Genetically Modified Sugarcane Intercropping Soybean Impact on Rhizosphere Bacterial Communities and Co-occurrence Patterns

Abstract

Strategies involving genes in the dehydration-responsive element binding (DREB) family, which participates in drought stress regulation, and intercropping with legumes are becoming prominent options in promoting sustainable sugarcane cultivation. An increasing number of studies focusing on root interactions in intercropping systems, particularly involving transgenic crops, are being conducted to better understand and thus, harness beneficial soil microbes to enhance plant growth. We designed experiments to investigate the characteristics of two intercropping patterns, soybean with wild-type (WT) sugarcane and soybean with genetically modified (GM) Ea-DREB2B-overexpressing sugarcane, to assess the response of the rhizosphere microbiota to the different cropping patterns. Bacterial diversity in the rhizosphere microbial community differed between the two intercropping pattens. In addition, the biomass of GM sugarcane that intercropped with soybean was significantly improved compared with WT sugarcane, and the aboveground biomass and root biomass of GM soybean intercropping sugarcane increased by 49.15 and 46.03% compared with monoculture. Furthermore, a beneficial rhizosphere environment for the growth of Actinobacteria was established in the systems intercropped with GM sugarcane. Improving the production mode of crops by genetic modification is a key strategy to improving crop yields and provides new opportunities to further investigate the effects of intercropping on plant roots and soil microbiota. Thus, this study provides a basis for selecting suitable sugarcane–soybean intercropping patterns and a theoretical foundation for a sustainable sugarcane production.

Maize intercropping enriches plant growth-promoting rhizobacteria and promotes both the growth and volatile oil concentration of Atractylodes lancea

“…The relative abundance of the rhizosphere microorganism Acidobacteria in A. lancea under both the AI and AN treatment was higher than that in CK treatment ( Figures S1A, E ). Changing the soil microenvironment in the plant rhizosphere is known to be conducive to soil nutrient cycling ( Kielak et al., 2016 ), thereby effectively improving the uptake of nitrogen (N), phosphorus (P), kalium (K), and other elements in the soil by plants, which is beneficial to their growth and development ( Zeng et al., 2020 ; Wei et al., 2021 ). From the correlation analysis of Figure 7A , we observe that TP, TOC, Av.P, and Av.K were significantly positively correlated with the abundance of the majority of the different A. lancea rhizosphere microorganisms (the top 30 species), which was consistent with our Figures 6A-C analysis, where the relative abundance of these genera under the CK treatment was higher.…”