小麦Pod-A1、Pod-D1和Pod-2D位点等位变异对籽粒过氧化物酶活性的遗传效应分析OA

Peroxidase(POD)activity in wheat grains strongly influences processing quality and the color of wheat-based products,and is therefore an important target for quality improvement.In this study,151 wheat varieties(lines)from domestic and international sources were used to systematically characterize allelic variation at the Pod-A1,Pod-D1,and Pod-2D loci using molecular markers.Together with multi-year,multi-location measurements of grain POD activity,we evaluated the effects of individual alleles and their combinations on POD activity.Grain POD activity showed substantial genetic variation,with a mean of 674.39 U g-1 min-1,a range of 431.30-954.81 U g-1 min-1,and a coefficient of variation of 15.52%.Environ-ment,genotype,and their interaction all had highly significant effects on POD activity(P<0.01).All three loci significantly affected grain POD activity,and the favorable alleles were Pod-A1b,Pod-D1b,and Pod-2D-GG,respectively.In total,12 alle-lic combinations were identified and classified into high-,medium-,and low-activity combination types based on grain POD activity.POD activity differed significantly among the three types(P<0.05),whereas no significant differences were detected within each type.The genetic effects of the three loci on grain POD activity followed the order Pod-2D>Pod-A1>Pod-D1.Grain POD activity increased significantly with the number of favorable alleles(R2=0.9681,P<0.05);varieties(lines)pyramiding 2-3 favorable alleles had significantly higher POD activity than those carrying 0-1 favorable allele(P<0.05).Significant regional differences were observed in POD activity,allelic variation,and allelic-combination frequencies.Nine varieties,including Liangxing 66,Lankao 24,and Jimai 22,were identified as carrying all three favorable alleles and exhibi-ting POD activity above 800 U g-1 min-1.These findings provide a theoretical basis and germplasm resources for molecular marker-assisted breeding to optimize wheat grain POD activity.