Xenogamy (also called outbreeding) is a term used to describe the union of genetically unrelated organisms within the same species. Xenogamy promotes genetic variability and vitality within a breeding population by eliminating homozygous individuals. Accordingly, with dominance, lethal or deleterious alleles have a better chance of being repressed by the dominant alleles in heterozygous organisms, thus reducing the impact of lethal or deleterious alleles within a population.

Xenogamy, or outbreeding promotes genetic diversity and thus, also enhances the overall fitness of a species. By producing new and varied combinations, outbreeding is a fundamental part of natural selection and an essential element of evolution. As such, outbreeding is an important tool in the continued survival and evolution of a species.

In plant species, there are several natural mechanisms that can result in xenogamy, including self-incompatibility. With self-incompatibility, there is an inability on the part of sex cells (gametes) from...