中国春-柱穗山羊草杀配子染色体2C附加系与小麦-冰草附加系杂交F2的细胞学特性

 【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。

Cytological Traits of F2 Hybrids of Chinese Spring-Ae.cylindryca Host.Gametocidal Chromosome 2C Disomic Addition × Wheat-A.cristatum(L.)Beauv.Addition

Abstract：【Objective】Identify the F2 PMCs chromosome variations of five crosses of wheat-A. cristatum (L.) Beauv. addition lines hybridized with China spring-Ae.cylindryca Host. gametocidal chromosome 2C disomic addition line and the types and frequencies of the chromosome variations induced by gametocidal chromosome in order to construct wheat- A. cristatum (L.) Beauv．translocation lines.【Method】The chromosome variations of F2 PMCs was observed using the routine method and P genome were detected by GISH.【Result】The results showed that plurivalents , multi-univalents , lagging chromosomes and chromosomes fragments was observed in PMCI metaphase in all of F2 hybrid crosses, chromosome bridges in most of crosses and ring chromosomes in very few crosses．The frequencies of F2 aberrant chromosome are as follows in mean : 36.72% cells with plurivalent, 20.16% cells with multi univalent, 30.86% cells and 11.7% cells with fragments and chromosome bridges respectively. Multifid quadrants and retrogression were observed in PMCI metaphase in certain crosses. Many different size microkernels are observed in dimidiate and quadrants. Five crosses had different self seed setting percentage from 23.9% to 40.95%. The result showed that the P genome usually was univalent in some F2 crosses detected by GISH．【Conclusion】These aberrations of chromosome behaviors indicated that the gametocidal chromosome was effective in the meiosis of the formation of gametes. The gametocidal chromosome 2C had a different effect on fertility in various wheat-Agropyron chromosome addition lines.