Utilizing Legume Cropping Systems to Reduce Nitrogen Fertilizer Requirements for Conservation‐tilled Corn

Publisher Website
Google Scholar
Abstract
The need to reduce production costs has promoted a renewed interest in using legumes as a source of N for non‐leguminous summer crops. Development of legume cropping systems which will permit reseeding of winter cover‐crop legumes is a promising approach to reducing legume establishment costs. Field studies were conducted in Alabama for 4 yr on Wynnville sandy loam and Dothan fine‐sandy loam soils (fine‐loamy, siliceous, thermic, Glossic Fragiudults and Plinthic Paleudults, respectively) to determine the effects of both cash crop and winter cover‐crop legumes in cropping systems on N fertilizer requirements of corn (Zea mays L.) grown in a conservation‐tillage system. On the Wynnville soil, soybean (Glycine max L. Merr.) was more effective in providing early season N, and clover (Trifolium incarnatum L.) in providing late‐season N. The system with both soybean and clover resulted in an even more effective contribution of N to corn grain yield, and a higher yield level than that of continuous corn regardless of N fertilizer rate. On the Dothan soil, the benefits of cropping systems were not as pronounced, and the responses were eliminated by N fertilization, suggesting increased yields were due to N and not to a rotation effect. On both soils, in years of adequate and inadequate rainfall, the reseeding crimson clover system, in combination with a soybean‐corn rotation, consistently produced the highest yields of the systems studied, and provided a 68 to 159 kg N ha−1 fertilizer equivalent for corn.

This publication has 0 references indexed in Scilit: