Inheritance of male sterility in a thermo-sensitive genic male sterile line of non-pollen type XianS in rice

【Objective】 XianS,a mutant from traditional variety Xianhuangzhan,is a thermo-sensitive genic male sterile line of non-pollen type in rice in Guangzhou.Studies were conducted on the genetic character of sterility of XianS in order to further research and use in production.【Method】 In this experiment,the classical genetic method was adopted to study the law of the genetic character of sterility of XianS by several fertility investigations on F1,F1(cross and reciprocal cross),F2 and BCF1 and male sterility of F2 sterile plants,generations of the rice by the cross of XianS with several conventional rice varieties.【Result】 In Guangzhou(23°08′N),XianS had sterility from early May to late October,and its stage of sterility was longer than Pei'ai 64S for almost 2 months.The sterility of XianS,a thermo-sensitive genic male line could be rather highly recovered by several different rice varieties,indicating that the male sterility was a recessive character.The fertility rates of F1(cross and reciprocal cross)were not significantly different,indicating that the male sterility was controlled by nuclear gene.The rate of sterility to fertility in every combination among 35 F2 combinations from XianS with 39 traditional varieties followed 1∶3.The distribution of fertile plants and sertile plants was discontinuous and extremly segregate.The rate of sterility to fertility in every combination among 13 combinations(back cross) from XianS with 13 traditional varieties followed 1∶1,indicating that the male sterility was controlled by one pair of gene.According to the investigations on sterile plants of F2 combinations from XianS with conventional rice varieties more than 10,their fertility conversions were similar to XianS'.The pattern of pollen abortion was non-pollen type at last.Every sterile plant had thermo-sensitivity.【Conclusion】 The result showed that in Guangzhou the inheritance of sterility of XianS was recessive and controlled by nuclear gene and that the feature of sterility of XianS was basically in such a model:Controlled by one pair of major gene.The pattern of pollen abortion and thermo-sensitivity could be inherited.