Du Jin-Kun, Yao Ying-Yin, Ni Zhong-Fu, Peng Hui-Ru, Sun Qi-Xin
Department of Plant Genetics & Breeding, China Agricultural University, Beijing 100094, China.
Yi Chuan Xue Bao. 2002 May;29(5):445-52.
It is important to estimate the genetic diversity between the parents for improving the heterosis of hybrid wheat. In this study, ISSR(inter-simple sequence repeat) marker was used to measure the genetic diversity within and among common wheat (Triticum aestivum L.), spelt (Triticum spelta L.), compactum (Triticum compactum Host.) and progeny of foreign wheat-based recurrent selection, and the possibility of establishing the new heterotic group was also assessed. Forty seven genotypes were used for ISSR analysis, which included 14 common wheat, 10 spelt wheat, 11 compactum and 12 progeny of recurrent selection. Eleven of 33 ISSR primers that can produce distinguishable bands were selected for PCR amplification. A total of 238 bands were amplified, among which 207 (87%) bands were polymorphic. The polymorphic bands amplified by each primer ranged from 11 to 38, with an averaged of 18.8. The percentage of polymorphic band (80.3%) in common wheat was higher than that in progeny of recurrent selection (78.7%), spelt (75.0%) and compactum (74.9%). The 238 polymorphic products were used to calculate Nei's similarity index (GS) and the genetic distance (GD). It was found that the mean genetic distance between different wheat types (0.3115-0.3442) was obviously higher than that within common wheat (0.2743), spelt (0.2351), compactum (0.2622). In addition, progeny of recurrent selection also showed much higher genetic distance with other three wheat types (0.3217, 0.3256, 0.3198). The cluster analysis was performed based on the genetic distance (GD) matrix by using UPGMA method. Common wheat, spelt, compactum and progeny of recurrent selection were classified into four different groups. In this study, ISSR marker was firstly used to assess genetic diversity among common wheat, spelt, compactum and progeny of recurrent selection, and can differentiate the wheat cultivars (lines) that selected from the same cross combination. It was concluded that spelt, compactum and progeny of recurrent selection can be used to diversify the genetic basis for hybrid wheat breeding and improve heterosis. It is possible to establish the wheat heterotic group by ISSR marker.
为提高杂交小麦的杂种优势，估算亲本间的遗传多样性很重要。本研究利用ISSR（简单序列重复区间）标记来测定普通小麦（Triticum aestivum L.）、斯卑尔脱小麦（Triticum spelta L.）、密穗小麦（Triticum compactum Host.）以及外源小麦轮回选择后代的遗传多样性，并评估建立新杂种优势群的可能性。47个基因型用于ISSR分析，其中包括14个普通小麦、10个斯卑尔脱小麦、11个密穗小麦和12个轮回选择后代。从33条能产生清晰条带的ISSR引物中选出11条用于PCR扩增。共扩增出238条带，其中207条（87%）为多态性条带。每条引物扩增出的多态性条带数在11至38条之间，平均为18.8条。普通小麦的多态性条带百分比（80.3%）高于轮回选择后代（78.7%）、斯卑尔脱小麦（75.0%）和密穗小麦（74.9%）。利用这238个多态性产物计算Nei氏相似性指数（GS）和遗传距离（GD）。发现不同小麦类型间的平均遗传距离（0.3115 - 0.3442）明显高于普通小麦（0.2743）、斯卑尔脱小麦（0.2351）、密穗小麦（0.2622）内部的遗传距离。此外，轮回选择后代与其他三种小麦类型的遗传距离也较高（0.3217、0.3256、0.3198）。采用UPGMA方法基于遗传距离（GD）矩阵进行聚类分析。普通小麦、斯卑尔脱小麦、密穗小麦和轮回选择后代被分为四个不同的类群。本研究首次利用ISSR标记评估普通小麦、斯卑尔脱小麦、密穗小麦和轮回选择后代的遗传多样性，并能区分同一杂交组合选育出的小麦品种（系）。得出结论，斯卑尔脱小麦、密穗小麦和轮回选择后代可用于拓宽杂交小麦育种的遗传基础并提高杂种优势。利用ISSR标记建立小麦杂种优势群是可行的。
