热胁迫下春小麦品种产量性状耐热性差异及相关分析

Correlation Analysis and Difference in Heat Tolerance with Yield Trait of Different Spring Wheat under Heat Stress

以宁夏灌区大面积种植的小麦品种（系）为供试材料（35个）,在小麦灌浆后期通过人工升温鉴定耐热性,结果表明,不同基因型热胁迫处理与正常环境相比千粒重降低幅度在1.2%-30.2%间,穗粒重降低幅度在0.5%-40.0%间。不同基因型间的耐热性存在较大差异,千粒重感热指数在0.09-2.86间,有3个材料千粒重感热指数S〈0.2,表现较强的耐热性。耐热材料（S〈1,n=17）的平均千粒重、穗粒重、穗粒数较热敏感材料（S〉1,n=18）分别低0.43g、0.22g和2.19粒。晚熟材料较中熟材料的丰产性好、耐热性差。相关分析表明,千粒重感热指数与热胁迫下的千粒重呈极显著负相关。千粒重感热指数与穗粒重感热指数、千粒重几何平均产量与穗粒重几何平均产量间均呈极显著正相关。

35 varieties （lines） of wheat which were planted in irrigation area of Ningxia were identified heat tolerance by manual temperature rise in late filing. The results showed 1 000-kernel weight of different wheat genotypes were reduced from 1.2%to 30.2% under heat stress to compare with normal environment, Kernel weight per spike of wheat varieties were reduced from 0.5% to 40 %. There is significant difference of heat tolerance in different wheat genotypes, the range of heat susceptibility index of 1000-kernel weight is from 0.09 to 2.86, three wheat materials showed higher heat tolerance. Mean of 1000-grain weight, kernel weight per spike and kernels of per spike of heat tolerance wheat materials（S〈1 ,n=17） are lower separately by 0.43 g,0.22 g and 2.19 kernels than heat susceptibility wheat varieties（S〉1, n= 18）. Serotinous materials are better in yield trait and worse in heat tolerance. Correlation analysis of result suggested that negative correlation was highly significant between heat susceptibility indexes of 1000-grain weight with 1000-grain weight under heat stress. Between susceptibility heat index of 1000-grain weight and spike-grain weight,and between geometric mean yield per plant of 1000-grain weight and spike-grain weight all showed significant positive correlation.