Comparative Efficacies of Next-Generation Insecticides Against Yellow Stem Borer and Their Effects on Natural Enemies in Rice Ecosystem

The efficacies of some next-generation insecticides against the rice yellow stem borer(YSB),Scirpophaga incertulas(Walk.), and their compatibilities with natural enemies were investigated during 2014 and 2015. Three newer insecticides, chlorantraniliprole 0.4% G, dinotefuran 20% SG, and methoxyfenozide 24% SC, and two commonly used insecticides, carbufuran 5 G and quinalphos 25 EC,were evaluated in the field for their efficacies against YSB and their non-target effects on natural enemies.Application of chlorantraniliprole 0.4% G at 10.96 kg/hm^2 resulted in the greatest reduction in YSB infestation(deadhearts and whiteheads) and greatest increase of yield compared to the untreated control plots, followed by methoxyfenozide 24% SC at 0.41 L/hm^2, dinotefuran 20% SG at 0.15 kg/hm^2,carbufuran 5 G at 10.96 kg/hm^2, and quinalphos 25 EC at 1.50 L/hm^2. All the insecticides reduced the numbers of predators viz., lady bird beetles, wolf spiders, carabid beetles, earwigs, green mirid bugs, and damselflies. Numbers of adults of the egg parasitoids Trichogramma sp., Telenomus sp. and Tetrastichus sp. were significantly reduced in insecticide-treated plots compared to untreated control plots. In all field trials, the harmful effects of the five insecticides were in the following rank order(least harmful to most harmful): chlorantraniliprole 0.4% G, carbufuran 5 G, dinotefuran 20% SG, methoxyfenozide 24% SC,and quinalphos 25 EC. On the basis of reduction in YSB infestation, increase in grain yield, and compatibility with natural enemies, chlorantraniliprole 0.4% G was proved to be the best of all the insecticides for YSB management system, although the study suggested minimizing its retail price for enhancement of cost effectiveness in farmers' fields.     

MBF2转录调控小菜蛾谷胱甘肽S-转移酶代谢氯虫苯甲酰胺的功能

【目的】探究转录调控因子MBF2 (multiprotein bridging factor 2)调控小菜蛾（Plutella xylostella）体内谷胱甘肽S-转移酶（glutathione S-transferase,GST）的功能,及其在小菜蛾抗氯虫苯甲酰胺中的作用,为阐明小菜蛾对氯虫苯甲酰胺的解毒代谢机制提供理论依据。【方法】采用浸叶法测定敏感（SS）、广东连州（LZ）、云南通海（TH）3个小菜蛾种群对氯虫苯甲酰胺的抗性水平,酶动力学法测定3个种群的GST活性;使用实时荧光定量PCR(RT-qPCR)分析MBF2在不同抗性种群小菜蛾中的表达差异;采用氯虫苯甲酰胺LC50诱导12 h,分析其对小菜蛾MBF2的诱导表达作用;应用RNA干扰（RNA interference,RNAi）技术研究MBF2对GST基因的调控作用,并测定沉默MBF2后小菜蛾的GST活性;结合沉默后小菜蛾对药剂的敏感性变化,验证MBF2在小菜蛾抗氯虫苯甲酰胺中的作用。【结果】两个抗性种群（TH和LZ）相较SS种群分别达到了中抗及高抗的水平,TH和LZ抗性倍数分别为54.27和289.58;TH和LZ小菜蛾...     

有机硅助剂对氯虫苯甲酰胺防治稻纵卷叶螟的增效作用研究

为探索有机硅助剂Silwet408对杀虫剂药液理化性能的影响及药液雾滴在稻叶上的行为与对稻纵卷叶螟Cnaphalocrocis medinalis Guenée防效的内在关系,在室内条件下研究了在200 g/L氯虫苯甲酰胺悬浮剂稀释液中添加助剂Silwet408后表面张力、黏度、pH值以及在稻叶上最大持留量的变化,借助OCG法对叶片的表面特性进行表征,围绕叶片倾角分析了单个雾滴在稻叶上的黏附行为,并进行了田间药效试验。结果表明:水稻叶片正、反面表观表面自由能分别为31.48 mJ/m^2和34.19 mJ/m^2;倒二叶和倒三叶的叶角较小,分别为(11.09±2.74)°和(19.98±5.67)°,表明水稻为高倾角叶片形态,不利于雾滴在稻叶上的黏附。200 g/L氯虫苯甲酰胺悬浮剂4000倍和5000倍稀释液的表面张力分别为(44.64±1.04)mN/m和(46.14±0.62)mN/m,均大于稻叶的表观表面自由能,其药液的单个雾滴在79°和70°的倾角稻叶上均呈滚落状态;添加125 mg/L的Silwet408后,药液的表面张力小于稻叶的表观表面自由能,单个雾滴能够黏附在倾角稻叶上并润湿,同时药液在稻叶上的最大持留量也呈极显著增加;200 g/L氯虫苯甲酰胺悬浮剂5000倍稀释液的pH值和黏度在添加Silwet408前后变化不大。田间试验结果表明,添加125 mg/L的Silwet408后,200 g/L氯虫苯甲酰胺悬浮剂5000倍稀释液对稻纵卷叶螟药后14 d的保叶效果和杀虫效果均显著提高。综合研究结果表明,在200 g/L氯虫苯甲酰胺悬浮剂5000倍稀释液中添加125 mg/L的Silwet408可使喷雾药液与水稻植株特性相匹配,进而提高氯虫苯甲酰胺对稻纵卷叶螟的防治效果。     

