leaf venation and flower structure to growth form, root structure, and seed structure, each class with its subsequent Orders and Families. Each family is further divided into Genera (sing. Genus) representing organisms with similar morphology, structure, reproductive organs, and, perhaps most importantly, evolutionary history. These genera represent groupings that many of us are most familiar with, such as Rhododendron, Rosa, Chrysanthemum, etc. and are designed to illustrate that the individual organisms grouped within the same genus are very closely related to each other. In fact, the genus is the taxonomic grouping that represents the closest relationship between organisms which, at the smallest taxonomic level, are called Species. Each individual species is given a specific name that, when combined with the generic name, produces the two-term “binomial” naming system that Linnaeus pioneered. For example, within the genus Rosa are a variety of species such as acicularis, nutkatensis, and woodsii. Through the binomial naming system, these species become Rosa acicularis, R. nutkatensis and R.woodsii (the generic name is shortened to the first initial when listing several species in the same genus).


Erythronium oreganum, photo by Rod Innes

Of course, as with many scientific theories or strategies, there are problems with this system in the way it is currently applied and as a result it is in a continual state of flux, especially at the lower levels of the hierarchy. Even at the highest level (Kingdom), several groups are still cause for debate among taxonomists as to their placement. For example, how do we classify lichens? Lichens were originally placed within the Kingdom Plantae until further research showed that what we call “lichens” are actually a symbiotic relationship between certain species of fungi and certain species of algae. The two species, which can often survive independent of each other, combine to form a third plant-like “species” of organism called “lichen” that differs greatly from either of its two parent species yet functions as its own reproductive, evolutionary organism (thus meeting the criteria for a “species”). Currently lichens are included within the Kingdom Fungi since the fungal partner is the driving force behind the union (essentially “cultivating” its algal partner in order to produce its own nourishment) but this treatment still does not really fit with traditional taxonomy.

Another example of how nature continually confounds attempts to classify it is the vast array of plant-like organisms grouped under the term “algae.” The confusion results from the fact that most algae are unicellular or, if multicellular, composed of a single or very few cell types amassed together to function as a larger individual. So, do we classify multicellular algae based on the characteristics of the single cell (Protista) or as an independent multicellular organism (Plantae)? Most algae are currently placed within the Kingdom Protista despite their often plant-like appearance, with only a few of the multi-cellular forms remaining within the Kingdom Plantae. This treatment is not followed by all authors, however, as some retain all of the algae as a subkingdom within the Kingdom Plantae. Regardless of the treatment, it is obvious that the great diversity within the group “algae,” as well as its unusual morphological and cellular characteristics, is a hindrance to botanists who attempt to classify them within our current taxonomic systems.


Sedum spathulifoliium, photo by Kevin Newell

What is a “Species”?

At the lowest level of the classification hierarchy is the “species”, a human-derived concept that, to this day, is still not completely understood by scientists. The general consensus in past decades has been that a “species” is a group of similar individuals which can reproduce successfully with each other while at the same time being reproductively isolated from other similar species (known as the “Biological Species Concept”). This interpretation worked reasonably well when it was first proposed, but the more we learn about ecological systems the more apparent it becomes that nature is by no means so simple. The evolutionary process is a continuum whereby a portion of the population of one entity gradually becomes more and more distinctive and discrete, eventually reaching a state in which it is reproductively isolated from its parent “species.” The infinite range of variation between the two ends of this evolutionary process means that many populations are difficult to assign to either a parent species or a new, independent species.

A newer species concept, known as the “Phylogenetic Species Concept”, attempts to give specific status to any identifiable populations that have a unique evolutionary history and differ collectively in some characteristics from other populations. This system, which places more weight on the evolutionary process and genetic differences between populations, naturally results in a far greater number of recognizable species than the more conservative Biological Species Concept. In truth, however, neither of these widely accepted concepts appears to fully represent the extraordinary complexities of the natural world, and perhaps the most effective current method of species classification is a combination of both systems.


<Ranunculus californicus and Plectritis congesta, photo by Adolf Ceska

Subspecific Taxonomy

Another method used by taxonomists to deal with the variation within species is the use of “infraspecific” or “subspecific” taxonomy. Many species are not uniform in appearance throughout their distribution, and by assigning subspecies and varietal names to the identifiable populations scientists are able to catalogue and name this variation.

