Two-year field studies during Kharif 2015 and 2016 were conducted to assess the abundance and diversity of arthropod communities of Bt cotton carrying Cry1Ac and Cry2Ab proteins and non-Bt cotton under sprayed and unsprayed conditions. The experiment was conducted in a randomized block design with four treatments of BG-II and non-Bt cotton. The treatments were non- transgenic cotton with no insecticide treatment, non-transgenic cotton with insecticide treatment, transgenic cotton with no insecticide treatment and transgenic cotton with an insecticide treatment. Arthropod community categorized as target insect pests, sucking insect pests, natural enemies and non-target insects were recorded at different phases of the cotton crop. The sucking insect pests contributed the highest abundance among the total arthropods recorded during the period of study. The abundance and diversity of bollworms that were recorded from non-Bt cotton only suggested effectiveness of BG II cotton against target insect pests. The abundance, species richness and diversity indices with respect to populations of beneficial predaceous arthropods and non-target insects were similar in BG-II and its non-Bt counterpart under unsprayed conditions. On the contrary, these parameters were significantly on the lower side under sprayed regimes for both genotypes. The spray of insecticides in early season against sucking insect pests significantly reduced their abundance and diversity indices in both BGII and non-Bt cotton. As monocropping of BG-II cotton is common on large parts of India, there is a need to monitor the populations of non-target insect species with special emphasis on sucking insect pests on a continuous basis to understand the long-term impact of Bt crops on insect biodiversity for sustainable integrated pest management practices.

中文翻译：

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印度条件下转基因 Bt 和非 Bt 棉田节肢动物的丰度和多样性

在 2015 年和 2016 年 Kharif 期间进行了为期两年的实地研究，以评估在喷洒和未喷洒条件下携带 Cry1Ac 和 Cry2Ab 蛋白的 Bt 棉花和非 Bt 棉花节肢动物群落的丰度和多样性。该实验采用随机区组设计，对 BG-II 和非 Bt 棉花进行四次处理。处理为未杀虫剂处理的非转基因棉花、杀虫剂处理的非转基因棉花、未杀虫剂处理的转基因棉花和杀虫剂处理的转基因棉花。在棉花作物的不同阶段记录了分为目标害虫、吸食性害虫、天敌和非目标昆虫的节肢动物群落。在研究期间记录的所有节肢动物中，吸吮害虫的丰度最高。从非 Bt 棉花中记录的棉铃虫的丰度和多样性仅表明 BG II 棉花对目标害虫的有效性。在未喷洒条件下，BG-II 及其非 Bt 对应物的有益捕食性节肢动物和非目标昆虫种群的丰度、物种丰富度和多样性指数相似。相反，这些参数在两种基因型的喷洒方案下都显着偏低。早季喷洒杀虫剂防治吮吸性害虫，显着降低了 BGII 和非 Bt 棉花的丰度和多样性指数。由于 BG-II 棉花的单作在印度大部分地区很常见，