Value of Rotational Crops for Profit Increase and Reniform Nematode Suppression with and without a Nematicide in Alabama

                Crop rotation with cotton is often utilized for the suppression of the reniform nematode (Rotylenchulus reniformis) in the southeastern United States. A study was conducted from 2006 – 2009 to evaluate the economic benefit and reniform nematode suppression of single and multiple year rotations of corn, soybeans, and peanuts with cotton, with and without Telone II. All rotations resulted in initial reniform nematode population reductions (P≤ 0.10) compared with continuous cotton. Reduction (P≤ 0.10) of final reniform populations was achieved by cotton following two years of corn, one and two years of peanuts, and two years of soybeans without Telone II. Cotton following two years of soybeans was the only rotation to reduce final populations (P≤ 0.10) with Telone II. While no rotation produced significantly (P≤ 0.10) higher yields with or without Telone II, all rotations with the exception of one year of soybean produced numerically higher yields. Cotton following one year of corn, peanuts or soybeans without Telone II yielded 16%, 26%, and 17% higher than continuous cotton. One year of corn or peanuts with Telone II yielded 2% and 4% higher than continuous cotton.  Cotton following two years of corn, peanuts or soybeans yielded higher than continuous cotton by 34%, 46%, and 40% without Telone II, and 14%, 19%, and 13% with Telone II, respectively. All rotations resulted in an economic gain compared to continuous cotton with the exception of one year of corn with Telone II, and one year of soybean with Telone II. Cotton following two years of peanuts produced the largest economic increase compared to continuous cotton both with and without Telone II. The use of the correct crop rotation for the suppression of the reniform nematode can have a positive impact on cotton yields, even without the use of a nematicide.