蓟马取食对2种苜蓿抗虫酶活性的影响  

Effect of thrips feeding on activities of insect-resistant enzymes in two alfalfa species

作　　者：刘慧洁 特木尔布和 张志强 姜晓红 LIU Huijie;TEMUER Buhe;ZHANG Zhiqiang;JIANG Xiaohong(College of Grassland,Resources and Environment,Inner Mongolia Agricultural University,Hohhot,Inner Mongolia Autonomous Region 010000,China)

机构地区：[1]内蒙古农业大学草原与资源环境学院,内蒙古呼和浩特010000

出　　处：《西北农林科技大学学报（自然科学版）》2023年第7期12-18,26,共8页Journal of Northwest A&F University(Natural Science Edition)

基　　金：国家自然科学基金项目(32060388);内蒙古自治区高等学校科学研究项目(ZJZY20043)。

摘　　要：【目的】探究蓟马取食对2种苜蓿抗虫酶(多酚氧化酶(PPO)、过氧化物酶(POD)和苯丙氨酸解氨酶(PAL))活性的影响。【方法】以草原2号杂花苜蓿和草原4号紫花苜蓿品种为供试材料,在智能温室内分别对其进行牛角花齿蓟马接种和不接种处理,7 d后鉴定接种蓟马组苜蓿的虫情指数,并测定各处理苜蓿叶片的PPO、POD、PAL活性和总酚含量;以β-actin为内参基因,利用实时荧光定量PCR(qRT-PCR)分析PPO、POD、PAL基因的相对表达量。【结果】草原4号紫花苜蓿的虫情指数(0.418)显著低于草原2号杂花苜蓿(0.784);蓟马未取食处理的草原4号紫花苜蓿PPO和POD活性均显著高于草原2号杂花苜蓿(P<0.05),PAL活性无显著差异;蓟马取食处理2个苜蓿品种的PPO、POD、PAL酶活性均显著升高。蓟马取食处理2种苜蓿总酚含量均显著增加(P<0.05)。qRT-PCR分析发现,PAL、POD和PPO基因相对表达量的变化趋势与相应酶活性相同。【结论】草原4号紫花苜蓿抗虫性极强,抗虫酶基因表达量的变化趋势与相应酶活性的变化趋势一致;PPO、POD和PAL在组成型和诱导型苜蓿抗蓟马防御反应中具有重要作用。【Objective】This study explored the effects of thrips feeding on activities of insect resistant enzymes including polyphenol oxidase(PPO),peroxidase(POD)and phenylalanine aminolase(PAL)in two alfalfa species.【Method】The Caoyuan No.2 and Caoyuan No.4 varieties were treated with and without inoculation of Odontothrips loti in the smart greenhouse.After 7 days,the insect situation index of the thrips-inoculated group was determined,and PPO,POD and PAL activities and total phenolic content of alfalfa leaves in each treatment were measured.The relative expressions of PPO,POD and PAL genes were analyzed by real-time fluorescent quantitative PCR(qRT-PCR)usingβ-actin as the internal reference gene.【Result】The insect situation index of Caoyuan No.4(0.418)was significantly lower than that of Caoyuan No.2(0.784).Without thrips inoculation,PPO and POD activities of Caoyuan No.4 were significantly higher than those of Caoyuan No.2(P<0.05),while PAL showed no significantly differences among treatments.PPO,POD and PAL enzyme activities were significantly increased by thrips inoculation.The total phenolic content of Caoyuan No.2 and Caoyuan No.4 was also increased significantly by thrips feeding treatment(P<0.05).The qRT-PCR analysis revealed that the changes in relative expressions of PAL,POD and PPO genes were the same as the changes in corresponding enzyme activities.【Conclusion】Caoyuan No.4 had extremely strong resistance to insects.The gene expression of insect-resistant enzyme genes was consistent with the corresponding enzyme activities.PPO,POD and PAL had important roles in defense responses of inducible and constitutive alfalfa against thrips.

关 键 词：苜蓿 抗虫酶 牛角花齿蓟马 虫情指数 

分 类 号：S433.1[农业科学—农业昆虫与害虫防治]