甘蓝型油菜隐性核不育系S45AB的遗传

INHERITANCE OF RECESSIVE GENIC MALE STERILE LINE“S45AB”OF RAPE(Brassica napus L.)

以四川大学选育的油菜隐性核不育系 S45AB 为材料,用不同品种的自交系与 S45A测交、回交、反回交和可育株自交,研究其遗传性。结果表明:S45AB 的不育性是由二对隐性重叠基因 s_1和 s_2控制的(因它来自 S45AB,故取 s_1、s_2为基因符号)。不育株的基因型只有一种,即双隐性纯合体 s_1s_1s_2s_2;二对基因中只要有一个基因为显性时都是可育株,其中有一对基因为显性纯合S_1S_或 S_2S_2的可育株就可作为恢复系,故它具有广泛的恢复系;采用兄妹交配 s_1s_1s_2s_2×S_1s_1s_2s_2 或s_1s_1s_2s_2×s_1s_1S_2s_2,其后代的育性分离都能稳定在1∶1。在杂种优势利用时可采用二系法制种,还可以做为利用杂种二代的材料。本文通过显性核不育系与隐性核不育的遗传比较,以加深对核不育性遗传的理解。

The study on inheritance of recessive genic male sterile line “S45AB”coming from sichuan University was carried out by test-crossing,back-crossing and reciprocal back- crossing with various B.napus varieties and self-crossing of some fertile plants.The results showed that the sterility of “S45AB” is controlled by two pairs of recessive genes with dupli- cate effect.Only s_1s_1s_2s_2 is the genotype of the sterile plants,the others are fertile.The genotypes with S_1S_1,S_2S_2 or S_1S_1S_2S_2 are all restorer lines.So this line has wide restorer lines.The ratio of fertility segregation in next generation from sib-mating of the two lines (s_1s_1s_2s_2×S_1s_1s_2s_2)and (s_1s_1s_2s_2×s_1s_1S_2s_2)is stably 1:1.In practice,this line can be used to produce hybrid seeds with two-line method,and can be utilized as the parent for heterosis u- tilization of F_2 generation.In this paper the authors made comparison between dominant genic male sterile line and recessive genic male sterile line. This will deepen an understanding of genic male sterility.