Hexaploid triticale is an important genetic resource for genetic improvement of common wheat, which can broaden the genetic basis of wheat. In order to lay a foundation for the subsequent research and utilization of triticale germplasm materials, the chromosomal genetic characteristics of cross and backcross offspring of hexaploid triticale×hexaploid wheat were investigated in the process of transferring rye chromatin from hexaploid triticale to hexaploid wheat. Hybrid and backcross combinations were prepared with hexaploid triticale 16yin171 as the maternal parent and hexaploid wheat Chuanmai62 as the paternal parent. The chromosomes in root tip cells of F1, BC1F1 and BC1F2 plants were traced and identified non-denaturing florescence in situ hybridization (ND-FISH). The results indicated that the backcross setting rate of hybrid F1 was 2.61%. The transmission frequency of 2R chromosome was the highest in BC1F1 plants while the transmissibility of rye chromosome in BC1F2 plant was 6R>4R>2R, and the 5B-7B wheat translocation in BC1F2 plants showed severe segregation. A total of 24 structural variant chromosomes were observed both in BC1F1 and BC1F2 plants, including chromosome fragments, isochromosomes, translocations, and dicentric chromosomes. In addition, the seed length and 1000-grain weight of some BC1F2 plants were better than that of the hexaploid wheat parent Chuanmai 62. Therefore, multiple backcrosses should be adopted as far as possible to make the rapid recovery of group D chromosomes, ensuring the recovery of fertility in offspring, when hexaploid tritriale is used as a bridge to introduce rye genetic material into common wheat. At the same time, the potential application value of chromosomal structural variation materials should be also concerned.
六倍体小黑麦是普通小麦品种遗传改良的重要基因资源，可以拓宽小麦的遗传基础。本研究以六倍体小黑麦为供体向普通小麦转移黑麦染色质，以探明六倍体小黑麦×六倍体小麦杂交、回交后代的染色体遗传特性，为小黑麦种质材料的后续研究和利用奠定基础。以六倍体小黑麦16引171为母本，六倍体小麦川麦62为父本配制杂交及回交组合，利用非变性荧光原位杂交技术(non-denaturing florescence in situ hybridization，ND-FISH)对F1、BC1F1和BC1F2植株进行细胞学跟踪鉴定。结果表明，杂种F1回交结实率为2.61%；BC1F1植株2R染色体传递频率最高；BC1F2植株中黑麦染色体在后代的传递率为6R>4R>2R，小麦背景中5B-7B相互易位染色体在BC1F2植株中表现出严重偏分离。在BC1F1和BC1F2植株中观察到24种结构变异染色体，包括染色体片段、等臂易位染色体、易位染色体以及双着丝粒染色体，且部分BC1F2植株的种子表现粒长和千粒重均优于六倍体小麦亲本川麦62。因此，在利用六倍体小黑麦作为桥梁向普通小麦导入黑麦遗传物质时，应尽量采取多次回交的方式，使D组染色体迅速恢复，保证后代育性的恢复，同时关注染色体结构变异材料的潜在应用价值。.
Keywords: ND-FISH; chromosomal inheritance; chromosome structural variation; hexaploid triticale; hexaploid wheat.