Comparative impact of an anthranilic diamide and other insecticidal chemistries on beneficial invertebrates and ecosystem services in turfgrass

BACKGROUND: Chlorantraniliprole, the first anthranilic diamide insecticide labeled for turf, combines strong selective activity against key pests with low vertebrate toxicity. The hypothesis that it is less disruptive to beneficial invertebrates and their ecosystem services than are other prevailing insecticide classes was tested. Plots in golf course settings were treated with chlorantraniliprole, or with a representative nicotinoid (clothianidin), pyethroid (bifenthrin) or a combination (clothianidin–bifenthrin) formulation. Non‐target effects were assessed via pitfall traps (epigeal predators), Tullgren funnel extraction (soil microarthropods), hand sorting (earthworms), counting ant mounds and earthworm casts on tees and putting greens, assessing predation on sentinel pest eggs and comparing grass clipping decomposition in treated versus untreated turf. RESULTS: Chlorantraniliprole had little or, in most cases, no impact on predatory or soil invertebrates, predation or decomposition. Each of the other insecticides temporarily reduced abundance and activity of one or more predator groups. Clothianidin and the clothianidin–bifenthrin combination retarded grass clipping decomposition, and the combination suppressed earthworms and casts more than did carbaryl, a toxic standard. CONCLUSION: Chlorantraniliprole is compatible with conservation biocontrol and a good fit for industry initiatives to use relatively less toxic pesticides. One caveat is that its use on golf courses may require targeted management of ant mounds and earthworm casts that are suppressed as a side effect by some less selective insecticides. Copyright © 2011 Society of Chemical Industry     

Effects of Pesticide Applications on the Biochemical Properties of Transgenic cry 2A Rice and the Life History Parameters of Nilaparvata lugens Stål (Homptera: Delphacidae)

Effects of transgenic Bt rice on non-target pests following pesticide applications plays an important role in evaluating the ecological safety of transgenic rice. Changes of the life history parameters of laboratory population of Nilaparvata lugens feeding on transgenic Bt rice T2A-1 and its parental line cv. MH63 as the control, and the contents of oxalic acid and soluble sugar following three pesticides (triazophos, jinggangmycin and chlorantraniliprole) treatments were investigated in this paper. Results showed that the population parameters of N. lugens and the physiological and biochemical parameters of rice did not differ significantly between T2A-1 and MH63 without pesticide application. But, the emergence rate (ER), the nymphal number of next generation (NN), and the index of population trend (IP) on T2A-1 treated with 10 mg L^?1 of triazophos were significantly higher than those on MH63, respectively, while the hatchability (HB) on T2A-1 treated with the three pesticides were obviously lower than those on MH 63. Furthermore, the content of oxalic acid in MH63 treated with 20 mg L^?1 triazophos and, 40 and 80 mg L^?1 chlorantraniliprole was significantly higher than that in T2A-1, while the content of soluble sugar in T2A-1 treated with 400 mg L^?1 jinggangmycin was significantly higher than that in MH63. The results above indicated that triazophos in a low dose could cause a more favor of T2A-1 to population growth of N. lugens compared with MH 63.     

甜菜夜蛾对氯虫苯甲酰胺抗性种群选育及鱼尼丁受体基因表达特征

为明确甜菜夜蛾Spodoptera exigua对氯虫苯甲酰胺的抗性发展及抗性种群中鱼尼丁受体(ryanodine receptor,RyR)基因的表达量变化,室内采用饲料混毒法进行甜菜夜蛾对氯虫苯甲酰胺的抗性选育,荧光定量PCR技术研究了抗性和敏感种群之间RyR基因mRNA表达量的差异。结果表明,室内选育31代后获得一个抗性倍数为105.60倍的甜菜夜蛾抗性种群,其mRNA表达量在甜菜夜蛾不同发育阶段及抗性种群和敏感种群之间均存在差异,以表达量最低的卵期作为对照,抗性种群中1龄幼虫表达量最高,是卵期的154.58倍;其次是雄性成虫,其表达量是卵期的101.51倍;2~5龄幼虫分别是卵期的59.56、35.35、72.99和19.84倍。抗性种群中1、2和4龄幼虫mRNA表达量分别是敏感种群的5.99、2.79和2.14倍,其余阶段低于敏感种群。表明甜菜夜蛾对氯虫苯甲酰胺的抗药性可能主要表现在幼虫阶段,RyR基因的表达量变化与氯虫苯甲酰胺诱导有关。