棉铃虫对拟除虫菊酯抗性稳定性研究

研究棉铃虫Helicoverpa armigera (Hubner)对三种拟除虫菊醌（氰戊菊酯、溴氰菊酯、功夫菊酯)的抗性稳定性及敏感性恢复表明,即使棉铃虫对氰戊菊酯的抗性达到3166.3倍以上,抗性仍不稳定,经14代室内饲养后抗性下降为61.4倍;对一系列田间抗性种群的抗性稳定性研究后发现,棉铃虫对这三种拟除虫菊酯的抗性不稳定,在没有杀虫剂选择的情况下,开始几代抗性下降较快,当下降到一定水平(2～9倍)后,抗性比较稳定,很难完全恢复对拟除虫菊酯的敏感性。     

家蝇对DDT和拟除虫菊酯的重要抗性机制——中枢神经系统的不敏感性

本文以电生理技术研究了四个品系的家蝇Musca domestica vicina Macq.中枢神经系统(CNS)对DDT、二氯苯醚菊酯和澳氰菊酯的敏感性,结果表明:三种抗性家蝇,DDT高抗品系(DDT-R)、二氯苯醚菊酯高抗品系(2C1-R)和溴氰菊酯高抗品系(Dec-R)的中枢神经系统(CNS)对三种杀虫剂的敏感性与敏感家蝇相比均明显降低,而且,GNS的不敏感性随杀虫剂LD₅₀的升高有逐渐上升的趋势.我们认为,CNS不敏感性是家蝇对DDT相拟除虫菊酯产生抗性的一个重要机制,也是产生交互抗性的一个重要原因.     

家蝇对DDT和拟除虫菊酯的重要抗性机制——中枢神经系统的不敏感性

本文以电生理技术研究了四个品系的家蝇Musca domestica vicina Macq.中枢神经系统(CNS)对DDT、二氯苯醚菊酯和澳氰菊酯的敏感性,结果表明:三种抗性家蝇,DDT高抗品系(DDT-R)、二氯苯醚菊酯高抗品系(2C1-R)和溴氰菊酯高抗品系(Dec-R)的中枢神经系统(CNS)对三种杀虫剂的敏感性与敏感家蝇相比均明显降低,而且,GNS的不敏感性随杀虫剂LD₅₀的升高有逐渐上升的趋势.我们认为,CNS不敏感性是家蝇对DDT相拟除虫菊酯产生抗性的一个重要机制,也是产生交互抗性的一个重要原因.     

拟除虫菊酯的结构与害虫抗药性的关系

以家蝇Musca domestica vicina L.为试虫,用汰选方法研究了家蝇对六种不同拟除虫菊酯的抗性发展.结果表明,家蝇对不同化学结构和不同光学异构体组分的拟除虫菊酯抗性差别很大.对溴氧菊酯、顺式氯氰菊酯抗性发展很快,氯氰菊酯次之,氰戊菊酯、氰戍菊酯A和氰戊菊酯A_σ抗性发展较慢.用抗溴氰菊酯家蝇品系和点滴法测定了十种拟除虫菊酯和七种有机磷杀虫剂的毒力,讨论了它们之间的交互抗性和结构与抗性的关系.溴氰菊酯(抗性比值24.00)、氯氰嫡酯(抗性比值20.11)、顺式氯氰菊酯(抗性比值38.10)和二氯苯醚菊酯(抗性比值11.04),结构相近的交互抗性比较严重.氰戊菊酯(抗性比值4.64)、氰戊菊酯A(抗性比值5.97)、戊菊酯(抗性比值4.49)和氟氰菊酯(抗性比值4.12)化学结构中醇部分与溴氰菊酯相同、酸部分不同,它们与溴氰菊酯交互抗性水平较低.联苯菊酯(抗性比值1.98)化学结构中酯和醇部分都与溴氰菊酯不同,其交互抗性水平较低,杀螟松等七种有机磷杀虫剂,除敌敌畏与溴氰菊酯有轻微交互坑性外,其它均无交互抗性.     

