Effect of rhizosphere microorganisms on aflatoxin contamination of maize

Heliyon. 2023 Apr 29;9(5):e15949. doi: 10.1016/j.heliyon.2023.e15949. eCollection 2023 May.

Abstract

The continued large consumption of maize makes it one of the most important food crops worldwide. However, the yield and quality of maize are greatly affected by global warming, and mycotoxin pollution keeps increasing. The effect of environmental factors, especially rhizosphere microorganisms, on mycotoxin pollution of maize is not completely clear, so we carried out relevant studies. In this study, we found that microbial communities inhabiting the maize rhizosphere, which consists of soil particles firmly attached to roots, as well as the soil, have a significant influence on the aflatoxin pollution of maize. The ecoregion and soil properties also had considerable effects on the microbial structure and diversity. The bacterial communities from the rhizosphere soil were profiled using a high-throughput next-generation sequencing method. The ecoregion and soil properties had considerable effects on the microbial structure and diversity. A comparison of the aflatoxin high concentration group with the low concentration group found that bacteria of the phylum Gemmatimonadetes and order Burkholderiales were significantly more abundant in the high concentration samples. Furthermore, these bacteria were significantly correlated with aflatoxin contamination and could aggravate its contamination of maize. The results of these analyses showed that seeding location could cause significant shifts in the root microbiota of maize, and the bacteria enriched in high aflatoxin contamination area soils should attract special concern. These findings will support strategies for improving maize yield and aflatoxin contamination control.

Keywords: Aflatoxin contamination; Correlation analysis; Maize; Microbiota; Soil physicochemical properties.