小麦品种面筋强度、黄色素含量和PPO活性相关基因的分子检测

Molecular Characterization of Genes Associated with Gluten Strength,Yellow Pigment Content and PPO Activity in Chinese Wheat Cultivars

为给小麦品质育种筛选亲本材料,并进一步验证相关标记的有效性和实用性,利用5个小麦品质性状基因的分子标记[包括高分子量麦谷蛋白亚基(HMW-GS)Dx5和By8标记、1B/1R易位系特异性SCAR标记、位于7AL染色体与黄色素含量相关的八氢番茄红素合成酶(Phytoene synthase,PSY)基因Psy-A1的标记YP7A、位于2AL染色体的PPO活性基因Ppo-A1的标记PPO18]对157份小麦品种和优良新品系进行了基因等位变异检测。结果表明:(1)在所检测的小麦品种(系)中,Dx5、By8、1B/1R易位系、PSY和籽粒PPO活性基因等位变异存在一定差异。其中,含Dx5的材料29份,占18.5%,含By8和1B/1R易位系的材料分别为68和69份,占43.3%和43.9%,含低黄色素含量等位变异基因Psy-A1b的材料42份,占26.8%,含低PPO活性等位变异Ppo-A1b的等位变异材料78份,占49.7%;(2)157份材料中品质性状基因皆符合要求的只有一个品系(37042),聚合多个优良性状的品质改良工作急需加强;(3)本实验使用的标记均为基因特异性标记,重复性好、准确率高,可有效地应用于小麦品质改良的分子标记辅助选择。

Characterization of wheat quality genes is of great importance in quality improvement and molecular breeding. In the present study, 5 gene specific markers for HMW-GSDx5 andBy8 , 1B/1R translocation, Psy-A1 andPpo-A1 genes were used to detect the allelic variations at these loci in 157 Chinese wheat cultivars and advanced lines. The results indicated that different frequencies were detected for the allelic variations ofDx5 andBy8 , 1B/1R translocation, Psy-A1 andPpo-A1 genes in the wheat cultivars and advanced lines tested. The number of cultivars was 29, 68, 69, 42 and 78 with Dx5 , By8, 1B/1R, Psy-Alb related to low yellow pigment content andPpo-Alb associated with low PPO activity, and the frequencies accounted for 18.5%, 43.3%, 43.9%, 26.8% and 49.7%, respectively. Cultivars with all desired alleles for the five genes were present only in one genotype. It is vital to combine several quality genes into a cultivar. The markers employed in this study were all genespecific, with good repeatability and accuracy, and thus could be used as efficient molecular tools for marker-assisted selection （MAS） in wheat quality improvement programs.