拟除虫菊酯抗性家蝇的交互抗药性研究

拟除虫菊酯的广泛使用使家蝇普遍产生了抗药性,为有效的控制家蝇的危害,需要了解家蝇对轮换或新杀虫剂的交互抗性状况。作者用点滴法测定了两个实验室汰选的拟除虫菊酯抗性家蝇品系对几种杀虫剂的交互抗性,结果表明:二氯苯醚菊酯和溴氰菊酯之间存在较高程度的交互抗药性;拟除虫菊酯抗性较高的家蝇对作用机制不同的新农药(多杀菌素、氟虫腈)表现较低程度的交互抗性。     

棉铃虫对拟除虫菊酯杀虫剂敏感性的修复及其乙酰胆碱酯酶的变化

利用生物测定和生物化学方法研究了抗药性棉铃虫Helicoverpa armigera(Hubner)对拟除虫菊酯敏感性修复及其体内乙酰胆碱酯酶的变化,结果表明：当去除药剂选择压后,棉铃虫对拟除虫菊酯的抗性为不稳定。随着停止用药的时间加长,敏感性增加。从田间收集的棉铃虫在室内饲养后第1代对拟除虫菊酯的抗性下降速度较迅速。特异性酶抑制剂对敏感和抗性棉铃虫种群的乙酰胆碱酯酶亲和力试验结果证实,乙酰胆碱酯酶在抗性棉铃虫对杀虫剂反应发生变化的过程中发生改变,这种酶的改变可能对棉铃虫抗药性的不稳定性有重要影响。     

北京地区家蝇对拟除虫菊酯的抗药性与α-乙酸萘酯(α-NA)酯酶的关系

 通过1988年以来对北京地区家蝇(Musca domestica L.)抗药性的研究表明,北京朝阳、回龙观、宣武、景陵地区的家蝇种群与海口种群LD_(50)比较,对溴氰菊酯的抗性为5.4—17.2倍,对二氯苯醚菊酯的抗性为2460—3080倍。不同抗性水平的家蝇种群中,α-NA确酶活性大于0.5(A600值(0.01头·15分))的个体频率与其溴氰菊酯和二氯苯醚菊酯的抗性程度具有显著相关(相关系数分别为0.94和0.98)。抗性程度较高的宣武种群平均酯酶活性为280μmol/(mg蛋白质·分),是海口敏感种群的10.5倍。海口种群α-NA酯酶的米氏常数值(Km)为4.49mol/L,分别是朝阳、回龙观、宣武种群的4.7、4.2和2.3倍,说明抗性种群α-NA酯酶对底物的亲合力高于相对敏感的海口种群。     

增效醚（PBO）对棉铃虫细胞色素P450的抑制作用及对拟除虫菊酯的？…

在增效醚（ＰＢＯ）对棉铃虫Ｊｅｌｉｃｏｖｅｒｐａ ａｒｍｉｇｅｒａ３龄细虫处理后的不同时段,细胞色素Ｐ４５０的含量受到不同程度的抑制,在处理后１ｈ,细胞色素Ｐ４５０的含量仅为对照的４３．９％,至处理后１２ｈ,细胞色素Ｐ４５０的含量下降到最低点,仅为对照的２３．４％,而处理后１８～２４ｈ,细胞色素Ｐ４５０被抑制的程度有所减弱,其含量分别为对照的８５．８％和７０．０％。生物测定结果表明,ＰＢＯ对所测定     

棉铃虫对氰戊菊酯等杀虫剂抗性的选育及其生化机理

从用药水平低的棉田采集棉铃虫Helicover pa armigera(Hubner),在室内恒温条件下以人工饲料饲养,用氰戊菊酯等4种杀虫剂和1种混合剂经点滴法分别逐代处理棉铃虫幼虫,以选育其抗药性。用氰戊菊酯选择15代,抗性达311倍;而用灭多威、甲基对硫磷和辛硫磷分别选择13代、14代及13代,抗性仅分别达10.8倍、3.5倍及5.2倍,抗性发展较慢;甲基对硫磷与辛硫磷的混合剂选择12代,抗性也只有4.8倍。氰戊菊酯和溴氰菊酯、三氟氯氰菊酯间存在明显的交互抗性。用生测法测定酶抑制剂和生化法测定酶活性的结果表明,棉铃虫对氰戊菊酯的抗性主要与幼虫体内多功能氧化酶和羧酸酯酶的活性提高有关。     

