小麦低多酚氧化酶活性品种资源的筛选

为了研究中国小麦品种资源多酚氧化酶(PPO)活性的变异,并筛选稳定的低PPO活性种质资源,于2003～2004和2004～2005年度分别种植131份小麦品种及资源,采用全麦粉法测定了其PPO活性.结果表明,其两年PPO活性相关极显著,r=0.839.根据STS01和PPO18两个标记位点共同出现的变异情况,将供试品种分为4种基因组合类型,即H1H2、L1H2、H1L2、L1L2.检测结果表明,中国大面积种植的一些小麦品种PPO活性差异很大,说明遗传改良具有很大的潜力.最终筛选出了渝02321、宁麦9号、02P157、02Y151、34-th195、宁0076、鄂麦19等23个L1L2型低PPO活性品种资源.

Screening of Wheat Varieties with Low Polyphenol Oxidase Activity

Polyphenol oxidase(PPO) in grain is regarded as a major factor resulting in time-dependent darkening of wheat end-products,particularly for Asian noodles.Genetic improvememt is an efficient way to reduce PPO activity.To understand the variations of wheat PPO activities in wheat varieties from China,and to select wheat varieties with steady and low PPO activities,131 wheat varieties were planted in the year of 2003~2004 and 2004~2005 respectively,a whole-meal assay for PPO activity was used and the results were as follows:correlation coefficient between two crop seasons(2003~2004 and 2004~2005)was 0.839 in PPO activity of 131 wheat varieties.Two PCR markers(PPO18 and STS01) were used for detecting allelic variations of PPO genes in chromosome 2A and chromosome 2D,respectively.H1 and L1 at the PPO18 locus,H2 and L2 at STS01 locus,were considered to be related with high and low PPO activity,respectively.According to PPO genotype,131 wheat varieties can be classified into four types,including H1H2,L1H2,H1L2,L1L2.The results showed that higher variations of PPO activity were observed in some wheat cultivars commonly planted in China.The varieties with low PPO activity included Yu 02321,Ningmai 9,02P157,02Y151,34-th195,Ning 0076,Emai 19 and their genotypes all were L1L2.