Incompatibility Systems in Fruit Crops: Applications and Achievements

The method of pollination is crucial for fruit crop breeding since it affects the genetic makeup, type of gene action, ease of pollination control, and stability of varieties after release. There are a number of processes that encourage cross-pollination, but self-incompatibility (SI) is particularly significant since it is exploited in the production of hybrid seeds. SI is the practice of not allowing fertile (functioning) male and female gametes from the same plant to fuse together. Since ancient times, breeders and growers have successfully used SI as a tool to modify domesticated crops. Self-incompatibility may have an array of causes, including those that are physical, physiological, biochemical, and molecular, but on a broader scale, it appears that all of these components interact to regulate it. According to molecular investigations, at least two genes in the S-locus regulate the SI, one of which functions as a male and one as a female determinant. Self-incompatibility has several different uses, including marker-assisted breeding through SI genotyping, agricultural production and quality improvement, and the creation of hybrids to get over intra- and interspecific reproductive obstacles.