籼稻体细胞无性系雄性不育突变的类型

Types of Male Sterile Mutants in Somaclones from Somatic Cell Culture of Indica Rice

1984—1988年5年间所获得的由体细胞无性系变异起源的雄性不育突变,按它们的性质,可分为花粉败育型,无花粉型和花药退化(或部分退化)型3类。在IR54中,于不同年份(1985和1986年)及不同世代(R_1和R_2代)发现了表型基本相似,基因型可能也相似的两例无花粉型雄性不育突变。在花粉败育型雄性不育突变中,发现1例(54257)为核质互作型雄性不育。以多个品种与之测交,杂种一代中有的表现为育性恢复,有的仍然为雄性不育。能保持其雄性不育的品种有珍汕97、二九矮、新锦粘、162-5(来自IR 52的稳定的体细胞无性系),连续回交3代以上均能基本保持不育(但桂朝2号的回交后代不育性尚不稳定)。能使其育性恢复的品种有IR 24、IR 36、IR 54、双二粘、测64等。初步遗传研究表明,54257表现出十分复杂的核质关系,看来可能具有与野败细胞质完全不同的特性。

During the five years of 1984-1988, 48 cases of male sterile mutants in nine varieties were found, in which 20 cases belonged to R1 generation and 28 R2 generation. The frequency of ms variations in R1 generation was around 1% and the one in R1 generation, 2%.According to the characters of ms-mutants and their genetic expression, they could be classified into pollen free (nuclear sterile) and pollen abortive (cytoplasmic and genetically controlled). In IR 54, two cases of pollen free ms-mutant appeared in different generations (R1 and R2 generations) in lifferent vears (1985 and 1986) were found to be exactly the same In other words, an identical ms-mutant was repeatedly induced in different years and different generations by somatic cell culture in rice.Among ms-mutants of the abortive pollen type, one (cole '54257') was found to be the cytoplasmic and genetically controlled male sterile mutant. Zhengshan 97, Erjiuai and 162-5 (a stable somaclone from IR 52) could ?maintain the male sterility of 54257. And IR 24, IR 36, IR 54, Shuangerzhan and so on could restore the fertility. According to the results of continuously back-crossing (BC) for 4 times, the capacity of Zhengshan 97, Erjiuai and 162-5 for maintaining the ms of 54257 was stable. The BC hybrids were completely male sterile. This result showed that the mutant 54257 was ms-mutant controlled by cytoplasmic gene. This is the first report of this kind of mutant derived from sonraclones of crops in the world.The ms-line derived from the mutant 54257 showed that different characters depended upon the maintainer. When Zhengshan 97B used as the maintainer was backcrossed with 54257, the BC hybrid (54257 · Zhengshan 97A) expressed as the CMS line with WA cytoplasm. But when 162-5 as the maintainer was backcrossed to 54257, the BC hybrid (54257·162-5 A) showed quite different from the CMS line with WA cytoplasm.