Apomixis: The asexual formation of seed

Abstract

Apomixis is the clonal production of a plant through seed. It is a naturally occurring trait that has been studied for many years but the tools necessary to dissect it at the molecular level have been available only recently. Significant advances have been made in the study of both naturally occurring apomicts and mutants of sexual species that mimic the component events of apomixis. Results reveal the potential mechanisms of control, the possible evolutionary origins of apomixis and the impacts it has had on the evolution of species and genomes. Apomixis leads to the formation of genetically uniform populations and these can persist over many seedling generations. This makes it a potentially attractive trait for agriculture as its introduction into crops would significantly increase the rate of breeding gain for seed-propagated crops and it would simplify the production of hybrid populations for commercial use. It is now generally agreed that apomixis is a genetically controlled trait and that it should be possible to engineer it into crops once the correct elements are in place. The final format of such an engineered form of the trait may, or may not, reflect known natural mechanisms, and it may differ between crops, catering for unique aspects of the reproductive biology in each recipient species.