西藏小麦高分子量谷蛋白亚基组成及其与蛋白质含量和沉淀值的关系

Composition of High Molecular Weight Glutenin Subunits in Tibet Wheat and Relationship with Protein Content and Sedimentation Value

为明确西藏小麦品种不同高分子量麦谷蛋白亚基(HMW-GS)对小麦品质的作用,对210份小麦品种的HMW-GS组成与蛋白质含量和沉淀值之间的关系进行了研究,结果表明,在Glu-A1位点上,亚基1、null和2*出现的频率依次为50.00%、34.76%和15.24%,各亚基对蛋白质含量和沉淀值的作用均为2*>1>null;在Glu-B1位点上,亚基7+8和7+9出现频率分别为45.71%和37.14%,远高于其它亚基出现的频率,各亚基对蛋白质含量的作用为7>14+15>17+18>6>7+9>22>7+8>6+8,对沉淀值的作用为17+18>7>14+15>7+9>7+8>6>6+8>22;在Glu-D1位点上,5+10与2+12出现频率分别为52.38%和47.14%,亚基12出现频率较低,各亚基对蛋白质含量的作用为5+10>12>2+12,对沉淀值的作用为5+10>2+12>12。HMW-GS所对应的蛋白质含量与沉淀值之间的相关系数为0.6535,达到了显著水平。以蛋白质含量为评价指标,较优的亚基组合有1/17+18/2+12、1/7/5+10、1/17+18/5+10、1/6+8/2+12、null/22/2+12、2*/17+18/5+10。以沉淀值为评价指标,较优的亚基组合有1/14+15/2+12、2*/17+18/5+10、2*/7/5+10。以蛋白质含量与沉淀值相结合为评价指标,本研究中HMW-GS的最优搭配为2*/17+18/5+10,其次为2*/7/5+10。HMW-GS组成类型所对应的蛋白质含量与沉淀值之间的相关系数为0.5571(P<0.05),达到了显著水平。

210 wheat varieties from Tibet were studied to investigate the relationships between protein contents,sedimentation value and high molecular weight （HMW） glutenin subunits. Three kinds of HMW-GS on Glu-Al were examined, which were 1, null and 2, and their frequency were 50.00%, 34.76% and 15.24%, respectively. The contributions of variation in Glu-A1 to the quality traits were determined as 2^＊ 〉l〉null. There were eight kinds of HMW-GS on Glu-B1, the frequency of 7＋8 and 7＋9 was 45.71%0 and 37.14%, respectively, which were higher than the other types. The contributions of variation in Glu-B1 to the protein contents were determined as 7〉14＋15〉17＋18〉6〉 7＋9〉22〉7＋8〉6＋8,to the sedimentation value were as 17＋18〉7〉14＋15〉7＋9〉7＋8〉6〉6＋8〉22. Three kinds of HMW-GS on Glu-D1 were examined, which were 5＋10, 2＋12 and 12, and their frequency were 52. 38%, 47. 14% and 0. 48%, respectively. The contribution of variation in Glu-D1 to the quality traits were determined as 5＋10〉12〉2＋12,to the sedimentation value were as 5＋10〉2＋12〉12. The protein contents corresponding to the HMW--GS appeared significant positive correlation with sedimentation value （r=0. 6535^＊ ）. Using the protein contents as the evaluation index, the more excellent subunit combinations were 1/17＋18/2＋12, 1/7/5＋10, 1/17＋18/5＋10, 1/6＋8/2＋12, nu11/22/2＋12, and 2^＊ /17＋18/5＋10. Using the sedimentation value as the evaluation index, the more excellent subunit combinations were 1/14＋15/2＋12, 2^＊ /17＋18/5＋10, 2^＊/17 ＋18/5＋10, 2^＊ /17＋18/5＋10, and 2^＊/7/5＋10. Using the sedimentation value and the protein contents together as the evaluation index, the best subunit combinations was 2^＊ /17＋18/5＋10, next one was 2^＊/7/5＋10. The protein contents corresponding to the subunit combinations appeared significant positive correlation with sedimentation value （r=0. 5571^＊ ）.