Impact assessment of genetically modified herbicide-tolerant cotton on arthropod communities

Abstract

BackgroundCotton (Gossypium spp.) is one of the most important economic crops worldwide, and its production plays an important role in the economy of many countries. Genetically modified herbicide-tolerant (GMHT) crops, which were developed to minimize the losses caused by weeds, have gradually become the most widely adopted genetically modified crops in the world due to their economic and environmental benefits. However, the potential ecological and environmental risks of GMHT crops have attracted extensive attention and controversy. Arthropod communities form a prominent part of the biodiversity of agroecosystems and are important indicators of environmental health. Elucidating the effects of GMHT crops on the diversity of arthropod communities is necessary to ensure the safety of GMHT crops.ResultIn this 2-year study, we investigated the potential impact of GMHT crops on arthropod communities. The GMHT cotton variety GGK2 with glyphosate tolerance and its near-isogenic non-GMHT variety K312 were used for the experimental groups. The Shannon diversity index (H), Simpson diversity index (D), Pielou evenness index (J), and principal co-ordinates analysis (PCoA) of the Bray–Curtis distance were used to evaluate the population dynamics and biodiversity of arthropods in cotton fields. No significant differences were found between GGK2 and K312 in their total abundance of arthropod communities, and biodiversity indexes on most sampling dates. The arthropod composition in the GGK2 and K312 plots was similar. Sampling dates had a significant effect on biodiversity indexes, whereas no clear tendencies related to cotton variety or cotton variety × sampling dates interaction were recorded. In addition, PCoA revealed high similarity between the arthropod communities in the plots of the GMHT cotton variety GGK2 and its near-isogenic variety K312.ConclusionThere was no obvious difference in abundance, diversity indexes of arthropod communities between GMHT cotton variety GGK2 and its near-isogenic variety K312 under the small-scale planting regime.