Location: Soil Dynamics ResearchTitle: Cover crop mixtures for cotton production
|DELANEY, DENNIS - Auburn University|
|FENG, YUCHENG - Auburn University|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 9/3/2019
Publication Date: 11/13/2019
Citation: Balkcom, K.S., Delaney, D.P., Feng, Y. 2019. Cover crop mixtures for cotton production[abstract]. ASA-CSSA-SSSA Annual Meeting. CD ROM.
Technical Abstract: Benefits associated with conservation tillage and single species cover crops have been documented across the Southeast, but cover crop mixtures should be compared to traditional single species used in the Southeast to verify if benefits exist under Southeast growing conditions. We examined how two cover crop mixtures of rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) (Mix 1 - 34 kg/ha rye and 11 kg/ha vetch; Mix 2 - 34 kg/ha rye and 22 kg/ha vetch) affected early season cotton (Gossypium hirsutum L.) growth and lint yield compared to fallow and single species cover crops of rye (101 kg/ha) fertilized with 34 kg N/ha or hairy vetch (22 kg/ha). The five main plot cover crop treatments were arranged in a randomized complete block design with four blocks with a split-plot treatment restriction that consisted of four sidedress nitrogen rates (0, 67, 101, and 134 kg/ha) across five site-years in Alabama. Vetch produced the least biomass four out of five site-years and averaged 29% less biomass than either mixture or rye. Mix 1 and Mix 2 produced equivalent biomass (5615 kg/ha) across all five site-years, while rye averaged 5833 kg/ha. The legume covers (Vetch, Mix 2, and Mix 1) consistently produced the greatest early season cotton growth followed by rye compared to fallow. Cotton lint yields were only collected for three site-years, but a cover crop X N rate interaction, observed two out of three years, indicated fallow and rye that received no sidedress N produced the lowest yields. A sidedress N rate of 67 kg/ha maximized lint yield two out of three years with 101 kg N/ha required the remaining year. Preliminary results indicate rye/vetch mixtures performance was equivalent or superior to single species cover crops and fallow in a cotton production system.