灭多威与杀螟硫磷混剂的筛选及药效评价

在室内条件下采用浸渍法和喷雾法分别测定了灭多威、杀螟硫磷及其以不同比例混用对豆蚜和粘虫的增效作用。结果表明，灭多威与杀螟硫磷以１：１、１：３、１：５、１：７和１：９比例混用对蚜虫、粘虫表现出不同程度的增效作用，其中以１：７混用增效最明显，共毒系数分别为２４９．０３和１８０．３０，其毒效分别是灭多威的１．６１和０．９３倍，杀螟硫磷的２．７０和２．０８倍。田间小区试验表明，灭多威与杀螟硫磷混剂（１：７）对棉蚜和棉铃虫的防治效果明显优于杀螟硫磷，而稍优于或接近于灭多威     

丙溴磷、辛硫磷及其混剂对二化螟的毒力测定和田间药效试验

采有点滴法测定丙溴磷、辛硫磷及其混剂对二化螟的毒力,结果表明,丙溴磷与辛硫磷混配,各个配比均有增效作用,其中以6:19(有效成分)的配比增效作用最大,毒性比率和共毒系数分别为1.71和177.16。田间试验表明,丙溴磷与辛硫磷以6:19的混剂对二化螟有较好的防治效果,室内结果在田间试验中得到验证。     

灭多威与杀虫剂的联合毒力研究

室内采用浸渍法、喷雾法和点滴法分别进行了灭多威与杀螟硫磷、灭多威与异丙威对蚜虫和粘虫的联合毒力测定。结果表明灭多威与杀螟硫磷以１：７比例混配对蚜虫和粘虫均表现为增效作用,共毒系数（ＣＴＣ）分别为２４９．０３和１８０．３０;灭多威与异丙威以１：２比例混配对蚜虫和粘虫表现为显著增效,共毒系数分别为２３５．４５和２７４．３０。比较了３种生测方法对灭多威的杀虫活性影响     

苏云金芽孢杆菌液剂与杀虫双混用对稻纵卷叶螟的增效作用

室内生物测定表明，Ｂｔ液剂和不同比例的２５％杀虫双混用对稻纵卷叶螟都有不同程度的增效作用，其中３：１和１：１（Ｂｔ：杀虫双）混用增效作用最为明显，共毒系数分别为２６５和２９８。１：１混用的毒效为杀虫双单用的１．７１倍。田间小区试验表明，１：１混用的防治效果接近于同剂量的杀虫双。     

杀虫单与有机磷杀虫剂混配对粘虫的增效作用研究

采用浸叶法测定了杀虫单分别与几种有机磷杀虫剂混配对粘虫3龄幼虫的联合毒力。结果表明杀虫单与敌百虫以1：3比例混配对粘虫表现为显著增效，共毒系数（CTC）为268．11；杀虫单与三唑磷以1：1、4：3和1：2的比例混配对粘虫表现为增效作用。共毒系数（CTC）分别为132．98、140．21和132．74：杀虫单与毒死蜱以4：1的比例混配表现为增效作用，共毒系数（CTC）为192.91。     

几种杀虫剂对桔小实蝇老熟幼虫的毒力测定

在室内条件下采用浸渍法,分别测定了10种杀虫剂对桔小实蝇老熟幼虫的毒力,二元混剂的共毒系数。供试杀虫剂对桔小实蝇老熟幼虫的毒性大小依次为:乐斯本>害极灭>辛硫磷>米乐尔>功夫>敌敌畏>阿克泰>好年冬>歼灭乳油>敌百虫;敌百虫和辛硫磷（1:9）的共毒系数为266.74,辛硫磷和乐斯本（1:1）的共毒系数为330.48。     

丙溴磷与哒螨灵对黄曲条跳甲毒力最佳配比的筛选

采用Potter喷雾法测定了丙溴磷与哒螨灵混配后对黄曲条跳甲成虫的联合毒力及混剂的最佳配比。结果表明,丙溴磷与哒螨灵按90∶10、84∶16、80∶20混配时,3种配伍的药液对黄曲条跳甲成虫的毒力相差不大,其共毒系数分别为141.00、154.62和149.51;当丙溴磷与哒螨灵的比例为30∶70时联合毒力最强,共毒系数为180.76。     

