Transgenic Bt Cotton: Effects on Target and Non-Target Insect Diversity

Abstract

Occurrence of diversity in ecosystem sustains particular characteristic of a biological community and also ensures stability of the community. Transgenic crops may affect insect biodiversity by unintended impacts on non-target arthropod population. For example, transgenic GM cotton specific to target lepidopterous pests can change the cotton pest spectrum and may induce the growth of new harmful pest species having no pest status. The change in species composition may influence IPM approach in cotton crop. The results of authors' research studies as well as global impact indicate that GM cotton is highly specific to target pests and has no unintended impact on non-target insect population. GM cotton provides significant season-long field control of target pests (Helicoverpa armigera, Earias spp. and Pectinophora gossypiella), with no significant control of Spodoptera species. The decreased insecticide use in GM cotton has a positive impact on beneficial insect populations and can increase the stability of rare species. Bt cotton has no resistance against non-target sucking insect pests. As GM cotton has no adverse effects on the non-target insect population and can reduce the use of broad-spectrum insecticides, it can become an important tool of IPM program in cotton agro-ecosystem of Pakistan.

Impact of genetically modified crops on rhizosphere microorganisms and processes: A review focusing on Bt cotton

“…with >500 insects showing resistance to various pesticides commonly used in agricultural practice (Andow, 2008). Thus, the cultivation of GM Bt crops is advantageous because it can reduce the use of broad-spectrum insecticides and also protect non-target insect diversity (Arshad et al, 2018).…”

Progress and perspective on cotton breeding in Pakistan

“…The Bt toxin has increased resistance to major pests in cotton, and has significantly reduced pesticide applications, and has generated high quality cotton. The utilization of transgenic Bt cotton material introduced pest resistant trait into high yielding varieties in Pakistan (Arshad et al 2018). Several Bt cotton varieties were then approved for the maintenance of economic growth of textile sector.…”

“…World cotton production has been significantly decreased in the last decade. As expected, sustainable cotton production in Pakistan is limited due to the climate change, unavailability of the quality seed, less genetic diversity, stresses caused by whitefly infestation and cotton leaf curl virus disease, frequent pink bollworm attacks, unstandardized procedure of variety approval, food crops competition, weed crop competition, and instability of output/input prices (Bakhsh et al 2005;Masood et al 2011;Ali et al 2015;Arshad et al 2018;Ashraf et al 2018;Shuli et al 2018;Abbas 2020;Razzaq et al 2021). Researchers along with breeding community are working hard to reduce recent yield decline of cotton.…”

Effect of Different Spacing of Bt and Non Bt Cotton Hybrid on Population of P. gossypiella under High Density Planting

“…The causes for its low productivity compared to national level can be attributed to various problems [4]. Menace caused by the insect pests is a major one.…”