【作者】 曹明章；

【导师】 沈晋良；

【作者基本信息】 南京农业大学 ， 农药学， 2004， 博士

【摘要】 二化螟[Chilo suppressalis(Walker)]是水稻的重要害虫之一，常年在长江流域发生较重。上世纪90年代以来，二化螟发生危害再次呈加重趋势，部分地区暴发危害难于防治，对水稻的高产稳产构成严重威胁。 二化螟抗药性增强是其危害加重的重要原因之一。杀虫单、三唑磷、氟虫腈及阿维菌素等是我国近年来防治二化螟使用较多的四种代表性杀虫剂，它们作用机理各异，使用历史也不同。浙江、江苏、安徽、江西等是水稻二化螟发生危害较重的省份。本项研究针对这些地区二化螟代表种群对上述四种药剂的抗性，进行抗性检(监)测，弄清抗性现状；通过药剂筛选估计抗性现实遗传力，预测抗性发展速度；采用毒力回归线法分析三唑磷和杀虫单抗性的遗传方式；测定抗性种群对不同类型杀虫剂的交互抗性或敏感性；并对抗性与生化代谢机制的关系进行初步研究。 以黑龙江二化螟种群(HLJ)为相对敏感品系，采用4龄幼虫点滴法测定了14种药剂的毒力基线，这些药剂对HLJ相对敏感种群的触杀毒力顺序为：阿维菌素＞高效氯氟氰菊酯，氟虫腈＞辛硫磷，三唑磷，毒死蜱，杀螟硫磷＞虫酰肼＞二嗪磷，灭多成，敌百虫＞硫丹，杀虫单，乙酰甲胺磷。 2001-2003年对浙、苏、皖、赣四省的二化螟不同种群进行了抗药性检(监)测，结果表明：(1)氟虫腈防治二化螟在很多地方至今还不超过5年，且因其价格高，每年的用量不大，但在二化螟发生危害严重的浙江省温州、台州地区使用较早，每年使用次数也较多；监测的大多数种群对氟虫腈保持敏感，与敏感基线相比的抗性倍数小于3倍；2002年首次发现浙江瑞安种群(ZJRA)对氟虫腈有8.7倍低水平抗性，2003年跟踪监测证实了该种群对氟虫腈有抗性，而且地理分布更南的两个邻近县(平阳和苍南)的二化螟(ZJPY、ZJCN)对氟虫腈也有抗性，三种群的抗性倍数分别为11.4、13.0和15.0倍，达中等水平抗性。(2)阿维菌素是一种具有杀虫杀螨作用的抗生素，主要以混剂形式用于防治二化螟，使用时间也不长：所有种群对其抗性倍数均小于3，未产生抗性。(3)三唑磷是对二化螟活性高的一种杂环有机磷杀虫剂，上世纪90年代初首先在浙江温台地区推广防治二化螟等水稻害虫，近1、2年逐渐取代杀虫单(双)而成为人面积防治二化螟的主导药刑；监测发现浙江瑞安(ZJRA)、平阳(ZJPY)和苍南(ZJCN)三种群为高抗～极高抗，浙江温州瓯海种群(ZJWZ)为中抗，江苏苏南的常熟(JSCS)、锡山(XS)、金坛(JSJT)、武进(WJ)等种群为低水平抗性，江苏苏北(JSLYG、JSXY、SY、CZ等)、江西宜半(JXYF)和安徽太湖(AHTH)种群为敏感。(4)杀虫单属沙蚕毒素类杀虫刑，是上世纪80年代后防治二化螟使用最多的药剂，监测的几乎所有种群对其均有不同程度抗性，其中瑞安(ZJRA)、平阳(ZJPY)、苍南(ZJCN)和宜丰(JXYF)四种群达高水平抗性(57.6～113.7倍)，温州(ZJWZ)、金坛(JSJT)、常熟(JSCS)和太湖(AHTH)等4个种群为中等水平抗性(110-29.7倍)，连云港(JSLYG)和新洋农场(JSXY)等苏北种群对杀虫单为低水平抗性(5.0～7.8倍)，只有个别种群如江苏灌云处于敏感度下降阶段。‘化螟抗药性监测、对三哇磷和杀虫单抗性遗传分析及对氟虫睛抗性风险评估 2002和2003年重复监测浙江瑞安(ZJRA)和安徽太湖(AHTH〕两种群抗药性，结果显示，同一地点同一代次相邻年份测得的杭性水平变化不大，杭性倍数95%置信区间多数有重叠. 在室内不接触药剂条件下，对浙江苍南种群(ZJCN)的杭药性稳定性进行了观察.结菜表明，对杀虫单、三哇磷和氛虫睛的抗性稳定性不同。对杀虫单抗性在前3代下降明显，之后直至F7代稳定在一定水平;而氟虫睛和三哇磷LDS。在F:一Fs下降缓慢、幅度小。 以浙江平阳种群(ZJPY)为起始种群，用2.56一6.72，g/头三吐磷点滴4龄幼虫进行室内筛选。连续筛选6代后的品系(PY一t)，对三吐磷杭性水平达1636.1倍，比筛选前增加了2.59倍;根据筛选结果佑算的杭性现实遗传力(矛)为0.4835. 用氟虫睛对浙江苍南种群(ZJCN)进行了连续7代筛选，筛选剂量为0.0128-0.02陀/头。与敏感品系相比，筛选品系(CN一FR)对氛虫睛抗性水平从巧倍提高到23.3倍，抗性上升0.55倍，hZ为0.3388. 以浙江温州种群(ZJWZ)为起始种群，室内累计饲养繁殖24代，期间用杀虫-单筛选19代，得杭性品系WZ一m，对杀虫单杭性达774.5倍，比筛选前上升25.0倍;根据前期(F3一F:)连续6代筛选估计的hZ(0.2303)显著低于后期(F，9-F23)连续筛选5代的hZ(1 .2055)，而中间(F。一F::)20代中有4代未筛选，hZ也最小(0.0243). 以三哇磷筛选后的RA一t和PY一t为抗性品系，分别与室内敏感品系进行正反杂交、回交及自交，分析二化螟对三吐磷杭性的遗传方式.实验显示，PY一t品系与敏感品系正反交F.代的三哇磷LDS。差异不显著、显性度(D)为0.62和0.68，合并计算的F:显性度为0.65，抗性属不完全显性、常染色体遗传;正反交F，分别与敏感亲本回交，回交后代的三吐磷LD一p曲线在机率值5附近有明显平坡，除两端外，与单个主基因假设的期望曲线基本吻合，且卡方(才)测验显示，在测定的11个剂量中，有6(BC)或7(BC)个与单个主基因控制的假设相符，但在两端、尤其是低剂量端，实际反应与单基因假设不?更多还原

