WHEAT AS A COVER CROP IN A NO-TILL COTTON PRODUCTION SYSTEM:THE YALOBUSHA COUNTY EXPERIENCE, 1999-2001

摘要

Cover crops are traditionally defined as crops grown to cover the ground to protect the soil from erosion and from loss ofplant nutrients through leaching and runoff [Reeves]. Researchers often limit their work on cover crops to their impacts onsoil and water quality. No-till (NT) production systems which include adequate winter ground cover have the potential to reducesoil erosion by 90 to 95% of that for conventional tillage (CT), which would satisfy mandated soil loss restriction onmany upland sites used for annual cotton production [Triplett, Dabney, and Siefker].McWhorter and Jordan noted that little of the research designed to develop reduced tillage (RT) and NT systems for cottonwas published because the results were negative and many experiments were abandoned due to loss of weed control and lowyields. In addition, NT has progressive benefits that may not be obvious during the initial year or years of no-till practices[Boquet et al., 1977a]. Cover crops are planted by farmers concerned with economic costs and returns. Frequently their toppriority is economic survival [Dabney, Delgado, and Reeves]. With limited yield data, etc., cover crops became just anotherBMP (best management practice) [Yuan, Dabney, and Binger] and even cost sharing government programs have had littleimpact [Dabney, Yuan, and Binger]. If cover crops are cost effective and growers are provided with the information, growerswill utilize cover crops in their cotton production systems.