Self-compatibility (SC)
SI is not universal in flowering plants. Indeed, a great many species are self-compatible (SC). The best estimates indicate that approximately one half of angiosperm species are SI. Pollinator decline, variability in pollinator service, and life history traits that are associated with weediness, and the so-called "automatic advantage" of self-fertilisation, among other factors, may favor the loss of SI. As a result, mutations that break down SI (result in SC) may become common or entirely dominate in natural populations. Similarly, human-mediated artificial selection through selective breeding may be responsible for the commonly observed SC in cultivated plants. SC enables more efficient breeding techniques to be employed for crop improvement.
Read more about this topic: Self-incompatibility In Plants