Impact of Transgenic Cry1Ab/2Aj Maize on Abundance of Non-Target Arthropods in the Field

Abstract

Transgenic <i>Bacillus thuringiensis</i> (<i>Bt</i>) maize has broad prospects for application in China. Before commercialization, it is necessary to assess possible ecological impacts, including impacts on non-target arthropods (NTAs) in the field. In the present study, transgenic <i>Bt</i> maize expressing <i>cry1Ab/2Aj</i> and its corresponding non-transformed near isoline were planted under the same environmental and agricultural conditions, and arthropods in the field were collected during the three main growth stages of maize. In a one year trial, the results showed the composition of NTA communities in the transgenic and control maize fields were similar. There were no significant differences for community-level parameters of species richness (<i>S</i>), Shannon-Wiener diversity index (<i>H'</i>), evenness index (<i>J</i>) and Simpson's dominant concentration (<i>C</i>) between the two types of maize fields. Likewise, a Bray-Curtis dissimilarity and distance analysis showed that Cry1Ab/2Aj toxin exposure did not increase community dissimilarities between <i>Bt</i> and non-<i>Bt</i> maize plots and that the structure of the NTAs community was similar on the two maize varieties. Furthermore, planting of the transgenic <i>cry1Ab/2Aj</i> maize did not affect the density or composition of non-target decomposers, herbivores, predators, parasitoids and pollinator guilds. In summary, our results showed that planting of <i>Bt</i> maize producing Cry1Ab/Cry2Aj proteins do not adversely affect population dynamics and diversity of NTAs.