SUBSTRATE SPECIFICITY AND DEVELOPMENTAL CHANGES OF ACETYLCHOLINESTERASE IN COTTON BOLLWORM*

Abstract The substrate specificity and developmental changes of acetylcholinesterase (AChE) of cotton bollworm, Helicoverpa armigera Hübner, were investigated during 1991 to 1994. The insects were collected from Handan suburbs of Hebei Province and Guan County of Shandong Province. The results show that the specific activity and Michaelis constants (k_m) of AChE toward acetylthiocholine (ATCH) and acetyl-β-methyl-thiocholine (MeTCh) regularly varied with the developmental stage of cotton bollworm. The two peaks of the specific activity were observed respectively in the third instar and sixth instar of larvae. The specific activity of AChE in pupae was the lowest and that in heads of four-days moth was the highest in various developmental stages of cotton bollworms. The tendency of K_m and maximum velocity (V_max) was identical with the change of specific activity in the AChEs of cotton bollworm. The activation energy (Ea) of AChE toward MeTCh in pupae and adults was 3. 9–4. 3 times as much as that of, larvae in cotton bollworms from Handan of Hebei Province. It suggests that the spending energies of AChE for hydrolysing substrate are different in larva, pupa and adult. The optimum conditions of AChE reaction with ATCh in larvae were 50–100 mg of tissue weights for the amount of enzyme, 10–20 minutes for the reaction time, 35°C for the reaction temperature and 8. 0 for the reaction pH value.     

棉铃虫乙酰胆碱酯酶的底物专一性和发育期变化(英)

通过对河北省邯郸地区和山东省冠县的棉铃虫(Helicoverpa armigera H(?)bner)乙酰胆碱酯酶(AChE)研究,结果表明,棉铃虫乙酰胆碱酯酶对乙酰硫代胆碱(ATCh)和乙酰-β-甲基硫代胆碱(MeTCh)的比活力以及米氏常数(K_(?))值随其发育阶段呈有规律的变化,AChE比活力在幼虫期呈现两个高峰,一个在三龄,另一个在化蛹前;在蛹期AChE比活力没有明显的变化,而且比活力值比较低;到成虫期第4天有一个明显的高峰,比活力值高于其它任何虫态。K_(?)和最大反应速度(V_(max))的变化趋势基本上与比活力一致。棉铃虫AChE的K_(?)和比活力随其生长发育阶段的周期性变化对于指导用有机磷和氨基甲酸酯类杀虫药剂的化学防治具有重要的意义。不同地点采集到的棉铃虫AChE对AICh和MeTCh水解的活化能有所不同,邯郸地区的棉铃虫AChE水解MeTCh的活化能,蛹和成虫是幼虫期的3.9-4.3倍,而冠县棉铃虫水解MeTCh的活化能则变化不大。AChE水解ATCh的活化能,邯郸地区棉铃虫的AChE不同虫态间变化不大,冠县棉铃虫AChE,幼虫和成虫期约是蛹期的4倍。这说明不同生长发育时期,棉铃虫AChE对底物的水解所消耗的能量是不同的。棉铃虫幼虫AChE的最适反应条件是酶量以重量计为50-100mg,反应时间为10-20min,反应温度为35℃,反应体系的pH值为8.0。     

BIOCHEMICAL ASPECTS OF INSECTICIDE RESISTANCE IN COTTON BOLLWORM FROM HANDAN OF HEBEI PROVINCE*

Abstract The cotton bollworms, Helicoverpa armigera Hübner, collected from Handan of Hebei Province, have evolved high resistance to pyrethroid, organophosphate and carbamate insecticides, The sensitivity of acetylcholinesterase (AChEs) to paraoxon and methomyl varied with the development stages of the cotton bollworm. After the treatments with LD₅ and LD₅₀ of parathion and methomyl to the cotton bollworms, the affinity of AChE to acetylthiocholine (ATCh) and acetyl-β-bmethyl-thio choline (MeTCh) increased significantly except the treatment of parathion using LD₅₀ dosage while the sensitivity of AChEs to paraoxon significantly decreased. The sensitivity of AChEs to methomyl strongly increased in the treatment of parathion using LD₅₀ dosages while strongly decreased in other treatments. The affinity of carboxylesterase to β-naphthyl acetate (β-NA) was higher in groups of treatment with insecticides than in group of control. The glutathione-s-transferase (GST) activity significantly decreased in the induced groups using LD₅ dosages, while increased in the selection groups using LD₅₀ dosages. The effects of parathion and methomyl on the phosphatases of cotton bollworm were related to the dosages of application and the time after treatment and the effect on the alkaline phosphatase was stronger than on acid phosphatase.     

