【作者】 黄蓉；

【导师】 李俊凯；

【作者基本信息】 长江大学 ， 植物保护， 2023， 硕士

【摘要】 褐飞虱Brown rice planthopper（Nilaparvata lugens（St（?）l））是水稻上最重要害虫之一,广泛分布于我国和许多亚洲国家,具有突发性、暴发性的特点,且能远距离迁飞。化学防治是防治有害生物最有效的手段,但由于杀虫剂长期不合理使用,褐飞虱已经对34种具有杀虫活性的有效成分产生了不同程度抗性。烯啶虫胺和毒死蜱是水稻生产上防治褐飞虱的重要药剂,但褐飞虱对这两种杀虫剂已产生中等水平抗性,因此亟需评估褐飞虱对杀虫剂的抗性风险,鉴定响应烯啶虫胺和毒死蜱胁迫的解毒代谢基因。明确褐飞虱抗烯啶虫胺和毒死蜱的解毒代谢基因,揭示褐飞虱响应烯啶虫胺和毒死蜱胁迫的分子机制对杀虫剂的科学使用、害虫的有效防治、抗性发展的延缓和生态环境的保护有重要意义。基于此,本研究通过亚致死浓度(LC₁₀和LC₃₀)和致死浓度(LC₅₀和LC₇₀)烯啶虫胺和毒死蜱胁迫褐飞虱3龄若虫,探究褐飞虱体内3种解毒代谢酶活性以及5种解毒代谢基因的表达,拟揭示褐飞虱对两种杀虫剂胁迫的响应及分子机制,主要结论如下:1.烯啶虫胺对褐飞虱烯啶虫胺抗性品系LC₁₀、LC₃₀、LC₅₀、LC₇₀分别为129.24mg/L、259.75 mg/L、421.25 mg/L、683.15 mg/L;毒死蜱对其LC₁₀、LC₃₀、LC₅₀、LC₇₀分别为13.12 mg/L、18.96 mg/L、24.46 mg/L、31.56 mg/L。烯啶虫胺对褐飞虱敏感品系LC₁₀、LC₃₀、LC₅₀、LC₇₀分别为0.03 mg/L、1.46 mg/L、4.33 mg/L、12.83mg/L;毒死蜱对其LC₁₀、LC₃₀、LC₅₀、LC₇₀分别为0.64 mg/L、1.68 mg/L、3.30 mg/L、6.45 mg/L。2.亚致死浓度和致死浓度烯啶虫胺和毒死蜱分别处理褐飞虱烯啶虫胺抗性和敏感品系:发现烯啶虫胺和毒死蜱的LC₁₀胁迫诱导抗、敏褐飞虱体内酶活力提高;烯啶虫胺和毒死蜱LC₃₀、LC₅₀与LC₇₀胁迫,先诱导抗、敏褐飞虱体内P450s、Car Es、GSTs酶活力提高,再抑制P450s、Car Es、GSTs酶活力。4.通过q RT-PCR分析亚致死浓度和致死浓度烯啶虫胺和毒死蜱胁迫对褐飞虱P450s、Car Es、GSTs、UGTs、ABCs等解毒代谢基因表达的影响。其中P450s基因CYP4G76、CYP4CE1、CYP417A3、CYP6ER1、CYP6CS1,Car Es基因Nl Car E1、Nl Car E2、Nl Car E16、Nl Car E19、Nl Car E25、Nl Car E29,UGTs基因UGT-2A3、UGT-2B9、UGT-1-3,GSTs基因Nl GSTd2、Nl GSTe1、Nl GSTt1、Nl GSTo1、Nl GSTs3,以及ABCs基因Nl ABCB8、Nl ABCC3、Nl ABCD在褐飞虱烯啶虫胺抗、敏品系中能够被诱导上调表达,暗示这些基因可能与褐飞虱对烯啶虫胺和毒死蜱抗性有关。通过上述研究,揭示褐飞虱对烯啶虫胺和毒死蜱胁迫响应的分子机制,为合理科学使用烯啶虫胺和毒死蜱及深入开展研究褐飞虱解毒基因功能奠定理论础。更多还原

