小麦多酚氧化酶活性的品种间差异及其遗传分析研究进展

Advance in variations of polyphenol oxidase(PPO) activity and genetic properties in wheat varieties

PPO活性高低是影响面条等食品色泽及其品质的关键因素,遗传改良是降低PPO活性的有效途径。采用全麦粉法测定了131份小麦品种,其两年PPO活性相关极显著,r=0.839;扬麦158×淮麦18组合376个F2单株和F3株系PPO活性呈高度相关,r=0.727;用邻苯二酚代替多巴,检测了(烟农19×安农0016)F3代的117个株系,2种方法测定的PPO活性相关系数高达0.907。对上述杂交组合后代群体的遗传分析表明,PPO活性主要受两对主基因控制。根据GenBank(AY515506)设计引物,其中STS01在高低PPO活性的材料中产生了差异。131份小麦品种中有76个品种扩增出560 bp的目标片段,PPO活性均值为221.44,55个品种没有扩增产物,PPO活性均值为309.98,两者差异达到1%显著水平。将STS01与中国农业科学院作物所开发的分子标记PPO18进行协同效应分析表明,两者为独立遗传的小麦籽粒PPO活性STS分子标记。PPO活性的检测表明,我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。2年试验筛选出渝02321、宁麦9号、02P157、02Y151、34-th195、宁0076、鄂麦19等12个低PPO活性的品种资源。

Polyphenol oxidase （PPO） in grain is regarded as a major factor resulting in time-dependent darkening of wheat end products, particularly for Asian noodles. In this study,a wholemeal assay for PPO activity was used and the results were as follows：coefficient index between two crop seasons（2004 and 2005）was 0. 839 in PPO activity of 131 wheat varieties,and that between F2 single plants and F3 lines was 0. 727 in the combination Yangmai 158×Huaimai 18 ,both were highly significant. PPO activity tested by catechol as substrate was significant correlated with that by L-DOPA （r = 0. 907） in the progenies from Yannong19×Annong0016. The genetic analysis indicated that PPO activity of the combinations was controlled by two major genes. Based on the cDNA sequence （ GenBank Accession Number：AY515506） ,8 pairs of primers were designed using the software＇ Primer premier 5.0＇. One of the markers designated as STS01 can amplify a 560 bp fragment in cultivars with low PPO activity, while no PCR fragment was detected in cultivars with high PPO activity. To understand the relationship between STS01 and PPO18, which was developed by Institute of Crop Science, Chinese Academy of Agricultural Science, allelic variations in both STS01 （L1 and H1 ） and PPO18 （L2 and H2） loci were detected. The results suggested that two markers were genetically independent and the allelic variation of two PPO genes could explain 63. 06% of phenotypic variance for PPO activity of 131 Chinese wheat cultivars through two crop seasons. The tests for PPO activity demonstrated that the variations were highly significant in wheat varieties, and there was great potential for the genetic improvement. The varieties with low PPO activity included Yu02321, Ningmai9,02P157,02Y151,34-th195, Ning0076, Emai19, et al.