Submitted to: Annual Southern Conservation Tillage Conference for Sustainable Agriculture
Publication Type: Proceedings
Publication Acceptance Date: June 10, 2002
Publication Date: June 24, 2002
Citation: Locke, M.A., Zablotowicz, R.M., Steinriede Jr, R.W., Dabney, S.M. 2002. CONSERVATION MANAGEMENT PRACTICES IN MISSISSIPPI DELTA AGRICULTURE: IMPLICATIONS FOR CROP PROTECTION AND ENVIRONMENTAL QUALITY. In: Making Conservation Tillage Conventional: Building a Future on 25 Years of Research, E. van Santen (Ed.). Proc. 25th Southern Conservation Tillage Conference, Auburn, AL, pp. 320-326. Interpretive Summary: Conservation management systems such as reduced tillage and cover crops may provide farmers with opportunities to reduce overall production costs while addressing environmental concerns. Research is needed to critically evaluate these systems to develop sound recommendations for farmers. A two-year study was conducted on a no-till farm in the Mississippi Delta to evaluate changes in soil quality, weed management, and cotton lint yield as a result of utilizing clover as a winter cover crop. Establishment of the cover crop improved soil microbiological characteristics, nitrogen availability, and weed control, but had only marginal effects on lint yield and likely had no economic benefit. These results provide important information for farmers to make decisions on whether to add legume cover crops as a component of their management system.
Technical Abstract: For wider acceptance of conservation management systems, e.g., reduced tillage and cover crops, experimental information is needed to guide growers in implementing these systems and also to critically evaluate environmental impacts. This paper summarizes a series of laboratory and field experiments assessing the effects of conservation management on soil properties, herbicide fate, weed control and yield. Adoption of conservation management practices alters organic matter distribution, especially in the soil surface. Enhanced organic matter typically increases microbial activity and often increases the capacity of the soil to sorb herbicides. Increased herbicide retention and microbial activity affect the degradation of herbicides and bioavailability for weed control. Results from an on-farm study showed that balansa clover (Trifolium balansae) was successfully established in a cotton (Gossypium hirsutum L.) production field, altered certain indices of soil quality (e.g., microbiological indicators, N availability), and provided some weed control and slight yield benefit. However, the economics of using legume cover crops such as balansa clover in cotton is in question and needs more critical evaluation over several additional years of study and multiple sites.