Response of Snap Beans to Tillage and Cover Crop Combinations

Abstract

Abstract Field experiments were conducted on a Norfolk loamy sand (fine-loamy, siliceous, thermic Typic Paleudult) from 1983 through 1985 to determine the effects of tillage method, cover crop, and N fertilization on inorganic soil N and yield, yield components, and N content of snap bean (Phaseolus vulgaris L.). Hairy vetch (Vicia villosa Roth), hairy vetch plus wheat (Triticum aestivum L.), Austrian winter pea (Pisum sativum ssp. arvense L. Poir), Austrian winter pea plus wheat, wheat, crimson clover (Trifolium incarnatum L.) and no cover were the cover crop treatments. Inorganic N concentrations generally were greater in soil with cover crop treatments containing legumes than in soil with no cover and wheat treatments. The use of Austrian winter pea, hairy vetch, and crimson clover as cover crops without supplemental N resulted in snap bean yields comparable to those obtained when 90 kg·ha−1 additional N was supplied. Supplemental N decreased the amount of dry matter partitioned into pods. Inorganic N profiles in the soil indicated that conventional tillage (CT) practices resulted in greater mineralization of N fixed by the legume cover crops than no-tillage (NT) practices. However, snap bean yields for NT were comparable to or greater than those obtained with CT, suggesting that N released from legume residues provided sufficient supplemental N for optimum growth and yield.