农药复配最佳增效配方筛选方法的探讨

复配农药增效作用的定量测定是配方筛选的重要依据。以斜纹夜蛾（Ｓｐｏｄｏｐｔｅｒａ ｌｉｔｕｒａ）为试虫,采用Ｐｏｔｔｅｒ喷雾法测定了氯氰菊酯、喹硫磷、毒死蜱、丙硫磷、丙溴磷、灭多威、敌敌畏对斜纹夜蛾２龄幼虫的毒力。根据共毒因子法确定氯氰菊酯与喹硫磷混配为最佳配伍。根据等效线法中相加作用线的十等分点氯氰菊酯与硫磷的配比分别为１：１８、１：８、３：１４、１：３、１：２、３：４、７：６、２：１、９：２,     

棉铃虫抗辛硫磷品系的代谢抗性机理

通过重复回交和药剂选择,将棉铃虫Phoxim-R抗性品系对辛硫磷的抗性导入到BK77敏感品系中,得到棉铃虫BK77-R抗性品系,BK77-R和BK77为一对近等基因系。BK77-R抗性品系对辛硫磷的抗性达155倍,对溴氰菊酯有高水平交互抗性(抗性倍数248倍),对灭多威和硫丹有中等水平交互抗性, 分别为31倍和11倍,对丙溴磷有低水平交互抗性(4倍)。在BK77-R抗性品系中,脱叶磷(DEF,酯酶抑制剂)对辛硫磷、灭多威和硫丹具有增效作用,增效倍数分别为7倍、2倍 和1.9倍;增效醚(PBO,氧化酶抑制剂)对溴氰菊酯、灭多威和辛硫磷的增效倍数分别为21倍、2.2倍和1.7倍。与BK77敏感品系相比,BK77-R抗性品系的酯酶和多功能氧化酶活性均显著提高,而谷胱甘肽S-转移酶活性没有明显变化。上述结果表明,酯酶解毒代谢在棉铃虫BK77-R品系对辛硫磷的抗性中起重要作用,酯酶和多功能氧化酶解毒作用增强是该抗性品系对不同类型药剂产生交互抗性的重要原因。     

辛硫磷对氰戊菊酯在抗性家蝇体内的增效机制

作者就辛硫磷对氰戊菊酯在抗拟除虫菊酯类杀虫剂的家蝇体内的增效作用进行了初步的研究。结果表明：在辛硫磷与氰戊菊酯同时存在时（质量比为２：１），家蝇体内未被降解的氰戊菊酯原化合物含量显著高于只使用等剂量氰戊菊酯时的对照处理（２．６－４．６倍）。同时，家蝇对氰戊菊酯的氧化代射速率降低（１７－４８％）。这些结果可能是辛硫磷对氰戊菊酯增效的主要作用机制，并对延缓害虫抗药性发展有积极的作用。     

Efficacy of insecticide mixtures against pyrethroid‐ and organophosphate‐resistant populations of Spodoptera litura (Lepidoptera: Noctuidae)

BACKGROUND: Spodoptera litura (F.) is an important pest worldwide, with over 112 host plants, and is exposed to insecticides throughout the year, resulting in the rapid development of resistance. Insecticide mixtures can delay the development of resistance more effectively than sequences or rotations. Cypermethrin, deltamethrin, profenofos, chlorpyrifos and fipronil were assessed separately and in mixtures against laboratory susceptible S. litura and two field‐collected populations. RESULTS: The field‐collected population from Khanewal (KWL) was significantly more resistant to cypermethrin, deltamethrin, chlorpyrifos and profenofos than one collected from Muzaffar Garh (MGH). Mixtures of cypermethrin + chlorpyrifos or profenofos and of deltamethrin + chlorpyrifos or profenofos at 1:1, 1:10 and 1:20 ratios significantly increased (P < 0.01) toxicity to cypermethrin and deltamethrin in field populations. The combination indices of cypermethrin + chlorpyrifos at 1:1 and 1:10 ratios and cypermethrin + fipronil at 1:1, 1:10 and 1:20 ratios for the KWL strain and of cypermethrin + profenofos or fipronil at 1:1, 1:10 and 1:20 ratios for MGH were significantly below 1, suggesting synergistic interactions. The inhibitors DEF and PBO largely overcame resistance to deltamethrin, cypermethrin and profenofos, suggesting that resistance to the insecticides was associated with esterase and monooxygenase detoxification respectively. CONCLUSION: Chlorpyrifos, profenofos and fipronil could be used in mixtures to restore cypermethrin and deltamethrin susceptibility. These findings may have considerable practical implications for S. litura resistance management. Copyright © 2008 Society of Chemical Industry     

