利用普通小麦品种绵阳11作母本,抗病的威宁黑麦(Sceale cereale L.)作父本,在其杂交和回交后代中分别鉴定出一个1R和5R单体附加系。为获得新的1BL·1RS初级易位系以及小麦-黑麦5R染色体易位,采用基因组原位杂交和荧光原位杂交相结合的方法,对1R和5R单体附加系的自交后代进行了鉴定。在1R单体附加系的后代中,筛选到一个纯合1R(1B)染色体代换系和一个新的纯合1BL·1RS初级易位系。该1R(1B)代换系表现出比小麦亲本较差的农艺性状;新1BL·1RS初级易位系表现出比其小麦亲本更好的农艺性状以及条锈病和白粉病抗性,而且穗粒数显著增加,是高产抗病小麦育种的新资源。在5R单体附加系的后代中,筛选出一个涉及3BS染色体片段与5RL的易位,发生易位的植株占分析植株总数的1.89%。5R染色体单体附加极其不稳定,在一个世代交替中完整的5R染色体传递率仅有28.3%。除自身的不稳定外,5R染色体单体附加同时导致小麦染色体7B、3B和4D的断裂和丢失,总变异频率达到15.09%;尤其对7B染色体影响较大,含7B染色体变异的植株占分析植株总数的11.32%。5R染色体单体附加诱导的小麦和黑麦染色体的高度不稳定现象值得进一步研究。
Two wheat-rye monosomic addition lines with 1Ror 5Rwere selected from the descendants of a cross between wheat cultivar Mianyang11(MY11)and rye(Sceale cereale L.)variety Weining,respectively.In order to obtain new 1BL·1RS primary translocation line and wheat-rye 5Rchromosome translocation line,the selfed progenies of the 1Rand 5R monosomic addition lines were identified by means of GISH(Genomic in situ hybridization)and FISH(Fluorescence in situ hybridization).One 1R(1B)substitution line and one 1BL·1RS translocation line were identified from the selfed progenies of the 1Rmonosomic addition line.The new primary 1BL·1RS translocation line exhibited better agronomic characters and resistance to rust stripe and powdery mildew than its wheat parent.A translocation between the segments of wheat chromosome 3BS and rye chromosome 5RL with a frequency of 15.09% was identified from the selfed progenies of the 5Rmonosomic addition line.The 5Rchromosome showed very instability in the monosomic addition line,in which only 28.3%transmission ratewas exhibited.The breakage and deletion of wheat chromosomes 7B,3Band 4Dwere observed in the selfed progenies of 5Rmonosomic addition line with a total frequency of 15.09%,in which a high frequency of 11.32% was found for the chromosome 7B.The translocation frequency between different wheat and rye chromosomes and their genetic relationship was discussed.