Editing Self-incompatibility (section)

{{Short description|Biological reproductive mechanism component}}
'''Self-incompatibility''' ('''SI''') is a general name for several genetic mechanisms that prevent [[self-fertilization]] in [[sexual reproduction|sexually reproducing]] organisms, and thus encourage [[outcross]]ing and [[allogamy]]. It is contrasted with separation of sexes among individuals ([[dioecy]]), and their various modes of spatial ([[herkogamy]]) and temporal ([[dichogamy]]) separation.

SI is best-studied and particularly common in flowering plants,<ref name="igic2008si">{{cite journal | vauthors = Igic B, Lande R, Kohn JR |title=Loss of Self-Incompatibility and Its Evolutionary Consequences |journal=International Journal of Plant Sciences |volume=169|issue=1 |pages=93–104 |year=2008 |pmid= |doi=10.1086/523362 |s2cid=15933118 }}</ref> although it is present in other groups, including [[ascidians|sea squirts]] and [[fungi]].<ref name="sawada2014non-self">{{cite journal | vauthors = Sawada H, Morita M, Iwano M | title = Self/non-self recognition mechanisms in sexual reproduction: new insight into the self-incompatibility system shared by flowering plants and hermaphroditic animals | journal = Biochemical and Biophysical Research Communications | volume = 450 | issue = 3 | pages = 1142–1148 | date = August 2014 | pmid = 24878524 | doi = 10.1016/j.bbrc.2014.05.099 }}</ref> In plants with SI, when a [[pollen]] grain produced in a plant reaches a stigma of the same plant or another plant with a matching allele or genotype, the process of pollen [[germination]], pollen-tube growth, [[ovule]] [[fertilization]], or [[embryo]] development is inhibited, and consequently no [[seed]]s are produced. SI is one of the most important means of preventing [[inbreeding]] and promoting the generation of new [[genotype]]s in [[plant]]s and it is considered one of the causes of the spread and success of [[angiosperm]]s on Earth.