Populations that are approaching species status are typically categorized as subspecies (often written as “ssp.” or “subsp.”), especially when these forms have discrete geographic distributions. For example, in the species Salix reticulata (net-leaved willow) individuals occurring throughout the mountain ranges of the interior of the province with hairy capsules and a strong net-like pattern of venation on the leaves are named S. reticulata ssp.reticulata, while the populations on the Queen Charlotte Islands that have hairless capsules and a weaker net-like venation pattern on the leaves are known as S. reticulata ssp.glabellicarpa. These two subspecies have different geographic ranges and represent evolutionary lines that are fairly well defined, but are similar enough to be classed within the same species.




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عید مبعث بر همگان مبارک

دوشنبه 29 خرداد 1391 10:34 ق.ظ

نویسنده : عسکر اله قلی



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Aloe vera

سه شنبه 23 خرداد 1391 12:34 ب.ظ

نویسنده : عسکر اله قلی

Classification for Kingdom Plantae Down to Species Aloe vera (L.) Burm. f.

Click on names to expand them, and on P for PLANTS profiles.

 
Up to the Kingdom
Kingdom  Plantae – Plants
Subkingdom  Tracheobionta – Vascular plants
Superdivision  Spermatophyta – Seed plants
Division  Magnoliophyta – Flowering plants
Class  Liliopsida – Monocotyledons
Subclass  Liliidae
Order  Liliales
Family  Aloaceae – Aloe family
Genus  Aloe L. – aloe P
Species  Aloe vera (L.) Burm. f. – Barbados aloe



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پوست ماگنولیا بوی دهان را مطبوع می کند

پنجشنبه 18 خرداد 1391 11:47 ق.ظ

نویسنده : عسکر اله قلی
درخت ماگنولیا
درخت ماگنولیا تنها باغ ها را زیبا نمی کند
پژوهشگران آمریکایی دریافته اند که پوست درخت ماگنولیا می تواند بسیار موثرتر از خود نعناع به تنهایی، بوی بد دهان را از بین ببرد.

این ماده که هم اکنون برای درمان چندین ناراحتی مختلف بکار برده می شود، همچنین ممکن است در مبارزه با یک نوع باکتری که باعث پوسیدگی دندان می شود نیز موثر باشد.

پژوهشگران موسسه ریگلی (Wrigley) این مسئله را با آزمایش بر روی نه داوطلب دریافتند.

این پژوهشگران در مقاله ای در نشریه "شیمی غذا و کشاورزی" عنوان کردند که نعناع آغشته به ماگنولیا 20 برابر بیشتر از نعناع به تنهایی، باکتری های مسبب بوی بد دهان و پوسیدگی دندان ها را از بین می برد.

پس از یک ساعت نعناع آغشته به ماگنولیا بیش از 60 درصد باکتری های مضر را از بین برده بود اما نعناع به تنهایی در همین مدت کمتر از 4 درصد باکتری ها را از بین برد.

همه داوطلبان افرادی سالم بودند که آزمایش ها درست پس از صرف نهار بر روی آنها انجام شده بود.

در این مقاله از بوی بد دهان بعنوان یک مشکل عمده اجتماعی و روانی نام برده شده است و در آن آمده : "پوست درخت ماگنولیا در آزمایشات اثر یک ضد باکتری قوی از خود نشان داد و می توان به منظور تازه کردن بوی دهان، از آن در ساخت قرص های نعناع یا آدامس استفاده کرد."

طرفداران استفاده از ماگنولیا همیشه از این گیاه بعنوان ماده ای یاد می کنند که آثار و عوارض بیماری های مختلفی، از رماتیسم گرفته تا آسم را کاهش می دهد.

دکتر نایجل کارتر، از مدیران "بنیاد سلامت دندان بریتانیا" نتایج این پژوهش را بسیار امیدوار کننده خواند.

