Insecticidal proteins from the Bacillus thuringiensis (Bt) marks the genetically modified cotton crop that was commercialized in India in March 2002 for the control of lepidopteron bollworms. Despite organized initial control, the pink bollworm (PBW), Pectinophora gossypiella (Saunders), adapted itself to cry toxins resulted in field control failures in 2016 and 2017. The present study was designed to understand the survival and development of PBW populations differing in susceptibility to Cry toxins on Bt and non-Bt plants. For assessment of infestation, populations were collected from different cotton growing states. Per cent infestation of flowers and green bolls in the study areas were in the range of 3.09–29.26 and 36–91.20% for flowers and green bolls, respectively. Among different locations highest magnitude of resistance to Cry1Ac (371.8-fold) and Cry2Ab (4214.3-fold) was spotted in late season populations of Rajkot collected from bolls. Further, in order to confirm field level resistance of surviving larvae on high and low concentrations of Cry toxins, larvae were pooled and subjected to boll bioassays. Results revealed that, none of the larvae from susceptible populations survived on BGII bolls. Although, the same populations showed a survival of 38 and 32%, which led to 80% locule damage on non-Bt cotton. Maximum survival (32%) and locule damage (70%) was observed for Maharashtra (F-H) Cry2Ab and Gujarat (B-H) Cry2Ab populations recorded 36% survival and 70% mortality, respectively, on BGII cotton and 58.33% survival and 60% locule damage on non-Bt cotton, respectively. Populations derived from survivals on low concentrations produced the lowest survival and locule damage on Bt cotton. Maximum number of mines on epicarp (2.4 mines/boll) was recorded by susceptible population on NBt cotton. Green bolls of Bt and NBt cotton did not differ in the number of mines. It was concluded that none of the larvae from susceptible populations survived on BGII bolls. Although, the same populations showed a survival of 38 and 32%, which led to 80% locule damage on non-Bt cotton

中文翻译：

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印度棉铃虫，棉铃虫（桑德斯）（鳞翅目：s科）在转基因棉花上的生存

苏云金芽胞杆菌（Bt）的杀虫蛋白标志着转基因的棉农作物，该农作物于2002年3月在印度商品化，用于控制鳞翅目棉铃虫。尽管进行了有组织的初步控制，但粉红色棉铃虫（PBW），棉桃菌（Saunders）在2016年和2017年适应了哭泣毒素，导致田间控制失败。本研究旨在了解易感性不同的PBW种群的生存和发展。在Bt和非Bt植物上哭泣的毒素。为了评估侵染，从不同的棉花生长州收集种群。在研究区域内，花和绿铃的侵染百分比分别为3.09–29.26和36–91.20％。在不同位置之间，对Cry1Ac的抗性最高（371。8倍）和Cry2Ab（4214.3倍）存在于从棉铃收集的Rajkot的后期种群中。此外，为了确认存活的幼虫对高和低浓度的Cry毒素的田间水平抗性，将幼虫合并并进行铃虫生物测定。结果显示，来自易感种群的幼虫均未在BGII棉铃上存活。虽然，相同种群的存活率分别为38％和32％，这导致非Bt棉花对子房的伤害达到80％。马哈拉施特拉邦（FH）Cry2Ab和古吉拉特邦（BH）的Cry2Ab种群在BGII棉花上分别达到36％的存活率和70％的死亡率以及58.33％的存活率和60％的肾小管的最大存活率（32％）和对子房的损害（70％）。分别对非转基因棉花造成损害。低浓度存活的种群对Bt棉的存活和对子房的伤害最低。NBt棉花上的易感种群记录了果皮上最大的地雷数量（2.4枚/铃）。Bt和NBt棉的绿色棉铃在地雷数量上没有差异。结论是，来自易感种群的幼虫都没有在BGII棉铃上存活。虽然，相同种群的存活率分别为38％和32％，这导致非Bt棉花的子房受损80％