SiO2@CuO Nanozyme Reinforces Plant-Microbiome Synergies for Simultaneous Yield Enhancement, Nutritional Fortification, and a Beneficial Soil Legacy

Abstract

Plant associated microbes play pivotal role in promoting host fitness and health. However, modern agricultural practices, such as agrochemicals use and domestication are eroding plant-microbe partnership. Here, we show that nanoenabled seed priming strengthens plant-microbe interactions, enhancing the plant holobiont performance. We found that SiO2@CuO nanozymes (NZs) with peroxidase (POD)-like activities, as seed priming agent, initiate earlier and stronger seed respiration and boost exudates release (sugars, amino acids, and fatty acids), creating a nutrient-rich and transiently hypoxic spermosphere microenvironment. Field trials revealed that by day 40, rhizosphere microbiome diversity increased, with enrichment of functional taxa involved in carbon and nitrogen metabolism, as determined by 16S rRNA and metagenomic sequencing. Throughout the growing season, above-ground tissues in the nanopriming group consistently outperformed the hydropriming control in photosynthetic pigment content and plant height. At harvest, without additional fertilizers or other inputs, nanopriming increased maize yield by 8.1% and improved kernel nutritional quality: starch (21.0%), protein (24.5%), and iron (24.2%). Soil nutrient availability (N, P, K, Ca) and cation exchange capacity also increased, indicating the improved soil quality. Notably, the soil from nanopriming group confers the subsequent maize crop with better drought tolerance and enhanced P uptake capacity, compared to the soil from hydropriming group, indicating beneficial legacy effect. This study demonstrates that a simple seed nanopriming can steer a positive feedback loop between plant and microbe, cascading into multifaceted holobiont benefits. This offers a sustainable strategy to harness plant microbiomes and promote sustainable and climate resilient agriculture.