The agronomic and economic viability of innovative cropping systems to reduce Fusarium head blight and related mycotoxins in wheat

Abstract

Abstract CONTEXT The effective control of Fusarium head blight (FHB) in wheat, mainly caused by the toxigenic fungus Fusarium graminearum, has a significant impact on food safety worldwide. As maize is one of the main hosts of F. graminearum, the risk of infection by this plant pathogen is highest when wheat is grown after maize and infected crop residues are not buried through ploughing. OBJECTIVES This study aimed to investigate the agronomic and economic viability of two innovative cropping systems with the goal to reduce the risk of FHB and mycotoxins in subsequent wheat. These systems were maize-intercropping and cover cropping with different plant species before the wheat growing season under reduced tillage practices. METHODS For the maize-intercropping study, red clover, sudangrass, phacelia, white mustard and Indian mustard were used as intercrops with grain maize and compared with a sole maize crop in a grain maize-winter wheat rotation under no-tillage or reduced tillage. For the cover cropping study, white mustard, Indian mustard and winter pea were used as interval cover crops in a silage maize-spring wheat rotation under no-tillage and compared with treatments without a cover crop, i.e. herbicide or plough applied after silage maize. The incidence of Fusarium head blight causing species and the accumulation of mycotoxins in grains of wheat as well as the crop yield were monitored. In addition, an economic assessment was conducted by calculating the receipts, operating costs and gross margin for each cropping system. RESULTS AND CONCLUSIONS Growing intercrops with maize or interval cover crops in a maize-wheat rotation under reduced tillage decreased mycotoxins in wheat while maintaining wheat yield. The use of white mustard or Indian mustard as intercrops reduced deoxynivalenol in winter wheat by up to 52% compared with maize grown as a sole crop. The use of white mustard, Indian mustard or winter pea as interval cover crops also reduced deoxynivalenol and improved yield in spring wheat by up to 85% and 25%, respectively. Remarkably, the toxin reduction through these cover crops was comparable with that obtained by ploughing. However, due to increased operating costs, we observed economic trade-offs in these innovative cropping systems, i.e. 7–25% reduced gross margin over the entire rotation. SIGNIFICANCE Both cereal growers and consumers can benefit from the recommended practices, which considerably lower the risk of mycotoxin contamination in harvest products while maintaining crop yield. To address the economic trade-offs, policy makers should support innovation in cropping systems, enhancing food safety while also ensuring the economic viability of cereal production systems.