GABA_(B)受体介导草地贪夜蛾幼虫对甜味和苦味物质的取食选择  

GABA_(B)receptor mediates the feeding preference of Spodoptera frugiperda(Lepidoptera:Noctuidae)larvae to sweet and bitter substances

作　　者：刘永冲 孙龙龙 霍昳陶 牛林 王豪杰 张元臣 闫凤鸣[1] 刘龙 马英[3] 汤清波[1] LIU Yong-Chong;SUN Long-Long;HUO Yi-Tao;NIU Lin;WANG Hao-Jie;ZHANG Yuan-Chen;YAN Feng-Ming;LIU Long;MA Ying;TANG Qing-Bo(Henan International Laboratory for Green Pest Control,Institute of Chemical Ecology,College of Plant Protection,Henan Agricultural University,Zhengzhou 4500046,China;Taihang Mountain Forest Pests Observation and Research Station of Henan Province,Anyang 456582,China;National Engineering Research Center for Wheat,College of Agronomy,Henan Agricultural University,Zhengzhou 450046,China)

机构地区：[1]河南农业大学植物保护学院,化学生态学研究所,河南省害虫绿色防控国际联合实验室,郑州450046 [2]河南省太行山林业有害生物野外科学观测研究站,安阳456582 [3]河南农业大学农学院,国家小麦技术创新中心(筹),郑州450046

出　　处：《昆虫学报》2024年第11期1451-1460,共10页Acta Entomologica Sinica

基　　金：河南省自然科学基金重点科学基金项目(232300421110);河南省科技攻关项目(242102111091);国家自然科学基金项目(31672367);河南省太行山林业有害生物野外科学观测研究站开放课题(THFP202306)。

摘　　要：【目的】本研究旨在探究昆虫重要的抑制性神经递质γ-氨基丁酸(γ-aminobutyric acid,GABA)B型受体(GABA_(B)receptor)在介导草地贪夜蛾Spodoptera frugiperda幼虫对甜味物质和苦味物质的取食选择中的作用。【方法】利用RT-qPCR测定GABA_(B)受体基因在不同龄期(1-6龄)第2天草地贪夜蛾幼虫以及在5龄第2天幼虫不同组织(头、表皮、中肠、脂肪体和血淋巴)中的表达量;饲喂草地贪夜蛾5龄幼虫ds GABA_(B)R沉默GABA_(B)受体基因,向5龄幼虫注射GABA_(B)受体拮抗剂,利用叶碟法分别测定ds GABA_(B)R和GABA_(B)受体拮抗剂处理后5龄幼虫对甜味物质蔗糖和苦味物质黑芥子苷的取食选择指数以及对玉米叶片的摄食面积。【结果】GABA_(B)受体基因在草地贪夜蛾1龄幼虫中的表达量显著高于其他龄期幼虫,在5龄幼虫脂肪体中的表达量显著高于其他组织中的。5龄幼虫饲喂dsGABA_(B)R后对玉米叶片的摄食面积显著低于对照幼虫,且不再显著趋向取食蔗糖,但是对苦味物质黑芥子苷依然表现为拒食反应。5龄幼虫血淋巴中注射GABA_(B)受体拮抗剂后对玉米叶片的摄食面积也显著低于对照幼虫;不同于对照幼虫显著趋向取食蔗糖的行为,注射GABA_(B)受体拮抗剂的5龄幼虫对蔗糖表现为显著拒食行为;但是,5龄幼虫对苦味物质黑芥子苷的拒食趋势没有显著改变。【结论】GABA_(B)受体能够显著影响草地贪夜蛾幼虫的摄食量,以及改变幼虫对甜味物质的趋向取食,但是对幼虫拒食黑芥子苷的趋势没有显著影响。本研究结果有助于我们理解昆虫取食行为的调控机制。【Aim】The aim of this study is to investigate the role of the important inhibitory neurotransmitterγ-aminobutyric acid(GABA)B-type(GABA_(B))receptor in modulating the feeding preference of the fall armyworm,Spodoptera frugiperda larvae in response to sweet and bitter substances.【Methods】RT-qPCR was used to identify the expression levels of GABA_(B)receptor gene in larvae(day-21st instar to day-26th instar)and different tissues(head,cuticle,midgut,fat body and hemolymph)of the day-25th instar larvae of S.frugiperda.The GABA_(B)receptor gene was silenced by feeding the 5th instar larvae of S.frugiperda with ds GABA_(B)R.The GABA_(B)receptor antagonist was injected into the 5th instar larvae.Using the leaf disc method,the feeding preference indexes for sucrose(sweet substance)and sinigrin(bitter substance),as well as the feeding area on maize leaves of the 5th instar larvae after the treatments with ds GABA_(B)R and GABA_(B)receptor antagonist were detected,respectively.【Results】The expression level of GABA_(B)receptor gene in the 1st instar larvae was significant higher than those in the other instar larvae of S.frugiperda.The expression level of GABA_(B)receptor gene in the fat body of the 5th instar larvae of S.frugiperda was significantly higher than those in the other tissues.After ds GABA_(B)R feeding treatment,the feeding area on maize leaves of the 5th instar larvae significantly decreased as compared with that of the control larvae,the 5th instar larvae didn’t significantly prefer to feed sucrose and exhibited aversive feeding behaviors to the bitter substance sinigrin.After injecting GABA_(B)receptor antagonist into the hemolymph,the feeding area on maize leaves of the 5th instar larvae also decreased significantly as compared to that of the control larvae.Unlike the control larva significantly preferred to feed sucrose,the 5th instar larvae injected with GABA_(B)receptor antagonist showed obviously aversive feeding behaviors to sucrose.While both control larvae and larvae injected with GABA_

关 键 词：草地贪夜蛾 GABA_(B)受体 RNAI 拮抗剂 摄食量 取食选择 

分 类 号：S435.622[农业科学—农业昆虫与害虫防治]