"قرص نعناع معمولی تنها بطور موقت بوی بد دهان را می پوشاند و هرچند آدامس هم در تقویت جریان آب دهان موثر است، اما این پژوهش می تواند در ایجاد روش های صحیح مراعات بهداشت دهان گام دیگری به جلو محسوب شود."

با این وجود آقای کارتر تاکید کرد که این پیشرفت به هیچ وجه از اهمیت و لزوم دوبار مسواک زدن در روز کم نمی کند.




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دانشمندان روسی موفق شده اند با استفاده از دانه ها و میوه ذخیره شده در انبار آذوقه یک سنجاب سیبریایی نوعی گیاه ۳۰۰۰۰ ساله را احیا کنند.

به نوشته روزنامه انگلیسی «گاردین»، گروهی از دانشمندان روسی توانسته اند تنها با استفاده از باقی مانده بافت میوه، یک گیاه کامل را که هزاران سال منقرض شده بود و بر روی کره زمین وجود خارجی نداشت، باری دیگر به چرخه حیات بازگردانند. گامی پیشروانه که می تواند راه را برای زنده کردن انواع دیگر جانداران هموار کند.

گیاه زنده شده «قلیانک برگ‌باریک» نام دارد که نام علمی آن «Silene stenophylla» است و قدیمی ترین گونه گیاهی است که تا کنون بازسازی شده و توانایی ازدیاد و تولید گل های سفیدرنگ و دانه های قابل رشد را نیز داراست.

آزمایش اخیر نشان می دهد که لایه یخ‌های دائمی اعماق زمین، مانند یک محفظه طبیعی برای اَشکال مختلف حیات عمل می کند.

دانشمندان اعلام کرده اند که با در نظر گرفتن یافته های پژوهش جدید، به دنبال یافتن خزانه ژنی کهن مربوط به دوران پیش از به وجود آمدن زندگی بر روی زمین هستند که، از دیدگاه نظری، زمان زیادی از نا پدید شدنش می گذرد.

پیش تر، دانشمندان کانادایی توانسته بودند گیاهانی با قدمت بسیار کمتر را از دانه های یافته شده در انبار آذوقه برجای مانده از حیوانات بازسازی کنند.

سوِتلانا یاشینا از مؤسسه زیست‌فیزیک سلولی آکادمی علوم روسیه، که رهبری پروژه احیای گیاه دوران ماقبل عصر یخبندان را بر عهده داشته، می گوید گیاه بازسازی شده شباهت بسیاری به نمونه جدیدش دارد که هنوز هم در برخی مناطق شمال شرقی سیبری می روید. این دانشمند روس می افزاید امیدوار است که گروه تحت رهبری او بتوانند نمونه های منقزض شده بیشتری را در آینده نزدیک احیا کنند.

استانیسلاو گوبین، یکی از اعضای تیم در گزارشی درباره آزمایش فوق می نویسد: «سنجاب ها برای ساخت انبارهای آذوقه، به اندازه یک توپ فوتبال، زمین یخ زده را سوراخ می کردند، اول یونجه و سپس موی حیوانات را در کف حفره ایجاده شده جمع می کردند و به این ترتیب یک مخزن یخی طبیعی می ساختند.»

انبار های کشف شده در عمق ۱۲۵ پایی (۳۸ متری) زیر سطح کنونی زمین قرار داشتند و علاوه بر دانه، لایه هایی از استخوان پستانداران بزرگ مانند ماموت، کرگدن پشمالو، گاومیش کوهاندار، اسب و گوزن را در خود جای داده بودند. استانیسلاو گوبین با اشاره به این مواد می گوید: «اگر شانس بیاوریم، می توانیم بافت منجمد شده بدن سنجاب ها را نیز بیابیم و در آن صورت راه را برای احیای احتمالی پستانداران عصر یخبندان هموار کنیم.»

در همین حال دانشمندان ژاپنی نیز در حال جست و جوی محل برای یافتن بقایای ماموت های کهنسال هستند، اما گوبین  امیدوار است که روس ها زودتر بتوانند بافت یخ زده حیوانات را برای احیا به دست آورند، وی می گوید: «اینجا سرزمین ماست و خودمان تلاش می کنیم که زودتر از بقیه پیدایشان کنیم.»



