Genetic Diversity of Genes Controlling Unilateral Incompatibility in Japanese Cultivars of Chinese Cabbage.

In recent years, unilateral incompatibility (UI), which is an incompatibility system for recognizing and rejecting foreign pollen that operates in one direction, has been shown to be closely related to self-incompatibility (SI) in . The stigma- and pollen-side recognition factors ( and , respectively) of this UI are similar to those of SI (stigma-side and pollen-side ), indicating that and interact with each other and cause pollen-pistil incompatibility only when a specific genotype is pollinated. To clarify the genetic diversity of and in Japanese , here we investigated the UI phenotype and the / sequences in Japanese commercial varieties of Chinese cabbage. The present study showed that multiple copies of nonfunctional were located within and in the vicinity of the locus region, and that the functional was highly conserved in Chinese cabbage. In addition, we found a novel nonfunctional allele with a dominant negative effect on the functional allele in the heterozygote.