Intercropping and Nano Zinc Oxide Application Enhance Plant Resistance and Alleviate Pesticide Stress by Altering the Soil Microenvironment

Pesticide stress significantly reduces crop productivity. This study investigated wheat-fava bean intercropping combined with nano zinc oxide (nZnO) application as a strategy to alleviate pyroxasulfone (PYR) stress on fava beans. We examined the effect on plant growth, the rhizosphere microenvironment, and PYR degradation. The combined treatment effectively reduced the PYR toxicity and promoted fava bean growth. It enhanced plant antioxidant enzyme activities and soil nutrient cycling enzymes, leading to increased PYR degradation and decreased number of soil PYR residues. Furthermore, these treatments stimulated the secretion of rhizosphere flavonoids and organic acids, enriching beneficial bacterial communities, specifically Sphingomonas, Gemmatimonas, and Streptomyces. Functional predictions using FAPROTAX indicated significant changes in carbon, nitrogen, and sulfur cycling, suggesting a crucial microbial role in accelerating PYR degradation and improving plant resilience. These findings present a promising and sustainable agricultural strategy to mitigate pesticide pressure.