利用SSR分子标记技术揭示“硬粒小麦-节节麦”人工合成六倍体小麦的遗传差异

Genetic variation in synthetic hexaploid wheat of 'Triticum durum-Aegilops tauschii' revealed by SSR molecular marker

为引入小麦近缘属种的优良基因和遗传变异、扩宽普通小麦的遗传基础,本文选用36对小麦A,B和D基因组的微卫星引物,对135份人工合成六倍体小麦的遗传多样性进行了评价。36对引物共检测到193个等位变异,每个位点等位变异数在2~14个之间,平均每个位点检测到5.36个等位变异;A,B和D 3个基因组检测到的等位变异数D〉A〉B,遗传多样性指数D〉A〉B。综合平均遗传丰富度和香浓指数两个指标分析结果表明,人工合成六倍体小麦第1和6同源群遗传多样性水平较高,第4和7同源群遗传多样性水平较低;21条染色体中,6D和2D染色体的遗传多样性最高,7D和4B染色体的遗传多样性最低。135份人工合成六倍体小麦遗传相似系数在0.36~0.85之间,平均遗传相似系数A〉B〉D基因组。人工合成六倍体小麦变异类型丰富,是改良普通小麦的重要基因资源。

Wheat relatives with useful genes and rich genetic diversity, could be used for broadening the genetic basis of the common wheat. The genetic diversity of 135 synthetic hexaploid wheats （SHWs） was evaluated by using 36 SSR markers on the A, B and D genomes. Totally 193 alleles were detected on these SSR primer pairs, with an average ot 5.36 alleles per locus. In the three genomes of wheat, the number of alleles was D 〉 A 〉 B, the genetic diversity indexes was D 〉 A 〉 B. The genetic diversity of SHWs was analyzed by the average genetic richness and the genetic diversity indexes. The highest genetic diversity was observed on the homoeologous group 1 and 6 possessed, while the lowest one on the homoeologous group 4 and 7. And chromosome 2D and 6D possessed the highest genetic diversity, while 4B and 7D had the lowest among 21 wheat chromosomes. The genetic similarity coefficient of 135 SHWs varied from 0.36 to 0.85 and the average genetic similarity coefficient A 〉 B 〉 D. The results indicated that SHWs possessed rich genetic variation and is available for common wheat improvment.