Reduced tillage agriculture may improve plant nutritional quality through increased mycorrhizal colonization and uptake of the antioxidant ergothioneine

Many farmers have adopted reduced tillage management practices. While the effectiveness of these practices at reducing soil erosion and enhancing soil health are well documented, the impact of reduced tillage on plant nutritional quality is not well understood. Current interest in the role of the fungal derived antioxidant ergothioneine (ERGO) in human health has driven efforts to understand the influence of different crop management practices on the transfer of ERGO from soil to plants and ultimately to human consumption. We sampled roots and plant tissue from soybeans (Glycine max) and wheat (Triticum aestivum) in a long-term (40+ year) side-by-side tillage trial and examined the extent to which moldboard plow (high intensity tillage), chisel/disk (intermediate tillage), and no-till (minimal disturbance) practices affected mycorrhizal colonization, ERGO concentration, mineral nutrient concentration, and yield. We found that high tillage intensity reduced the ERGO concentration of wheat grain by about half. The ERGO concentration of wheat was positively correlated with percent mycorrhizal colonization. Additional benefits of reduced tillage were increased concentration of soybean P, Mg, Cu, Zn, and increased soybean yield. These results demonstrate a possible link between soil health and human health through positive mycorrhizal influence on plant ERGO uptake.