Amomum Villosum Lour. Fruits Grown in Metal-Polluted Soils Pose No Health Risk to Humans And Soil Microorganisms Play a Regulatory Role in Them

Amomum villosum Lour. fruit is a common health food that is widely cultivated in southern China. In recent years, heavy metal contamination in farmland soil has been a serious environmental issue in China. The accumulation of heavy metals in soil can be introduced to the food chain and cause health risks for humans. Besides, microbial communities are reported to play a beneficial role in plant grown in metal-polluted soils. This study aimed to assess the potential health risks of heavy metals in plantation soils and A. villosum fruits from different producing areas and explore the soil-microbe-plant regulation pattern for heavy metals in A. villosum fruits. We collected the soil and A. villosum fruit samples from nine planting fields in four provinces of southern China. Results showed that the soil samples in seven out of nine areas were polluted by heavy metals to different degrees. As, Cr and Mn were the most serious contaminated elements in A. villosum farmland soils. However, the accumulation of heavy metals in A. villosum fruits was weak, and the human health risks caused by heavy metals in all A. villosum fruit samples were acceptable. Partial least squares path analysis of structural equation modeling (PLS-SEM) revealed that the contents of heavy metals in A. villosum fruits were affected indirectly by soil heavy metals through the regulation of microbial community. Furthermore, some fungal phyla (e.g., Ascomycota and Chytridiomycota) and genera (e.g., Mucor) were found to be related to the contents of heavy metals in soil and the accumulation of heavy metals in A. villosum fruits. The results of this study will help to explore the potential fungi that can tolerate heavy metal pollution in soil and mitigate heavy metal accumulation in plants, and ultimately reduce the health risk posed by heavy metals in food.