小麦体内次生物质对麦蚜的抗性作用研究

 采用蚜量比值法评价了 7个小麦品种 (系 )对麦长管蚜的抗性 ,并用紫外分光光度法测定了各品种 (系 )旗叶和穗部总酚和吲哚生物碱含量 ,并通过酶标仪法测定了来自不同抗级小麦穗部麦长管蚜体内的羧酸酯酶活性的差异 ,以此研究小麦体内次生物质含量的差异及其抗麦长管蚜的关系和抗性生化机制。结果表明 ,旗叶和穗部总酚和吲哚生物碱含量不同 ,表现出对麦长管蚜种群影响的差异。穗部吲哚生物碱含量与麦长管蚜蚜量比值之间呈极显著的负相关 ,相关指数R =- 0 .9896。而旗叶吲哚生物碱、旗叶总酚和穗部总酚含量与麦长管蚜蚜量比值的相关系数分别为 - 0 .6 82 6、- 0 .4 2 0 8和 - 0 .5 6 2 3,相关性均不显著。取食不同抗蚜品种 (系 )穗部的蚜虫羧酸酯酶活性与穗部吲哚生物碱含量呈显著相关性 (R =0 .96 4 6 ) ,而与穗部总酚含量相关性不显著 (R =0 .4 95 3)。与总酚含量相比 ,小麦穗部吲哚生物碱含量高低与小麦对麦长管蚜抗性关系更密切。

Effects of the Secondary Substances on Wheat Resistance to Sitobion avenae (F.)

The methods of aphid number ratio, UV, and kinetic measure were adopted to evaluate wheat resistance to Sitobion avenae (F.), total phenolic and indole alkaloid contents and the carboxylesterase activity of aphids from ears of different resistant varieties (lines) of wheat. And then, the different contents of the secondary substances in various wheat varieties (lines), the relationship between the total phenolic and indole alkaloid contents and wheat resistance to S. avenae (F.)and biochemical mechanism of wheat resistance to aphids were studied. The results indicated that there were different total phenolic and indole alkaloid contents in flag leaf and ear of wheat varieties (lines). The highly significant correlation was shown between indole alkaloid contents in wheat ear and aphid number ratio of S. avenae (R = -0.9896 ), and indole alkaloid contents of flag leaf, total phenolic contents of flag leaf, and total phenolic contents of ear of various wheat varieties (lines) were not significantly correlated to aphid number ratio of S. avenae. Carboxylesterae activity of S. avenae from ears of different resistant varieties (lines) of wheat was significantly correlated to indole alkaloid contents of wheat ears ( R =0.9646), and there was not significant correlation between CarE activity of S. avenae from ears of different resistant varieties (lines) of wheat and total phenolic contents of wheat ears ( R =0.4953).