ARS | Publication request: CROP PRODUCTION IN A WHEAT-COTTON DOUBLE CROP ROTATION WITH CONSERVATION TILLAGE

Submitted to: Journal of Production Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 1, 1997
Publication Date: N/A

Interpretive Summary: Eradication of the boll weevil has allowed cotton to be produced more economically in the eastern Coastal Plain, and there has been a large increase in the cotton acreage in this area. Conservation tillage has also allowed cotton to be produced with less soil erosion, particularly if substantial crop residues can be produced in a crop rotation. The long growing season of the Cotton Belt allows the production of significant quantities of crop residues from two crops grown in one year, and conservation tillage allows conservation of moisture and quicker planting of cotton after wheat. Therefore, from 1988 to 1994, we investigated double-cropped wheat-cotton on plots located near Florence, SC, that had been in continuous conservation versus conventional tillage since 1979. Five of the seven years had > 145 frost-free days, and cotton yields were better for conservation tillage than conventional tillage. 'Delta Pine 20' was the earliest cultivar tested, and it had the best seed cotton yields. However, two years had crop failure because of early freezes. Thus, development of earlier maturing cotton and wheat cultivars will be important for this cropping system in the northern portion of the cotton growing areas of the Coastal Plain.

Technical Abstract: The long growing season of the Cotton Belt allows the production of two crops in one year, and conservation tillage allows conservation of moisture and quicker planting after wheat. Therefore, from 1988 to 1994, we investigated double-cropped wheat-cotton on plots that had been in continuous conservation versus conventional tillage since 1979. The experimental site was located near Florence, SC, on a Norfolk loamy sand Typic Kandiudult). Conventional tillage consisted of multiple diskings and cultivations; surface tillage was eliminated for conservation tillage. Cotton planting dates ranged from June 7 to 18. Five of the seven years had > 145 frost-free days, and seed cotton yields ranged from 2.45 to 0.56 Mg/ha for conservation tillage cotton. Seed cotton yields ranged from 2.10 to 0.35 Mg/ha for conventional tillage cotton. 'Delta Pine 20' was the earliest cultivar tested, and it had the best seed cotton yields with means of 1.74 and 1.43 Mg/ha for conservation and conventional tillage, respectively. However, two years had crop failure because of early freezes, and a June drought prevented the planting of cotton in one year. Thus, development of earlier maturing cotton and wheat cultivars will be important for this cropping system in the northern portion of the cotton growing areas of the Coastal Plain.