氰戊菊酯、胺菊酯对海洋藻类、贝类的毒性研究

本文研究了新型杀虫剂氰戊菊酯、胺菊酯对海洋藻类（金藻、小球藻）和贝类（紫贻贝、扇贝）的毒性。经实验分别得出了两种农药对金藻、小球藻生长的半数抑制浓度（ＥＣ５０）和对贻贝、扇贝的急性半致死浓度（９６ｈＬＣ５０）值。实验结果表明，贻贝对两种农药的敏感性最低，其它三种生物对两种农药的反应各不相同．     

家蚕品种野三元耐微量拟除虫菊酯类农药污染新品系的筛选

基于为培育耐农药污染家蚕品种和研究家蚕对农药的耐受性机制提供基础材料的目的,对包括家蚕四元杂交品种野三元中2个含野桑蚕血统的中系亲本野A、野B和2个日系亲本84Y2、784等在内的160份家蚕品种资源,以0.01 mg/L杀灭菊酯添食后进行耐药性筛选,供试家蚕品种中的野B、辐射诱变品种辐7对微量杀灭菊酯具有较强的耐受能力。进一步以0.1～0.3 mg/L杀灭菊酯添食诱导后,自野A、野B中筛选建立了新的耐受性品系野AJ、野BJ,另以辐7为母本,分别以84Y2、784为父本杂交后培育获得新的耐受性品系辐84Y2、辐784。从以上4个新品系中均获得了添食微量杀灭菊酯后幼虫存活率100%的蛾区。4个对微量杀灭菊酯具有较强耐受性的新品系,进一步通过农药诱导选择及系统选择提高和固定其耐受性水平后,可作为耐农药污染新品种的育种材料。     

杀铃脲及其混剂对麦田天敌影响的评价

杀铃脲属昆虫几丁质合成抑制剂．它不仅对害虫具有较强的毒杀作用，而且对环境和天敌安全。在用该药进行小麦粘虫防治试验的同时，还做了该药对天敌作用的室内测定和田间调查．明确了杀铃脲单剂不同浓度、不同剂型对麦田瓢虫、蜘蛛等主要天敌无杀伤作用，室内处理后的试虫仍能正常化蛹和羽化。杀蛉脲混剂低剂量对天敌无影响，中剂量有一定影响，高剂量影响严重。     

溴氰菊酯等杀虫剂防蚜保瓢的初步研究

1984年研究了溴氰菊酯、氰戊菊酯和氯氰菊酯对棉蚜及其天敌异色瓢虫的影响,结果表明,氰戊菊酯对异色瓢虫的毒力较溴氰菊酯、氯氰菊酯及乐果为低。在瓢虫发生盛期,防治棉蚜宜使用氰戊菊酯。     

Cloning of Partial Sodium Channel Gene From Strains of Fenvalerate-Resistant and Susceptible Cotton Aphid(Aphis gossypii Glover)

The strain of fenvalerate-resistant cotton aphids was selected using fenvalerate insecticide in the laboratory, the resistance factor of the strain was 199.54. Three degenerate primers were designed and used to perform PCR amplification. A cDNA encoding partial sodium channel gene was cloned from the fenvalerate-resistant and -susceptible strains. There were two nucleotide acid differences between fenvalerate-resistant strain and -susceptible strain, resulting in an amino acid mutation, Met→Leu. It is predicted that the mutation is related to the cotton aphid resistance to fenvalerate.     

Mechanism of fenvalerate-withdrawal-dependent recovery in metabolism of a catfish, Clarias batrachus

The effects of protein synthesis inhibitors on fenvalerate-withdrawal-dependent recovery in citrate synthase (CS), glucose 6-phosphate dehydrogenase (G6-PDH), lactate dehydrogenase (LDH), RNA, and protein of brain, liver, and skeletal muscle of Clarias batrachus were studied to explore possible mode of action of a pyrethroid insecticide at metabolic level. The administration of actinomycin D or cycloheximide inhibited partially or completely the withdrawal-dependent increase in enzyme activities, RNA, and protein contents, substantiating de novo synthesis of these macromolecules during recovery. The inhibition was more pronounced in response to cycloheximide reflecting recovery in translation process. This also suggests the possibility of fenvalerate-induced impairment of metabolism through inhibition of enzyme synthesis.     

氰戊菊酯抗性小菜蛾雌成虫对15种植物挥发物的行为反应

为了研究小菜蛾对植物挥发物的行为反应与抗性水平之间的关系,采用昆虫Y形嗅觉仪,测定氰戊菊酯抗性和敏感品系小菜蛾雌成虫对15种植物挥发性物质的行为反应。结果表明:抗性品系小菜蛾和敏感品系小菜蛾均对5种绿叶气味(反-2-己烯醛、顺-3-己烯醇、顺-3-己烯乙酸酯、正己醇和正己醛)以及苯甲醛、桉树脑的趋向反应率显著高于石蜡油(P0.05,χ2检验),表明这7种物质对小菜蛾雌蛾均有一定的诱集作用。在8种萜烯类物质中,敏感小菜蛾雌蛾分别对2种物质(牻牛儿醇、D-柠檬烯)的趋向反应率与石蜡油间无显著差异(P0.05,χ2检验);而抗性小菜蛾雌蛾分别对4种物质(牻牛儿醇、(R)-(-)-香芹酮、里那醇、(1R)-(+)-α-蒎烯)的趋向反应率与石蜡油均无显著差异。抗性品系小菜蛾停留在Y形管主臂上的比例均少于敏感品系,与敏感品系相比,在较低的氰戊菊酯抗性种群水平下(6.52倍),并没有显著改变小菜蛾雌蛾对寄主植物挥发物的行为反应趋势,但是抗性水平下却加剧小菜蛾趋向反应的比率。     

混合微生物对氰戊菊酯的降解作用

[目的]研究混合微生物对氰戊菊酯的降解作用。[方法]以氰戊菊酯为目标污染物,通过富集驯化培养获得对该污染物降解效果较好的混合培养微生物,用该微生物作为降解菌源,研究其对氰戊菊酯的生物降解特性。[结果]该混合培养微生物中氰戊菊酯降解菌在初始pH值为5.5~7.5条件下生长均较好,具有一定的耐酸性和耐碱性;在25~45℃条件下生长较好,最适生长温度为33℃;该混合微生物生长适应时间为84 h,此时氰戊菊酯去除率可以达到55%。[结论]混合培养物能利用氰戊菊酯作为生长的唯一碳源、氮源和能源且对氰戊菊酯具有一定的降解作用。     

Effect of fenvalerate on the reproduction and fitness costs of the brown planthopper, Nilaparvata lugens and its resistance mechanism

The brown planthopper (BPH), Nilaparvata lugens Stål, is a primary insect pest of cultivated rice, and its effective control is essential for crop production. However, in recent years, outbreaks of the brown planthopper have occurred more frequently in China. In order to determine the causes and mechanisms of insecticide-induced BPH resurgence and perform population management, we conducted the following studies. By the topical application method, our results showed that, fenvalerate acted as stimulus of fecundity from 3.50 × 10⁻³ to 2.02 × 10⁻² μg/female in the BPH. Apart from 7.00 × 10⁻³ μg/female, the number of hatched nymphs was increased gradually with an increase in application dose from 3.50 × 10⁻³ to 1.74 × 10⁻² μg/female. After continuous selection with fenvalerate for 11 generations by the rice-stem dipping method, a resistant strain was achieved with medium resistance to fenvalerate (RR 39.22). Life table study indicated that the resistant strain (G4 and G8) showed reproductive advantages, including increased female ratio, copulation rate and fecundity. But the hatchability of resistant strain was lower. The survival rate and emergence rate were significantly lower in G4 and G8 resistant strain. Resistant strains in G4 and G8 showed a fitness advantage (1.04 and 1.11), and the number of offspring in G8 generation was higher than that in G4 generation. The significant difference detected between resistant insects (G4, G5, G8 and G9) and S-strain contains not only the effect of resistant selection but also the effect of continuous rearing itself. Hence it was concluded that the BPH had the potential to develop high resistance against fenvalerate and the induction of the nymphs by sublethal doses of fenvalerate was of importance in the BPH population management, particularly in the predicting. Further studies demonstrated that triphenyl phosphate (TPP) and diethyl maleate (DEM) had no synergism on fenvalerate. However, piperonyl butoxide (PBO) displayed significant synergism in susceptible strain (1.97) and resistant strain (2.73). We concluded that esterase and glutathione S-transferase play little role in fenvalerate detoxification. The increase of the P450-monooxygenases detoxification is an important mechanism for fenvalerate resistance. Because their resistant populations had a fitness advantage, we should pay close attention to the occurrence of BPH and use other functionally different insecticides to control the BPH.