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Information about Dehiscent

Dehiscence is the spontaneous opening at maturity of a plant structure, such as a fruit, anther, or sporangium, to release its contents.

Anther dehiscence

This is the final function of the anther that causes the release of pollen grains. The anther wall breaks at a specific site that runs the length of the anther. This site is observed as an indentation between the locules of each theca.

The stomium, and septum are two specialised cell types present at this site. The degeneration of the stomium and septum cells is part of a developmentally timed cell-death program. Initially the septum degenerates thereby establishing the stomium as the future site of anther wall breakage and pollen release. Expansion of the endothecial layer and lignification of the endothecial cell walls are required for dehiscence.

The process of anther dehiscence is coordinated precisely with pollen differentiation, floral development, and flower opening.

Fruit dehiscence

Typically a fruit develops from a gynoecium composed of fused carpels, which, upon fertilization, grow to become a silique that contains the developing seeds. After seed maturation, dehiscence takes place, and valves detach from the central septum freeing the seeds. This is also known as shattering and can be important as a seed dispersal mechanism.

This process is similar to anther dehiscence and the region that breaks (dehiscence zone) runs the entire length of the fruit between the valves and the replum (external septum).

At maturity, the dehiscence zone is effectively a non-lignified layer between a region of lignified cells in the valve and the replum. Shattering occurs due to the combination of cell wall loosening in the dehiscence zone and the tensions established by the differential mechanical properties of the drying cells in the silique.

Association with crop breeding

Manipulation of dehiscence can improve crop yield since a trait that causes seed dispersal is a disadvantage for farmers whose goal is to collect the seed. Many of the agronomically important plants have been bred for reduced shattering.
fruit has different meanings depending on context. In botany, a fruit is the ripened ovary—together with seeds—of a flowering plant. In many species, the fruit incorporates the ripened ovary and surrounding tissues.
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stamen (plural stamina, from Latin stamen meaning "thread of the warp") is the male organ of a flower. Each stamen generally has a stalk called the filament (from Latin filum, meaning "thread"), and, on top of the filament, an anther
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sporangium (pl., sporangia) is a plant or fungal structure producing and containing spores. Sporangia occur on angiosperms, gymnosperms, ferns, fern allies, bryophytes, algae, and fungi. Their spores are sometimes called sporangiospores.
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carpel is the outer, often visible part of the female reproductive organ of a flower; the basic unit of the gynoecium.

Carpel anatomy

The parts of the carpel are:
  • the stigma (from Ancient Greek stigma

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A theca (plural thecae) refers to any case, covering, or sheath.

In botany, the theca of an angiosperm is half of the anther. An anther and its filament form together a typical (or filantherous) stamen, part of the male floral organ.
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Endothecium is a type of tissue found in the walls of anthers and in moss capsules. This tissue is usually one to several layers thick, and is composed of cells that have walls of uneven thickness.
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carpel is the outer, often visible part of the female reproductive organ of a flower; the basic unit of the gynoecium.

Carpel anatomy

The parts of the carpel are:
  • the stigma (from Ancient Greek stigma

..... Click the link for more information.
carpel is the outer, often visible part of the female reproductive organ of a flower; the basic unit of the gynoecium.

Carpel anatomy

The parts of the carpel are:
  • the stigma (from Ancient Greek stigma

..... Click the link for more information.
A silique is a fruit (seed pod) of 2 fused carpels that separate when ripe, leaving a peristant partition, with the length being more than twice the width. This classification includes many members of the Brassicaceae family, but some members, such as Capsella bursa-pastroris L.
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For other meanings of seed, see seed (disambiguation).


SEED

General
KISA
1998

Cipher detail
Key size(s):| 128 bits

Block size(s):| 128 bits
Nested Feistel network
16

SEED
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character is an attribute of an organism that allows it to be compared with another. In genetics this refers to heritable features which can exist in more than one state.[1] A trait
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