中文摘要：

分别以α-NA、α-NB为底物测定了经狗尾草、水稻、小麦三种不同寄主植物饲喂1 d、3 d和5 d后中华稻蝗四龄若虫雌、雄虫的酯酶比活力.结果表明,不同寄主植物对中华稻蝗四龄若虫的酯酶有诱导作用,且水稻组酯酶比活性显著高于狗尾草组和小麦组.以α-NA为底物测定酯酶活性,喂食1 d后,水稻组雌、雄虫酯酶比活力分别是狗尾草组、小麦组的1.35、2.00倍和1.44、1.63倍.喂食3 d后,水稻组雌、雄虫酯酶比活力分别是狗尾草组、小麦组的1.40、1.67倍和1.62、1.43倍.喂食5 d后,雌虫酯酶比活力水稻组分别是狗尾草组、小麦组的1.63、2.00倍,雄虫酯酶比活力水稻组分别是狗尾草组、小麦组的2.00、1.71倍.上述结果可能与不同寄主植物所含的次生代谢物质对酯酶的诱导作用有关,且在三种寄主植物中水稻的诱导作用最强.饲喂同一寄主植物1 d、3 d和5 d后,害虫体内酯酶比活性没有显著性差异,但总体趋势是饲喂1d后的酯酶比活性稍高于饲喂3 d和5 d后的,这可能是害虫在饥饿后进食的应激反应所造成的.研究结果还表明不同寄主植物诱导后中华稻蝗体内酯酶对不同底物的水解能力有所差异.

英文摘要：

The specific activity of esterase （EST） hydrolyzing the two substrates （α-NA and α-NB） in the fourth-instar nymph of Oxya chinensis fed on three host plants （Setaria viridis,Triticum aestivum and Oryza sativa） for 1 d,3 d and 5 d were studied. The results showed that there were significant difference （p〈0. 05） in EST activity among the three host plants. O. chinensis fed on rice had the highest EST activity. When used α-NA as substrate,fed on different host plants for 1 d,the EST activity of O. chinensis fed on grass and wheat in females and males was 0.74,0.5 and 0.69,0.62 times compared to that of O. chinensis fed on rice,respectively. Fed different host plants for 3 d,the EST activity of O. chinensis fed on grass and wheat in females and males was 0.71,0.6 and 0.62,0.7 times compared to that of O. chinensis fed on rice,respectively. Fed different host plants for 5 d,the EST activity of O. chinensis fed on grass and wheat in females and males was 0.61,0.5 and 0.5,0.58 times compared to that of O. chinensis fed on rice, respectively. It may be inferred that different allelochemicals in different plants have various induction on EST activity of O. chinensis and rice had the highest induction ability on EST activity. O. chinensis fed on the same host plant for different days,there was no significant difference （p〉0.05） in the EST activity, but there was an obvious trend,namely,the EST activity of Oxya chinensis fed on host plants for 1 d was a little higher than those for 3 d and 5 d. Based on this phenomenon,it suggested that O. chinensis had a contingency response when given enough foods after the stress of hunger. The results also showed that the EST activity of O. chinensis fed on different host plants have different hydrolyzing ability for different substrates.