The Interactive Effect of Cover Crop Diversity and Tillage Type on Grain Corn Yield (Zea mays L.) on a Sandy Loam Soil in Southwestern Ontario

Abstract

Best management practices such as cover crops (CC) and reduced tillage can replenish and protect soil, yet the magnitude of their interactive effects are largely unknown. This study evaluates the effects of tillage types (no-tillage, strip-tillage, and bio-tillage) and CC diversity on corn grain yield in a temperate, humid climate. Hairy vetch (Vicia villosa) and HV+rye (Secale cereale L.) showed the highest yields, with HV comparable to noCC+180 kg N ha⁻¹. Generally, HV outperformed pea, in terms of corn yield, and penalties associated with rye were offset in bi- and polycultures. Fall CC biomass was related to species diversity but was better explained by lifecycle (i.e., winter killed > overwintering). Strip-tillage improved yields by ~0.4 Mg ha⁻¹ compared to no-till and bio-tillage. Although no interaction between tillage*CC was observed, bio-tillage shows promise in Ontario, offering comparable yields to no-till while potentially enhancing soil health and reducing fuel and labor costs.Grain Farmers of OntarioOntario Ministry of Farming, Agriculture and Agribusiness and Ministry of Rural Affair