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Self-pollination is an example of autogamy that occurs in flowering plants. Self-pollination occurs when the sperm in the pollen from the stamen of a plant goes to the carpels of that same plant and fertilizes the egg cell present. Self-pollination can either be done completely autogamously or geitonogamously. In the former, the egg and sperm ...
Plant species where normal mode of seed set is through a high degree of cross-pollination have characteristic reproductive features and population structure. Existence of self-sterility, [1] self-incompatibility, imperfect flowers, and mechanical obstructions make the plant dependent upon foreign pollen for normal seed set. Each plant receives ...
Allogamy is the fertilization of flowers through cross-pollination, this occurs when a flower's ovum is fertilized by spermatozoa from the pollen of a different plant's flower. [15] [16] Pollen may be transferred through pollen vectors or abiotic carriers such as wind. Fertilization begins when the pollen is brought to a female gamete through ...
Self-pollination is a form of pollination in which pollen arrives at the stigma of a flower (in flowering plants) or at the ovule (in gymnosperms) of the same plant. The term cross-pollination is used for the opposite case, where pollen from one plant moves to a different plant.
Self-compatible (SC) pollination systems are less common than self-incompatibile cross-pollination systems in angiosperms. [11] However, when the probability of cross-pollination is too low it can be advantageous to self-pollinate. Self-pollination is known to be favored in some orchids, rices, and Caulokaempferia coenobialis (Zingiberaceae).
Plants adapted for cross-pollination have several mechanisms to prevent self-pollination; the reproductive organs may be arranged in such a way that self-fertilisation is unlikely, or the stamens and carpels may mature at different times. [8] Self-pollination occurs when pollen from one flower pollinates the same flower or other flowers of the ...
He thought that this observation was amply sufficient to account for outcrossing sexual reproduction. The disadvantages of self-fertilized offspring (inbreeding depression) are now thought to be largely due to the homozygous expression of deleterious recessive mutations; [9] and the fitness advantages of some outcrossed offspring are thought to ...
The basic model is the mixed mating model, which is based on the assumption that every fertilisation is either self-fertilisation or completely random cross-fertilisation. More complex models relax this assumption; for example, the effective selfing model recognises that mating may be more common between pairs of closely related plants than ...