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گروهی از پژوهشگران بریتانیایی که در حال تحقیق در دهانه آتشفشانی در عمق حدود دو و نیم کیلومتری کف اقیانوس هند بودند، موفق شدند تصاویر جالبی از حیات در یکی از نقاط غیر قابل سکونت اقیانوس هند ارائه دهند.

این تیم تحقیقاتی توانسته به مجموعه ای از موجودات زنده که توانایی زندگی در آبهای بسیار گرم را دارند، دست یابد.

از جمله این جانوران، نوعی خرچنگ "مو دار" ،حلزون دریایی فلس دار و خیار دریایی است و پژوهشگران در نظر دارند با مطالعه آنها، چگونگی تکامل این موجودات را تشخیص دهند.

به گفته این پژوهشگران بعضی از این موجودات در دنیای علم تازگی دارند.

این دهانه های آتشفشان بستر دریا، اولین بار در سال ۱۹۷۷ میلادی کشف شدند. این گونه دهانه ها باعث می شوند تا آب های بسیار گرم غنی از مواد معدنی به خارج راه پیدا کنند.

این گروه تحقیقاتی از دانشگاه ساوتهمپتون بخصوص به دهانه های آتشفشان بستر دریا در گسل اقیانوس هند جنوبی علاقه نشان دادند.

این منطقه به این دلیل که گسل ها در آن به کندی گسترش می یابد، منطقه ای غیر عادی بشمار می رود. این ویژگی به معنای آن است که فعالیت های آتشفشانی در این گسل ها در مقایسه با سایر گسل ها کندتر است.

پروفسور جان کاپلی، سرپرست این تیم تحقیقاتی، گفته است این مکان، از نظر وجود موجوداتی که در دهانه آتشفشان زیست می کنند، محلی منحصر به فرد است.

این تیم تحقیقاتی با روباتی موسوم به (Kiel ۶۰۰۰ ) توانست از راه دور اطراف دهانه این آتشفشان را مطالعه کند.

در داغ ترین منطقه اطراف این دهانه آتشفشان، پژوهشگران موفق به کشف مار، میگو، صدف دریایی، خیار و خرچنگ شدند.

موجوداتی نظیر این خیار دریایی در سایر گسل های بستر دریا یافت نشده است

آنگاه این پژوهشگران این موجودات را با جانداران دیگری که در دهانه های آتشفشان بستر سایر گسل ها کشف شده، مقایسه کردند.

پروفسور کاپلی گفته است:" ما انتظار داشتیم که به شباهتهایی بین آنچه در دهانه های آتشفشان اقیانوس اطلس دیدیم با آنچه در دهانه آتشفشان اقیانوس هند مشاهده کنیم، دست پیدا کنیم. اما در گسل اقیانوس هند جنوبی به موجوداتی برخورد کردیم که پیش از این مشابه آن را در گسل های دیگر ندیده بودیم و این شگفتی بزرگی برای ما بود. "

پروفسور کاپلی می افزاید ارتباط این محل با سایر نقاط جهان محققان را بسیار هیجانزده کرده است.

این تیم تحقیقاتی همچنین از تنوع حیات در این محل شگفت زده شده است.

گفته می شود این یافته ها می تواند به محققان در این باره که چگونه حیات از یک دهانه آتشفشان به دهانه ای دیگر متفاوت است، کمک کند.

با وجود دستیابی به این یافته ها، محققان درباره آینده این منطقه که در بستر اقیانوس قرار دارد، ابراز نگرانی کرده اند.

چین توانسته از مجمع بین المللی حفاظت از بستر دریاها برای اکتشاف در دهانه آتشفشان های این منطقه به منظور استخراج مواد معدنی گواهی دریافت کند.

اما پروفسور کاپلی با اشاره به اندازه دهانه این آتشفشان می گوید:"دهانه این آتشفشان به اندازه چند زمین فوتبال است و به نظر می رسد احتمالا موجودات بیشتری را بتوان در این منطقه شناسایی کرد و عاقلانه نیست که این منطقه را قبل از این که واقعا پی ببریم چه تعداد جاندار در آن زندگی می کند، تخریب کنیم."




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