黄淮麦区小麦新品系籽粒硬度相关基因分子鉴定及其对产量性状的影响

摘要

[目的] 以黄淮麦区小麦新品系为材料,通过对其籽粒硬度相关基因的鉴定,明确黄淮麦区小麦新品系的籽粒硬度基因型分布规律,为小麦品质改良提供优异基因资源.[方法] 利用单籽粒谷物特性测定仪( SKCS)、PCR扩增、酶切以及DNA测序技术,对来自黄淮麦区109份小麦新品系的籽粒硬度表型、puroindoline基因型及其puroindoline b-2的不同等位变异类型进行了鉴定与分析.[结果] 黄淮麦区材料中硬质麦比例较高,为61.5％.混合型和软质麦比例较低,分别为15.6％和22.9％,硬度指数范围较宽,为3.2-82.6.在硬质麦的puroindoline 基因型检测中,发现有Pinb-D1b、Pinb-D1p和Pina-D1b共3种类型,其中,Pinb-D1b所占比例最高,为86.5％,Pinb-D1p和Pina-D1b分别为7.5％和6.0％.通过对puroindoline b-2变异检测,发现在调查的所有小麦材料中,D和A基因组上均含有Pinb-D2v1和Pinb-A2v4,其中,86份小麦品种(系)B基因组上的基因型为Pinb-B2v3,剩余的23份材料为Pinb-B2v2.通过对位于普通小麦B基因组puroindoline b-B2的2个基因型进行产量相关性状的分析,发现Pinb-B2v3变异的小麦品种(系)在穗粒数、单穗粒重、旗叶长和旗叶面积上均显著高于Pinb-B2v2变异类型的小麦品种(系),同时Pinb-B2v3变异类型小麦的千粒重、小穗数、粒长、粒宽和旗叶宽等性状也略高于Pinb-B2v2变异类型的小麦.[结论] 在黄淮麦区109份小麦新品系中,硬质麦比例较高,混合型和软质麦比例较低.硬质麦中,Pinb-D1b是最为常见的类型.在puroindoline b-2基因位点上,Pinb-B2v3变异类型小麦的产量相关性状略优于Pinb-B2v2变异类型小麦.%[Objective] Identification of hardness-related genes in wheat new lines or cultivars developed very recently in Huang-Huai Wheat Region of China could illustrate the distribution of hardness-related genes and provide important gene germplasm for improvement of wheat quality. [Method] A total of 109 wheat cultivars or advanced lines widely grown in Huang-huai wheat region were used to identify the phenotype of grain texture and genotype of puroindoline and puroindoline b-2 genes by the technologies of Single Kernel Characterization System (SKCS), PCR amplification with specific primers, restriction enzyme and DNA sequencing. [Result] The results showed that hard wheat with percentage of 61.5% was predominant whilepercentages of the mixed and soft wheats were only 15.6% and 22.9%, respectively, in wheat new lines surveyed. Based on SKCS results, grain hardness index of wheat surveyed ranged widely from 3.2 to 82.6. Three puroindoline alleles of Pinb-Dib, Pinb-Dlp and Pina-Dlb were detected in hard wheat surveyed. Of them, Pinb-Dib is the most prevalent with percentage of 86.5 %, while Pinb-Dlp and Pina-Dlb were only 7.5% and 6.0%, respectively. Furthermore, based on identification of puroindoline b-2 gene with gene-specific primers, all surveyed bread wheat genomes D and A contained Pinb-D2vl and Pinb-A2v4 variants, respectively. However, Pinb-B2v3 variant was only identified in the group B of 86 wheat cultivars or lines surveyed, and Pinb-B2v2 variant was found in the group B of remaining 23 cultivars or lines. The results of analysis of yield characters between Pinb-B2v2 and Pinb-B2v3 variants indicated that the averages of grain number, single grain weight, flag leaf length and flag leaf area of genotypes with Pinb-B2v3 variant were significantly higher than those of genotypes with Pinb-B2v2 variant. [ Conclusion ] Hard wheat was predominant in the wheat germplasms surveyed and Pinb-Dib was the most popular in hard wheat lines. In addition, the wheat with Pinb-B2v3 possessed relatively superior yield character to wheat with Pinb-B2v2.