Neutral alleles at hybrid sterility loci of Oryza glaberrima from AA genome relatives in Genus Oryza .

Hybrid sterility between Oryza sativa and O. glaberrima is a main reproduction barrier when transferring the favorable alleles from O. glaberrima to O. sativa and it happens due to allelic interaction at sterility loci. Neutral alleles at each locus have the potential to overcome the sterility between the two cultivated rice species. In this study, an O. sativa cultivar Dianjingyou 1 (DJY1) and its near-isogenic lines (NILs) harboring the single sterility allele S1 -glab, S19 -glab, S20 -glab, S37 -glab, S38 -glab and S39 -glab as the tested lines were crossed with O. glaberrima , O. rufipogon , O. nivara , O. glumaepatula , O. barthii , O. meridionalis and O. sativa so as to detect the neutral alleles of these loci. Pollen fertility was investigated in the paired F1 s based on two seasons' result and genotypic segregation was also analyzed in some F2 populations to confirm the results of pollen fertility investigation. The neutral alleles of S38 -n and S39 -n were identified based upon the pollen fertility and genotypic segregation analysis for the first time. The neutral alleles of sterility loci detected from present report have the potential to know of the nature of interspecific hybrid sterility, and to overcome the interspecific hybrid sterility between O. sativa and O. glaberrima .