【Abstract】 Striped stem borer, Chilo suppressalis (Walker), is one of major insect pests of rice in China, especially in the valley of Changjiang River. In recent 10 years, population of this pest and its damage to rice increased dramatically, severely threatening the high and stable yields of rice. For a long time, populations of C. suppressalis are controlled mainly by the use of chemical insecticides. Insecticide resistance in C. suppressalis was one of the main factors for its infestation increase.Monosultap, triazophos, fipronil and abamectin are four major insecticides used to control C. suppressalis in recent years. They are different from each other in mode of action and with distinct application background in rice field. Zhejiang, Jiangsu, Anhui and Jiangxi are four provinces where infestation and damage of C. suppressalis are most serious. The aims of present study include: to investigate current situation of resistance in C. suppressalis to the above four insecticides in the four provinces; to estimate realized heritability of resistance against triazophos, monosultap and fipronil through selection so as to predict resistance development rate; to analyze mode of inheritance of triazophos and monosultap resistance by means of log dose-mortality probit line analysis; to determine cross resistance and susceptibility of selected resistant strains to various types of insecticides; and, to gain preliminary information on the possible underlying mechanism(s) of insecticide resistance in C. suppressalis.A field population (HLJ) was collected from Heilongjiang province, where little insecticide was used to control C. suppressalis before 1998, and used as reference susceptible strain for resistance determination. Baseline toxicities of 14 insecticides to 4th instar larvae of HLJ population were assayed using topical application method. The toxicity of these insecticides was in the order of abamectin > lambda-cyhalothrin, fipronil > phoxim,triazophos, chlorpyrifos, fenitrothion > tebufenozide > diazinon, methomyl, trichlorfon > endosulfan, monosultap, and acephate.During 2001-2003, insecticide resistance was determined with populations from four provinces-Zhejiang, Jiangsu, Anhui and Jiangxi. Results showed:(1) Fipronil. Fipronil is a more recently introduced insecticide for controlling of C. suppressalis and other rice pest insects in most places. But in Wenzhou and Taizhou area, southeast of Zhejiang province, it had been applied extensively to control heavy infestation of C. suppressalis since around 1997, two or three years earlier than other places and with more application times each year. Most populations examined remained susceptible (resistance ratios < 3-fold). However, in 2002, for the first time, a population (ZJRA) from Ruian, Zhejiang was found to have 8.7-fold resistance. The resistance was confirmed in the following year. In addition, populations from two adjacent counties --Pingyang (ZJPY) and Cangnan (ZJCN), to the south of Ruian, were also resistant to fipronil. Resistance ratios for these three populations in 2003 were 11.4- (ZJRA), 13.0- (ZJPY) and 15.0-fold (ZJCN).(2) Abamectin, an antibiotic with powerful insecticidal and miticidal action, had been used on rice to control C. suppressalis mainly in form of mixtures. Susceptibility to abamectin had not decreased significantly in any population detected (all resistance ratios < 3-fold).(3) Triazophos, an organophosphate, was first introduced to control monosultap-resistant C. suppressalis in early-1990s in Zhejiang. It has gradually replaced monosultap (and bisultap) becoming the preferred insecticide for controlling of C. suppressalis in large areas recent years. Resistance monitoring revealed that three populations ZJRA, ZJPY and ZJCN from Zhejiang had high or extremely high resistance; that ZJWZ population from Ouhai (a suburb district of Wenzhou, Zhejiang) had moderate resistance (18.2-fold); that four populations from Changshu (JSCS), Xishan (XS), Jintan (JSJT) and Wujin (WJ), all in south Jiangsu, had low level of resistance (6.0- to 9.7-f更多还原