Effect of transgenic cotton continuous cropping on soil bacterial community

Abstract

Abstract Purpose In agricultural practices, continuous cultivation of genetically modified crops with high commercial value has a definite impact on soil microbial diversity. Soil microorganisms directly define the operational degree and function realization of the soil ecosystem. To understand the safety of environmental release, we studied the effects of continuous cropping of transgenic cotton on the diversity of bacterial communities in the rhizosphere soil. Methods We have applied a high-throughput sequencing method and compared the bacterial community structure as well as diversity of rhizosphere soil of the transgenic cotton line (25C-1) and its parent cotton line (TH2). Result Structural analysis of the bacterial community showed that Arthrobacter and Sphingomonas are significantly enriched after continuous cropping of transgenic cotton lines and had a positive impact on the soil’s ecological environment. Interestingly, parameters of the physical and chemical properties of soil used for the continuous cropping of the two cotton lines for 3 consecutive years show no detectable change, other than total nitrogen. Notably, Spearman’s correlation analysis suggests that total nitrogen is the key environmental factor that affects the bacterial community of the soil used to cultivate the transgenic cotton. Conclusion We did not find a notable difference in species diversity between the two samples. However, the proportions of beneficial bacteria (Arthrobacter and Sphingomonas) increased and the total nitrogen content has changed in 3 years. These results provide necessary insights into the function and role of bacteria in transgenic cotton. This study will help future investigators assess the potential ecological risks of genetically modified plants.