|THE EDIBLE PLANTS IN VIETNAM||
Edited by Ho Dinh Hai
Long An - Vietnam
Plant ovules: Gymnosperm ovule on left, angiosperm ovule (inside ovary) on right
After fertilization the ovules develop into the seeds. The ovule consists of a number of components:
- The funicle (funiculus, funiculi) or seed stalk which attaches the ovule to the placenta and hence ovary or fruit wall, at the pericarp.
- The nucellus, the remnant of the megasporangium and main region of the ovule where the megagametophyte develops.
- The micropyle, a small pore or opening in the apex of the integument of the ovule where the pollen tube usually enters during the process of fertilization.
- The chalaza, the base of the ovule opposite the micropyle, where integument and nucellus are joined together).
The shape of the ovules as they develop often affects the final shape of the seeds. Plants generally produce ovules of four shapes: the most common shape is called anatropous, with a curved shape. Orthotropous ovules are straight with all the parts of the ovule lined up in a long row producing an uncurved seed. Campylotropous ovules have a curved megagametophyte often giving the seed a tight "C" shape. The last ovule shape is called amphitropous, where the ovule is partly inverted and turned back 90 degrees on its stalk (the funicle or funiculus).
In the majority of flowering plants, the zygote's first division is transversely oriented in regards to the long axis, and this establishes the polarity of the embryo. The upper or chalazal pole becomes the main area of growth of the embryo, while the lower or micropylar pole produces the stalk-like suspensor that attaches to the micropyle. The suspensor absorbs and manufacturers nutrients from the endosperm that are used during the embryo's growth.
In gymnosperms, which do not form ovaries, the ovules and hence the seeds are exposed. This is the basis for their nomenclature - naked seeded plants (gymnosperms).
In plants, the embryo is the fertilised ovule, an immature plant from which a new plant will grow under proper conditions. The embryo has one cotyledon or seed leaf in monocotyledons, two cotyledons in almost all dicotyledons and two or more in gymnosperms.
In the fruit of grains (caryopses) the single monocotyledon is shield shaped and hence called a scutellum. The scutellum is pressed closely against the endosperm from which it absorbs food, and passes it to the growing parts. Embryo descriptors include small, straight, bent, curved and curled.
The main components of the embryo are:
-The cotyledons, the seed leaves, attached to the embryonic axis. There may be one (Monocotyledons), or two (Dicotyledons). The cotyledons are also the source of nutrients in the non-endospermic dicotyledons, in which case they replace the endosperm, and are thick and leathery. In endospermic seeds the cotyledons are thin and papery. Dicotyledons have the point of attachment opposite one another on the axis.
-The epicotyl, the embryonic axis above the point of attachment of the cotyledon(s).
-The plumule, the tip of the epicotyl, and has a feathery appearance due to the presence of young leaf primordia at the apex, and will become the shoot upon germination.
-The hypocotyl, the embryonic axis below the point of attachment of the cotyledon(s), connecting the epicotyle and the radicle, being the stem-root transition zone.
-The radicle, the basal tip of the hypocotyl, grows into the primary root.
Monocotyledonous plants have two additional structures in the form of sheaths. The plumule is covered with a coleoptile that forms the first leaf while the radicle is covered with a coleorhiza that connects to the primary root and adventitious roots form from the sides. Here the hypocotyl is a rudimentary axis between radicle and plumule. The seeds of corn are constructed with these structures; pericarp, scutellum (single large cotyledon) that absorbs nutrients from the endosperm, plumule, radicle, coleoptile and coleorhiza-these last two structures are sheath-like and enclose the plumule and radicle, acting as a protective covering.
Seed Leaf of Monocots
Monocots have only one seed leaf inside the seed coat. It is often only a thin leaf, because the endosperm to feed the new plant is not inside the seed leaf.
When a monocot seed germinates, it produces a single leaf. It is usually long and narrow, like the adult leaf. Even when it is quite a round shape, there is only one seed leaf in a monocot.
Seed Leaves of Dicots
Dicots have two seed leaves inside the seed coat. They are usually rounded and fat, because they contain the endosperm to feed the embryo plant.
When a dicot germinates, it produces two seedleaves. They contain the food for the new plant, so they are usually fatter than the true leaves. The first true leaves are often a different shape.
+Vicia : V. faba or broad bean
-V. aconitifolia or Moth bean
-V. angularis or azuki bean
-V. mungo or urad bean
-V. radiata or mung bean
-V. subterranea, Bambara bean or ground-bean
-V. umbellatta or ricebean
-V. unguiculata or cowpea (includes the black-eyed pea, yardlong bean and others)
+ Cicer : C. arietinum or chickpea (also known as the garbanzo bean)
+ Lens : L. culinaris or lentil
+ Lablab : L. purpureus or hyacinth bean
- P. acutifolius or tepary bean
- P. coccineus or runner bean
- P. lunatus or lima bean
- P. vulgaris or common bean (includes the pinto bean, kidney bean, black bean, as well as green beans, and many others)
- P. polyanthus (aka P. Dumosus, recognized as a separate species in 1995)
- G. max or soybean
- P. tetragonolobus or winged bean
- C. cajan or pigeon pea
- S. spp or velvet bean
- C. tetragonoloba or guar
- C. ensiformis or jack bean
+ Canavalia gladiata or sword bean
- M. uniflorum or horse gram
+ Lupinus or Lupin
- L. mutabilis or tarwi
- Lupinus albus or lupini bean
- E. herbacea or Coral bean
-A. hypogaea or Peanut
True, or botanical nuts
Johnstone River almond
Red bopple nut
Queensland macadamia nut