【Abstract】 The brown planthopper（BPH）,Nilaparvata lugens（St（?）l）（Hemiptera:Delphacidae）is one of the most important pests on rice,widely distributed in China and many Asian countries,with sudden and violent characteristics,and could migrate long distances.At present,the control of brown planthopper still mainly relies on chemical insecticides.However,field populations of N.lugens have developed varying levels of resistance to34 active ingredients with insecticidal activity due to the long-term irrational use of insecticides.Nitenpyram and chlorpyrifos are important insecticides for controlling N.lugens in rice production,but N.lugens has developed moderate levels of resistance to both insecticides.Therefore,there is an urgent need to assess the risk of resistance to insecticides in N.lugens and to identify detoxification metabolism genes in response to nitenpyram and chlorpyrifos stress.It is important to identify the detoxification metabolism genes of N.lugens against nitenpyram and chlorpyrifos.And to reveal the molecular mechanism of response to nitenpyram and chlorpyrifos stress in brown planthopper for scientific use of insecticides,effective control of insect pests,delay of resistance development and protection of ecological environment.Based on this study,we investigated the activities of three detoxification metabolism enzymes and the expression of genes of five detoxification metabolism enzymes in the N.lugens treated with sublethal and lethal concentrations of nitenpyram and chlorpyrifos to reveal the response of N.lugens to the two insecticide stresses and the molecular mechanisms.The main results are listed as follows:1.The LC₁₀,LC₃₀,LC₅₀ and LC₇₀ of nitenpyram to nitenpyram-resistant strain of N.lugens were 129.24 mg/L,259.75 mg/L,421.25 mg/L and 683.15 mg/L,respectively;and the LC₁₀,LC₃₀,LC₅₀ and LC₇₀ of chlorpyrifos to nitenpyram-resistant strain of N.lugens were 13.12 mg/L,18.96 mg/L,24.46 mg/L and 31.56 mg/L,respectively.The LC₁₀,LC₃₀,LC₅₀,and LC₇₀ of nitenpyram to nitenpyram-susceptible strain of N.lugens were 0.03mg/L,1.46 mg/L,4.33 mg/L,and 12.83 mg/L,respectively;the LC₁₀,LC₃₀,LC₅₀,and LC₇₀ for chlorpyrifos in nitenpyram-susceptible strain of N.lugens were 0.64 mg/L,1.68mg/L,3.30 mg/L and 6.45 mg/L,respectively.2.The nitenpyram-resistant and susceptible strains of N.lugens were treated by sublethal and lethal concentrations of nitenpyram and chlorpyrifos,respectively.It was found that an increase in enzyme activity in resistant and susceptible brown planthopper was induced treated with LC₁₀ of nitenpyram and chlorpyrifos.The stress of LC₃₀,LC₅₀and LC₇₀ with nitenpyram and chlorpyrifos induced an increase in enzyme activity of P450s,Car Es and GSTs in resistant and susceptible N.lugens first,and then the enzymatic activity of P450s,Car Es and GSTs was inhibited.3.The expression of detoxification metabolic genes such as P450s,Car Es,GSTs,UGTs and ABCs in brown planthopper were analyzed by q RT-PCR when they were treated with sublethal and lethal concentrations of nitenpyram and chlorpyrifos.The result showed that P450 genes CYP4G76,CYP4CE1,CYP417A3,CYP6ER1,CYP6CS1;Car E genes Nl Car E1,Nl Car E2,Nl Car E16,Nl Car E19,Nl Car E25,Nl Car E29;UGT genes UGT-2A3,UGT-2B9,UGT-1-3;GST genes Nl GSTd2,Nl GSTe1,Nl GSTt1,Nl GSTo1,Nl GSTs3;and ABC transporter protein genes Nl ABCB8,Nl ABCC3,Nl ABCD could be induced up-regulated expression in N.lugens nitenpyram-resistant and susceptible strains,suggesting that the expression of these genes may be associated with N.lugens resistance to nitenpyram and chlorpyrifos.Through the above study,we will reveal the molecular mechanism of the response of N.lugens to the stress of nitenpyram and chlorpyrifos,and lay the theoretical foundation for the rational and scientific use of nitenpyram and chlorpyrifos and the in-depth research on the function of the detoxification genes of N.lugens.更多还原