五种寄主植物对甜菜夜蛾幼虫中肠蛋白酶活性的影响  

Effects of five different host plants on the midgut protease activities of the larva in Spodoptera exigua

作　　者：曾纪岚 孔祥东 董梓慧 仵均祥[1,2] 李怡萍[1,2] ZENG Ji-Lan;KONG Xiang-Dong;DONG Zi-Hui;WU Jun-Xiang;LI Yi-Ping(Key Laboratory of Plant Protection Resources and Pest Management, Northwest A & F University, Ministry of Education, Yangling 712100, Shaanxi Province,China;Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau, Ministry of Agriculture,Northwest A & F University, Yangling 712100, Shaanxi Province, China)

机构地区：[1]西北农林科技大学植保资源与病虫害治理教育部重点实验室,陕西杨凌712100 [2]西北农林科技大学农业部西北黄土高原作物有害生物综合治理重点实验室,陕西杨凌712100

出　　处：《环境昆虫学报》2019年第1期42-49,共8页Journal of Environmental Entomology

基　　金：国家自然科学基金(31871971; 31772503);陕西省农业科技创新与攻关项目(2016NY-058);国家重点研发计划资助(2017YFD0200900)

摘　　要：甜菜夜蛾Spodoptera exigua(Hübner)是重要的多食性、暴食性农业害虫之一。其寄主广泛,可危害禾谷类、甜菜、蔬菜、棉花等作物及杂草。昆虫中肠胰蛋白酶和胰凝乳蛋白酶在昆虫消化和生长发育中起重要的作用。本研究分别用辣椒、豇豆、玉米、甘蓝、反枝苋5种寄主植物饲喂甜菜夜蛾幼虫,利用酶专性底物分别测定了甜菜夜蛾幼虫中肠总蛋白酶活性、强碱性胰蛋白酶活性、弱碱性胰蛋白酶活性和胰凝乳蛋白酶活性。结果表明:甜菜夜蛾中肠总蛋白酶活性、强碱性胰蛋白酶活性、弱碱性胰蛋白酶活性以及胰凝乳蛋白酶活性在不同寄主植物之间存在显著差异,取食反枝苋甜菜夜蛾各中肠蛋白酶活性均高,取食甘蓝的各中肠蛋白酶活性均低,而取食玉米、豇豆、辣椒居中且活性差异不显著。取食同一寄主植物(反枝苋或甘蓝)不同龄期甜菜夜蛾幼虫的中肠蛋白酶活性也各不相同,随着龄期的增加,各中肠蛋白酶活性总体呈下降趋势,2龄幼虫的酶活性偏高,而5龄的酶活性显著低于其他龄期的酶活性。本研究明确了不同寄主植物对甜菜夜蛾幼虫中肠蛋白酶活性的影响,结果对明确甜菜夜蛾对寄主的适应性及对以中肠蛋白酶为靶标的害虫防治具有一定参考价值。Beet armyworm Spodoptera exigua (Hübner), is one of the important agricultural pests, which is polyphagous and predatory. Beet armyworm has wide host plants and could damage cereal crops, sugar beet, vegetables, cotton, crops and weeds, and so on. The alkaline trypsin activity and the chymotrypsin activity in insect play an essential role in the food digestion and growth of Lepidopteran insects. In this study, we determined the midgut protease activities from beet armyworms fed on five different host plants, Capsicum annuum , Vigna unguiculata , Zea mays , Brassica oleracea , Amaranthus retroflexus , by using the enzyme specific substrate. It was found that host plant had a significant effect on the midgut protease activities of the beet armyworm larva. Compared with the beet armyworms fed on other plants, there was a significant difference between the total midgut protease activity, high-alkaline trypsin activity, low-alkaline trypsin activity, and chymotrypsin activity in the larvae fed on B.oleracea or A.retroflexus . While, fed on C.annuum , V.unguiculata or Z.mays , the larvae had no significant difference in total midgut protease activity and low-alkaline trypsin activity. The midgut protease activities of beet armyworm in different instars were different. The activities of midgut proteases decreased with the increase of instar, and the 2 nd instar larvae showed more midgut protease activities than other instars. By contrast, the 5 th instar larvae had significantly lower midgut proteases activity than other instars. The results have certain valuable reference for clearing the adaptability of S.exigua to host and controlling insect pests with midgut protease as the target.

关 键 词：甜菜夜蛾 中肠 蛋白酶 活性 寄主植物 

分 类 号：Q963[生物学—昆虫学] S433[农业科学—农业昆虫与害虫防治]