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【目的】对5个小麦-冰草附加系与中国春-杀配子染色体2C附加系杂交F2的减数分裂进行观察,分析杀配子染色体在小麦-冰草附加系背景下诱导染色体变异的有效性,为获得小麦-冰草染色体易位奠定基础。【方法】杂交F2植株幼穗减数分裂染色体行为观察采用常规细胞学方法,冰草P染色质的检测采用GISH方法。【结果】杂交F2PMC减数分裂中期普遍观察到多个单价体、多价体以及落后染色体和断片,多数组合观察到染色体桥,个别组合出现单价环状染色体。杂交F2减数分裂染色体存在异常现象:平均36.5%的细胞中有多个单价体,15.8%的细胞含有多价体,31.6%和11.7%的细胞中含有染色体断片和桥,四分体时期存在微核、多裂和四分孢子退化现象。F2植株的自交结实率平均为31.47%。对部分F2植株的减数分裂细胞GISH检测表明,P染色体多为单体附加,有2.7%的植株可能产生染色体易位。【结论】较高频率的染色体断裂和部分配子致死是杀配子染色体诱导变异的典型特征,柱穗山羊草2C杀配子染色体在小麦-冰草附加系背景下能够有效诱导染色体产生结构变异,这种诱变作用和频率在不同附加系背景下存在差异。
【OBJECTIVE】 To observe the meiosis of chromosome F2 in Chinese wheat-Agropyron addition line and cross of F2 of Chinese spring-gametocidal chromosome, and to analyze the effectiveness of chromosome-matched chromosome mutation in the background of wheat-Agropyron addition line , Which laid the foundation for the wheat-Agropyron chromosome translocation. 【Method】 Chromosomal behavior of young F2 plants in meiosis of spikelets was observed by conventional cytology method. The chromatin of Picea crassipes was detected by GISH method. 【Result】 A number of monovalent, multivalent and late chromosomes and fragments were commonly observed in the metaphase of F2PMC. Chromosome bridges and some combinations of monovalent and circular chromosomes were observed in most combinations. Cross-fertilization F2 meiotic chromosome abnormalities: an average of 36.5% of the cells have multiple monovalent, 15.8% of the cells contain multi-body, 31.6% and 11.7% of the cells contain chromosome fragments and bridges, the existence of quartering Micronuclei, multifission and tetrad spore degeneration. The average self-fertility rate of F2 plants was 31.47%. GISH analysis of meiosis cells in some F2 plants showed that the P chromosome was mostly monomer addition, and 2.7% of the plants might have chromosomal translocation. 【Conclusion】 Chromosome breakage and partial gametocyte death at higher frequencies are the typical characteristics of chromosome-induced variation in gametocidal chromosomes. The chromosomal 2C gamete of goat grass can effectively induce the structural variation of chromosomes in the context of wheat-icy-grass attachment system. Mutagenesis and frequency vary in different contexts.