RESISTANCE ALLEVIATION IN THE LARVAL COTTON BOLLWORM TO FENVALERATE AFTER PRE-TREATMENT WITH BACILLUS THURINGIENSIS

Abstract  Resistance alleviation and mechanism in the 2nd instar larvae of one susceptible and two resistant strains of the cotton bollworm, Helicoverpa armigera to fenvalerate were studied at 24 h after the larvae were treated with Bacillus thuringiensis Berliner ( B.t. ) preparation. The results showed that responses of larvae with B. t pretreatment to fenvalerate were much more sensitive than those without B. t pretreatment. Compared with the susceptible strain (YZ-S), net ratios between LD₅₀s with and without B. t pretreatment in the two resistant strains increased approximate 62. 6% and 80. 9%, respectively) inhibition of specific inhibitors to esterases displayed that efficacy of malaoxon and paraoxon methyl to acetyl-cholinesterase increased from 66.1% to 99. 8% in vitro and in vivo ; dynamic factors of acetylcholinesterase were significantly changed, in which K _m and V _max values decreased from 45. 58% to 68. 62% and K _i values of malaoxon and paraoxon methyl to acethylcholinesterase increased approximate 60%. It suggested that the sensitivity of the 2nd instar larvae of resistant H. armigera to fenvalerate might increase after B. t pretreatment for 24 h, and change of acetylcholinesterase was an important factor during resistance alleviation by B. t pretreatment. The research showed that it is practicable to bring the coordinated use of B. t and chemical insecticides in IPM system.     

棉铃虫对氰戊菊酯抗性遗传分析

本文采用剂量对数-死亡机率值回归线(LD-P线)分析法, 利用室内选育的棉铃虫 Heliccverpa armitera(Hubner)对氰戊菊酯抗性晶系和敏感品系,研究了棉铃虫对氰戊菊酯的抗性遗传规律。结果表明,棉铃虫对氰戊菊酯的抗性为多基因遗传,其主要基因为不完全显性,抗性不属性连锁遗传。利用增效剂对抗性机理进行的研究表明,多功能氧化酶(MFO)是棉铃虫对氰戊菊酯产生抗药性的主要因子,因此,可以推断多功能氧化酶基因为不完全显性。     

棉铃虫外生殖嚣的超微结构及其变异

本文对棉铃虫片Helicoverpa armigera(Hubner)雌雄外生殖器的一般构造和超微结构进行了较细致的研究。并与其近缘种作了比较研究。结果表明：在一般形态方面,棉铃虫种群内个体间变异较大,种群间分化较小：在雄性阳茎端囊的弯折数、大刺数及抱器瓣的长宽比等特征上与近缘种间有一定的重叠。在超微结构方面,种群内个体间、种群间均变异不大,但与近缘种间在雄性阳茎端囊刺构造上却有明显的、间断的差异,这一差异为近缘种的鉴别 提供了新的、可靠的特征。     

棉铃虫种群适合度研究

本试验比较了我国各棉区棉铃虫Helicoverpa armzgcra(Hubner)种群幼虫期和蛹期发育速度与温度的关系,并模拟了长江流域种群和华北种群在北京地区的发育动态。研究结果表明在20℃～30℃温区内不同地理种群之间的发育速度无明显的感温分化现象,但在自然条件下长江流域种群和华北地区种群的蛹滞育动态则有显著的区别,如湖南衡阳种群和四川简阳种群50%蛹滞育的时间较北京种群晚30d和22d。对各地理种群发育动态、北京地区气候特点和滞育蛹越冬试验结果的综合分析表明,北京地区应为棉铃虫温带生态型生态区北界,棉铃虫亚热带生态型在华北气候环境下不能完成年生活史。     

棉铃虫蛹和成虫形态特征的数值分析

通过对棉铃虫Helicoverpa armigera(Hubner)及其近缘种的蛹和成虫进行了形态特征变异的数值分析,结果表明：棉铃虫种群内个体变异较大,但种群间相对分化较小,无明显的地理分化,也没有发现棉铃虫种群有稳定变异的地理特征;但发现雄性抱器冠的长、宽、抱器瓣长宽比及抱器瓣长与冠宽比4个特征与纬度有一定的相关性,其相关系数分别为：-0.612,-0.699,0.693和0.691。尽管如此,棉铃虫还是相对比较单一的一个种,而近缘种在阳茎刺和抱器瓣的形态及阳茎端囊上的大刺数等方面有明显而稳定的差异和间断。