摘要
The behavior of wheat-rye translocation chromosome and alien chromosome including Thinopyrum and Haynaldia chromosome at meiosis was investigated in two hybrids by fluorescence in situ hybridization (FISH). Misdivision of translocation chromosome at anaphase I and rye chromatin micronucleus at tetrad stage were observed, A plant with one normal 1BL/1RS translocation chromosome and one 1BL/1RS translocation chromosome deleted about 1/3 of rye chromosome arm in length was identified. One plant with wheat-Thinopyrum non-Robertson translocation chromosome was also detected in the F-2 population of Yi4212 x Yi4095. That could be the results of unequal misdivision of wheat-rye 1BL/1RS translocation chromosome and Thinopyrum chromosome during meiosis. No interaction between translocation chromosome and alien chromosome at meiosis was supported by the data of the distribution frequencies of translocation chromosome and Thinopyrum or Haynaldia chromosome in the progeny of two hybrids. The results may be useful to cultivate new germplasms with different length of rye 1R short arm and wheat-alien non-Robertson translocation tines under wheat background.
利用荧光原位杂交技术分析了两个小麦_外源种杂种花粉母细胞中 1BL/1RS小麦_黑麦易位染色体和外源染色体包括中间偃麦草 (Thinopyrumintermedium (Host)Barkworth&DRDewey)、簇毛麦 (Haynaldiavillosa (L .)Schur)染色体的减数分裂行为。我们首次发现 :在减数分裂后期 ,1BL/1RS小麦_黑麦易位染色体发生错分裂 ,形成两个易位染色单体。这种错分裂导致易位染色单体在末期Ⅰ分配到两个正在形成的细胞核内 ,错分裂的易位染色单体进一步形成微核 ,并在四分体期观察到黑麦的微核出现。从贵农 2 2×遗 40 95的F2 代植株中检测到一个 2n =41的植株 ,其含有一对 1BL/1RS小麦_黑麦易位染色体 ,核型分析表明 ,其中一条黑麦染色体臂比另一条的黑麦染色体臂短 1/3左右。在遗 42 12×遗 40 95的F2 代中检测到一个具有中间偃麦草染色体小片段易位到小麦染色体端粒部分的小麦_中间偃麦草易位植株。这可能是由于在减数分裂过程中发生非均等分裂导致小麦_黑麦 1BL/1RS易位染色体的黑麦染色体段臂缺失 1/3及小麦_中间偃麦草非罗伯逊易位。在两个杂种F2 植株中 ,中间偃麦草染色体分布频率为 39.6 % ,簇毛麦染色体分布频率为 43.4% ,1BL/1RS小麦_黑麦易位染色体分布频率分别为 5 1.8%和5 6 .6 %。实验结果表明 ,1BL/1RS小麦_?
基金
中国科学院知识创新工程生物领域重点项目资助 (KSCX2_1_0 1_2_0 2 )~~
