Abstract The current investigation was conducted to estimate the resistance level against deltamethrin in fourth and sixth instar larvae of Trogoderma granarium collected from wheat storage warehouses of Dera Ghazi Khan (DGK), Okara (OKR) and Gujranwala (GUW). Results showed that the fourth and sixth instar larvae of collected strains warehouses moderately resistant to deltamethrin compared with the same developmental stages of insecticide susceptible laboratory strain (LAB-S). Efficacies of bifenthrin, chlorpyrifos and their various combinations were analyzed against fourth and sixth instar larvae of different strains of pest populations to minimize the development of resistance against deltamethrin. LC50s of bifenthrin against fourth and sixth instar larvae of all the four populations were recorded at low concentrations compared to deltamethrin. The LC50 values of bifenthrin against fourth instar larvae of LAB-S, DGK, OKR and GUW populations were 359.32, 416.58, 524.01 and 598.91 ppm, respectively, while these values were 204.30, 262.98, 301.89 and 355.22 ppm against sixth instar larvae of those populations, respectively. Chlorpyrifos was found to be the most effective insecticide compared to bifenthrin and deltamethrin. The LC50 values of chlorpyrifos were 189.33, 305.37, 376.30 and 459.15 ppm against fourth instar larvae of LAB-S, DGK, OKR and GUW populations, respectively, whereas for sixth instar larvae those values were 98.24, 129.61, 163.43 and 230.74 ppm, respectively. Various combinations of bifenthrin and chlorpyrifos viz., 1:1, 2:1, 3:1, 1:2 and 1:3 were also tested. Based on the values of LC50 and relative toxic unit, 1:3 combination was observed as the most effective among all combinations. The LC50 values of fourth instar larvae of all the four populations against each insecticide and their combinations were recorded at high concentration compared to that of sixth instar larvae. Results of current investigation need to be considered in present stored grain insect pest control program of warehouses in Punjab1.

中文翻译：

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储粮害虫Trogoderma granarium (Everts)对溴氰菊酯的抗性发展及其联苯菊酯和毒死蜱协同毒害的有效防治

摘要 本研究旨在评估从Dera Ghazi Khan (DGK)、Okara (OKR) 和Gujranwala (GUW) 小麦储藏仓库收集的Trogoderma granarium 4 龄和6 龄幼虫对溴氰菊酯的抗性水平。结果表明，与相同发育阶段的杀虫剂敏感实验室菌株（LAB-S）相比，所收集菌株的四龄和六龄幼虫对溴氰菊酯具有中等抗性。分析了联苯菊酯、毒死蜱及其各种组合对不同害虫种群的四龄和六龄幼虫的功效，以尽量减少对溴氰菊酯的抗性的发展。与溴氰菊酯相比，联苯菊酯对所有四个种群的四龄和六龄幼虫的 LC50 在低浓度下被记录。联苯菊酯对LAB-S、DGK、OKR和GUW群体四龄幼虫的LC50值分别为359.32、416.58、524.01和598.91 ppm，而对六龄幼虫的LC50值分别为204.30、262.98、2315 ppm和2315ppm。人口，分别。与联苯菊酯和溴氰菊酯相比，毒死蜱被发现是最有效的杀虫剂。毒死蜱对LAB-S、DGK、OKR和GUW群体四龄幼虫的LC50值分别为189.33、305.37、376.30和459.15 ppm，而对于六龄幼虫的LC50值分别为98.24、376.30和459.15 ppm，分别为98.24、376.30和459.16 . 还测试了联苯菊酯和毒死蜱的各种组合，即 1:1、2:1、3:1、1:2 和 1:3。根据 LC50 和相对毒性单位的值，1：3 种组合被认为是所有组合中最有效的。与六龄幼虫相比，所有四个种群的四龄幼虫对每种杀虫剂及其组合的 LC50 值均以高浓度记录。目前的调查结果需要在旁遮普省仓库的现有储粮害虫控制计划中加以考虑1。