Gene-by-gene And Gene-by-environment Interaction Of Four Genes For Hybrid Sterility Between Oryza Sativa And O. Glaberrima

Oryza sativa and O.glaberrima, share the same AA genome, are the only two cultivated species in the24species of Oryza. Possessing resistance to many viruses and pests, O.glaberrima has become the best choice for O. sativa to broaden its genetic varieties. However, hybrid sterility hampers the genetic transfer between them severely. A series of hybrid sterility genes from O. glaberrima have been found to be the main cause of hybrid sterility, which is not just controlled by only one sterile gene. Additionally, the environmental factors contributed a lot to the hybrid sterility. Hence the gene-by-gene (GxG) and gene-by-environment (G×E, G×G×E) interaction are needed to be clarified.To further understand the G×G, G×E and G×G×E interaction of the four hybrid sterility genes between two cultivated rice Oryza sativa and O. glaberrima, four Near Isogenic Lines (NILs) in BC7F10generations included NIL-S1, NIL-S20, NIL-S33(t) and-NIL-S37(t), which were bred by the YAAS research team, were used to cross with each other to obtain F1generations. And the BC8F1generations were derived from Dianjingyou1(DJY1) and the four NILs, respectively. DJY1, the F1and BC8F, generations were all planted in the2010Winter Crop Season(Jan-June,2011) and the2011Late Crop Season (Aug-Nov,2011) in Sanya, China.The results showed as follows:1, The daily maximum air temperature, the photoperiod and the rainfall in the flowering time are the very important factors to the pollen and spikelet fertility;2, Accumulative effect acts on pollen fertility. It performed that the pollen fertility of BC8F1generations were around50%while F1generations ranged from9.12-37.86%in both seasons;3, Environmental factors and G×G effects contributed quite a lot in the G×G×E interactions of the F1generations.4, The results of BC8F1G×E interactions presented significant difference of the pollen fertility between two seasons in the genotype of SI and S20while S33(t) and S37(t) were reluctant to react with the environment;5, The difference of pollen abortion types between two seasons in F1generations implied that the environmental factors or G×G×E interactions might have effect on them to some extent.To further understand the genetic model of sterile genes, this research provided new evidences and will be an important way to study and use the genetic varieties of O.glaberrima.