Cover Crop and Tillage Effects on Production and Nitrogen Nutrition of Sweet Corn

Abstract

A split-plot factorial experiment examined effects of tillage and winter cover crops on sweet corn. Main plots received tillage or no tillage. Cover crops consisted of hairy vetch, winter rye, or a mix, and N treatments consisted of plus or minus N fertilization. No significant effects of tillage on sweet corn yields were detected. Following corn not receiving inorganic N, vetch produced cover crop total N yields of 130 kg·ha–1 that were over three-times greater than those obtained with rye. Following rye winter covercrops, addition of ammonium nitrate to corn significantly (P < 0.05) increased corn yields and foliar N concentrations compared to treatments not receiving N. However, following vetch, corn yields and foliar N concentrations obtained without N fertilization equaled those obtained with N fertilization following rye or vetch. Available soil N was significantly (P < 0.05) greater following vetch compared to rye for ≈9 weeks after corn planting and peaked ≈4 weeks after planting. It was concluded that no-tillage sweet corn was successful and N fixed by vetch was able to sustain sweet corn production.