Study on the mating systems of wild rice Oryza rufipogon and O. nivara and their effects on population genetic variation

As the wild ancestors of Asian cultivated rice, Oryza rufipogon Griff. and
O. nivara Sharma et Shastry serve as valuable germplasms for rice
breeding. Mating systems are important in shaping the level and pattern of
population genetic variation, and are crucial for germplasm conservation.
We genotyped 12 simple sequence repeats (SSR) markers for a large number
of maternal plants and seeds collected from O. rufipogon and O. nivara
populations distributed in Southeast Aisa and South China. Based on the 12
SSR markers, we estimated the outcrossing rates and other parameters of
the mixed-mating model for the two wild rice species. We also assessed the
level of genetic diversity and population structure for parental
populations of O. rufipogon and O. nivara. Our study could facilitate in
situ and ex situ conservation, and the utilization of these valuable
germplasm resources.