Advances in molecular genetic mechanism of meiotic recombination and applications in crop breeding

Meiosis is essential for producing haploid gametes during sexual reproduction in most eukaryotes. Homologous recombination is one of the critical events of meiosis prophase I. It not only leads to the reshuffle of genetic information between homologs, but also ensures their proper segregation at anaphase I. Therefore, meiotic recombination is important to facilitate the genetic diversity and evolution among progeny, and also provides the theoretical basis for crop breeding. As expectedly, increasing the frequency of recombination or changing its distribution can benefit crop breeding, while reducing or inhibiting recombination can sustain heterosis. Over the past decades, numerous achievements have been made in understanding and utilizing meiotic recombination in plants, including mechanisms on genetic and epigenetic regulation of meiotic recombination, manipulation technologies on recombination, fixation of heterosis and chromosome engineering. In this review, we summarize the latest findings and technologies for regulating meiotic recombination, which will enable the readers to have an easy access to understand meiotic recombination, and also expand the idea of manipulating breeding through meiotic recombination.