苏云金芽孢杆菌液剂与杀虫双混用对稻纵卷叶螟的增效作用

室内生物测定表明,Bt液剂和不同比例的25％杀虫双混用对稻纵卷叶螟都有不同程度的增效作用,其中3:1和1:1(Bt:杀虫双)混用增效作用最为明显,共毒系数分别为265和298。1:1混用的毒效为杀虫双单用的1.71倍。田间小区试验表明,1:1混用的防治效果接近于同剂量的杀虫双。     

辛氰和乐氰混剂对甘蓝桃蚜抗性演化的影响

用辛硫磷与氰戊菊酯,乐果与氰戊菊酯的最佳配比及其相应单剂对甘蓝桃蚜进行抗性选育,汰洗２０代时桃蚜对两种混剂的抗性,分别为４．２０和２．６８倍,比相应单剂的抗性发展速度慢,尤其比氰戊菊酯单剂（２８９倍）更慢,表明上述两种混剂都可延缓桃蚜的抗性发展。用酶抑制剂进行增效应用测定结果表明：Ｋ１和ＴＰＰ对辛硫磷和乐果都有增效作用,尤以Ｋ１的增效作用更显著,其增效比分中辊为１０５３和３８,说明桃蚜对辛硫磷和乐     

辛硫磷、氰戊菊酯及其混剂对棉铃虫生长发育及雌性生殖的影响

用组织化学和生化分析法探讨了辛硫磷，氰戊菊酯和辛氰混剂对棉铃虫生长发育及雄性生殖功能的影响。结果表明：（1）2种单剂与混剂处理后雄蛹重量降低，化蛹率下降，对蛹历期无影响；（2）3种药剂对真核精子发生有抑制作用，而对无核精子的发生无影响；（3）辛硫磷处理后附腺和精包腺的蛋白质含量下降，氰戊菊酯和混剂对附腺和精包腺无显著影响。（4）辛硫磷处理后的雄蛾与正常的雄蛾配对，其交配力显著下降，雌蛾产有效卵显著减少；（5）辛氰混剂在影响棉铃虫生长发育和真核精子发生方面具有明显的增效作用。     

辛硫磷、氰戊菊酯及其混剂对棉铃虫生长发育及雄性生殖的影响

用组织化学和生化分析法探讨了辛硫磷、氰戊菊酯和辛氰混剂对棉铃虫生长发育及雄性生殖功能的影响。结果表明:(1)2种单剂与混剂处理后雄蛹重量降低,化蛹率下降,对蛹历期无影响;(2)3种药剂对真核精子发生有抑制作用,而对无核精子的发生无影响;(3)辛硫磷处理后附腺和精包腺的蛋白质含量下降,氰戊菊酯和混剂对附腺和精包腺无显著影响;(4)辛硫磷处理后的雄蛾与正常的雌蛾配对,其交配力显著下降,雌蛾产有效卵显著减少;(5)辛氰混剂在影响棉铃虫生长发育和真核精子发生方面具有明显的增效作用。     

棉铃虫抗药性监测及其化学防治

1997～1998年,用浸叶接虫法测定了山西省南部棉区永济县棉铃虫对常用5种农药的抗药性,同时进行了多种农药防治棉铃虫田间药效试验研究。结果表明,永济县棉铃虫对氯氰菊酯已产生了高等水平的抗药性,对久效磷产生了中等水平的抗药性,但对灭多威仍未产生明显的抗药性。水胺硫磷、甲基对硫磷、氯氟氰菊酯、氯氰菊酯、丙·辛乳油和甲对·氯乳油等农药防治永济县二代棉铃虫效果较好     

Synergism between fungicides with different mechanisms of action against acylalanine-resistant strains of Phytophthora spp.1

The authors have studied the efficacy of two systemic compounds, cymoxanil and propamocarb, used as partners of acylalanines, in limiting mycelial growth of acylalanine-sensitive and resistant strains of Phytophthora capsici and P. nicotianae var. parasitica. The fungicidal activity of the single components was compared to that of the different mixtures, at various ratios. The degree of synergy was calculated using the method of Wadley. The results obtained indicate synergistic interactions of various intensities: synergistic factors (SF) up to seven were found. The highest synergistic effects were observed in the case of resistant Phytophthora strains.     

