Tillage and Pest Management Considerations in a Peanut–Cotton Rotation in the Southeastern Coastal Plain

Radical changes in crop production have occurred in the southeastern USA in recent years. Peanut (Arachis hypogaea L.) and cotton (Gossypium hirsutum L.) are now planted in direct rotation, and conservation tillage is commonly used for both crops. Comprehensive data is lacking on crop and pest management recommendations in those systems, so a long-term study was conducted in Tifton, GA on the effects of tillage systems on crop and pest management in a peanut-cotton rotation. Systems evaluated were conventional, reduced, and minimum tillage. Plots in conventional tillage systems were harrowed, deep-turned, and planted each year. In reduced tillage systems, plots were harrowed in the fall and planted to rye (Secale cereale L.), and crops were planted into killed rye. In minimum tillage systems, plots were neither tilled nor planted to rye and remained nontilled during the winter, and crops were planted directly into the previous crop stubble. Weed control was based on species present and tillage system. Peanut was either treated with flutolanil [3'-isopropoxy-2-(trifluoromethyl) benzanilide] for soil-borne disease control or not treated (control). Yields were sustained for 5 yr with no difference in peanut or cotton yields among tillage systems. Flutolanil controlled soil-borne diseases and increased peanut yields, working equally well in all three tillage systems. Weed densities and species composition changed, causing more intensive and costly weed control in reduced and minimum tillage systems than in conventional tillage systems. Spotted wilt (tomato spotted wilt tospovirus) incidence was 42% lower in reduced and minimum tillage systems than in conventional tillage systems and is now part of the recommended strategy to manage the disease.