重庆温光型小麦雄性核不育系C_(49s)细胞遗传学研究

CYTOGENETIC STUDIES OF THE CHONGQING THERMO-PHOTOPERIOD SENSITIVE MALE STERILITY WHEAT LINE C_(49s)

通过对重庆温光型雄性核不育系“C4 9s” ,普通小麦“6 9” ,“C4 9s”与普通小麦杂种F1花粉母细胞减数分裂行为的观察发现 ,“C4 9s“花粉母细胞减数分裂行为基本正常 .但在其杂种F1花粉母细胞中未观察到 2 1个环状二价体 ,而出现了较多的三、四价体 .这表明 ,两亲本材料在染色体结构上至少有一对染色体发生了结构变异 .通过根尖有丝分裂中期细胞观察发现 ,“C4 9s”仅具 1对随体染色体 ,而在“栽培二粒”及“6 9”中 ,均具有 2对随体染色体 ,杂种F1中均含有 3条随体染色体 .Ag NOR显带观察 ,发现在“C4 9s”中只有 2条染色体显示非常明显的Ag NOR带 ,在“6 9”中却有 4条染色体显示Ag NOR带 .由此可见 ,“C4 9s”不育系有一对具随体染色体核仁组织区及随体发生了缺失 .核型分析发现 ,发生缺失的染色体可能为 1B .这可能是导致“C4 9s”表现温光型核不育的主要原因 .

Meiotic analysis of the chongqing thermo photoperiod sensitive male line “C 49s ”, Triticum aestivum cv. “69” and their F 1 hybrid showed that the chromosome pairing of “C 49s ” and “69” were all regular, few of 21 ring bivalents but many multivalents (trivalents and quadrivalents) were scored in the F 1 hybrid, during to at least a pair chromosome aberration. Karyotype analaysis of RTC (Root tip cell) further recovered 4 satell...