Role of Cover Crops in Improving Soil and Row Crop Productivity

TLDR

Cover crops enhance subsequent row crop productivity by improving soil physical, chemical, and biological properties, and are valued for rapid establishment, nitrogen fixation, deep rooting, low C/N residue, and lack of allelopathy, with both leguminous and nonleguminous options available. This review examines recent advances in cover crop practices, evaluating their potential benefits and drawbacks for annual crop production and long‑term soil quality. The authors synthesize current research on cover crop implementation, assessing how different species and management strategies influence soil quality and crop yields. Leguminous cover crops supply substantial biologically fixed nitrogen, decompose readily due to low C/N ratios, and enhance nutrient availability in surface soils, while nonleguminous species exhibit high nitrogen‑scavenging capacity but may be limited by nitrogen deficiency, making grass‑legume mixtures the most effective strategy for maximizing cover crop benefits.

Abstract

Abstract Cover crops play an important role in improving productivity of subsequent row crops by improving soil physical, chemical, and biological properties. The objective of this article is to review recent advances in cover crops practice, in the context of potential benefits and drawbacks for annual crop production and sustained soil quality. Desirable attributes of a cover crop are the ability to establish rapidly under less than ideal conditions, provide sufficient dry matter or soil cover, fix atmospheric nitrogen (N), establish a deep root system to facilitate nutrient uptake from lower soil depths, produce organic matter with low‐residue carbon/nitrogen (C/N) ratio, and absence of phytoxic or allelopathic effects on subsequent crops. Cover crops can be leguminous or nonleguminous. Leguminous cover crops provide a substantial amount of biologically fixed N to the primary crop, as well as ease of decomposition due to their low C/N ratio. Legume cover crops also possess a strong ability to absorb low available nutrients in the soil profile and can help in increasing concentration of plant nutrients in the surface layers of soil. Some nonleguminous cover crops having high N scavenger capacity compared with leguminous crops and sometimes, the growth of these scavenging grass cover crops is limited by N deficiency, growing grass/legume mixtures appears to be the best strategy in obtaining maximum benefits from cover crops.