中生菌素和纳他霉素复配制剂防治番茄灰霉病的协同增效作用

为提高现有生物农药对番茄灰霉病的防治效果,本文研究了中生菌素和纳他霉素的复配制剂对番茄灰霉病菌菌丝生长和孢子萌发的抑制作用以及田间防病效果,确定了二者复配的增效作用及适宜配比。结果表明,中生菌素和纳他霉素质量比为9:1和1:1时,复配制剂对菌丝生长的抑制作用明显,具增效作用,增效系数分别为3.6348和1.7145;二者质量比为9:1、7:3和1:1时,对孢子萌发的抑制具有增效作用,增效系数分别为1.7268、1.6335和1.5336。田间试验表明,3%中生菌素·纳他霉素可湿性粉剂(9:1)500倍稀释液防病效果最好,施药7 d后对叶片和果实上的灰霉病防效分别达到81.04%和78.48%,显著高于单一制剂的防病效果。上述结果表明,适当配比的中生菌素与纳他霉素复配制剂对番茄灰霉病的防治效果显著增强,对生物农药的田间应用具有实际指导意义。     

Note: Insecticide resistance in<Emphasis Type="Italic">Helicoverpa armigera</Emphasis> from cotton-growing areas in Turkey

Insecticide resistance inHelicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) is one of the most important constraints on cotton production in Turkey. We investigated the susceptibility ofH. armigera strains collected from cotton fields in the Adana, Hatay and Antalya provinces to insecticides which are in wide use. LD₅₀ values for tralomethrin, lambda-cyhalothrin, endosulfan, profenofos and methomyl were determined by topical bioassay. At the LD₅₀ levels, resistance ratios for tralomethrin were 24.7-, 19.7- and 15.7-fold in the Adana, Hatay, and Antalya strains, respectively; and for lambda-cyhalothrin were 41-, 20-and 40-fold, respectively. Resistance ratios ranged from 1.2- to 2.1-fold in all field strains for endosulfan, profenofos and methomyl, with no significant resistance. These results suggest the presence of resistance to tralomethrin and lambda-cyhalothrin inH. armigera strains collected from cotton fields, but no resistance to endosulfan, profenofos or methomyl could be observed.     

Genetics and mechanism of resistance to deltamethrin in a field population of Spodoptera litura (Lepidoptera: Noctuidae)

BACKGROUND: Spodoptera litura (F.) causes enormous losses in many economically important crops. The genetics of insecticide resistance has been extensively studied in several insect pests, but there is a lack of information on S. litura. Therefore, the genetics and mechanisms of the resistance of S. litura to deltamethrin were investigated. RESULTS: Bioassays at generation G1 gave resistance ratios of 9, 5, 41, 52 and 49 for deltamethrin, cypermethrin, profenofos, chlorpyrifos and triazofos respectively, when compared with the susceptible Lab-PK strain. Bioassays at G4 with a deltamethrin-selected population (Delta-SEL) showed that selection gave resistance ratios of 63 and 7 for deltamethrin when compared with the Lab-PK and UNSEL strains respectively. Cross-resistance to other insecticides tested was observed in the selected population. A notable feature of the Delta-SEL strain was that resistance to deltamethrin, cypermethrin, profenofos and chlorpyrifos did not decline over the course of five generations. Synergism tests with microsomal oxidase (MO) and esterase-specific inhibitors indicated that the deltamethrin resistance was associated with MO and, possibly, esterase activity. Reciprocal crosses between the Delta-SEL and Lab-PK strains indicated that resistance was autosomal and incompletely dominant. A direct test of monogenic inheritance suggested that resistance to deltamethrin was controlled by more than one locus. CONCLUSION: Stability and dominance of resistance and cross-resistance suggest that insecticides with different modes of action should be recommended to reduce pyrethroid selection pressure.