硬粒小麦和节节麦是六倍体普通小麦的二级基因源，六倍体人工合成小麦遗传变异丰富、蕴藏着丰富的抗性基因，可供现代小麦改良利用。利用人工合成小麦基因资源与四川小麦杂交、回交，已育成了高产、优质、抗病小麦新品种“川麦42”。本文利用217对微卫星（SSR）引物检测“川麦42”遗传背景中人工合成小麦的导入位点，发现24个位点来源于人工合成小麦，占所用引物数的11.06%，远小于理论值25%。川麦42遗传背景中人工合成小麦导入位点在A、B和D染色体组分布频率不均衡，D组>B组>A组；人工合成小麦导入位点在川麦42各染色体间差异也很大，在1B、2B和5A染色体上分布较集中、片段较长，而在1A等11条染色体上则无导入位点；表明人工合成小麦的遗传位点并不按孟德尔遗传规律传至后代，人工选择压力导致遗传位点很大的偏分离行为。
Triticum durum and Aegilops tauschii are the secondary gene pool of hexaploid common wheat, and their synthetic hexaploid wheat possesses rich genetic diversities and elite genes for common wheat improvement. An elite synthetic hexaploid wheat Syn769 (Decoy1/Aegilops tauschii 188) with beneficial traits such as large kernels and high resistance to stripe rust, was crossed and backcrossed with Sichuan commercial wheat cultivars SW3243 and Chuan 6415, and a high yield potential and good stripe rust resistance wheat cultivar Chuanmai 42 was developed. In the present study, 217 SSR primers were used to reveal the introgression loci of synthetic hexaploid wheat in Chuanmai 42 by comparing Chuanmai 42 with its parents synthetic hexaploid wheat Syn769, and common wheat cultivars SW3243 and Chuan 6415, and 24 synthetic introgression loci in Chuanmai 42 were detected. The frequency of synthetic introgression loci in Chuanmai 42 was 11.06%, which is significantly deviated from the expected segregation ratio 25%. Distribution of synthetic introgression loci in A, B, and D genomes was unbalanced in Chuanmai 42, with the distribution frequency order of D >B >A genomes. Unbalanced distribution of synthetic introgression loci among different chromosomes was also observed. Synthetic chromosome fragments were observed most frequently on chromosomes 1B, 2B and 5A in Chuanmai 42, while non-loci were detected on chromosomes 1A and 10 others. The result indicated that selection stress was the main reason resulting in the significant deviations of synthetic introgression loci from expected segregation ratios. Significant deviations of the expected allele frequencies in the direction of synthetic hexaploid wheat parent Syn769 in Chuanmai 42 can be used to detect chromosomal regions of interest coming from Syn769.
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