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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.
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 ...
Cross-pollination involves the transfer of pollen grains from the flower of one plant to the stigma of the flower of another plant. The main characteristics which facilitate cross-pollination are: Herkogamy : Flowers possess some mechanical barrier on their stigmatic surface to avoid self-pollination, e.g. presence of gynostegium and pollinia ...
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 ...
Allogamy ordinarily involves cross-fertilization between unrelated individuals leading to the masking of deleterious recessive alleles in progeny. [11] [12] By contrast, close inbreeding, including self-fertilization in plants and automictic parthenogenesis in hymenoptera, tends to lead to the harmful expression of deleterious recessive alleles (inbreeding depression).
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).
However, as opposed to 'complete' or 'absolute' SI, in CSI, self-pollination without the presence of competing cross pollen, results in successive fertilization and seed set; [45] in this way, reproduction is assured, even in the absence of cross-pollination. CSI acts, at least in some species, at the stage of pollen tube elongation, and leads ...
Chasmogamy is the type of plant reproduction in which the flowers open up, enabling cross-pollination. This is in contrast to cleistogamy, in which the flowers stay closed and self-pollinate. Chasmogamous flowers are commonly showy with open petals encircling exposed reproductive parts.