S-RNase encoded by gametophytically self-incompatible S-gene in plant pistil is an enzyme which causes pollen mRNA or rRNA of plants with identical genotypes to be degraded, resulting in self-incompatibility in plants. The fruiting percentage is less than 10% when cultivars with the same S-gene pollinate each other, but it reaches 60-100% in cultivars with different S-gene. China is rich in species or cultivars in pears (Pyrus spp.), and there are more than 500 cultivars only in Pyrus pyrifolia. However, the genetic resources and S genotypes are not yet clear in those cultivars. In this paper,...
