|Stetina, Salliana - Sally|
Submitted to: Plant Health Progress
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/12/2009
Publication Date: 3/12/2009
Citation: Stetina, S.R., Sciumbato, G.L., Young, L.D., Blessitt, J.A. 2009. Cotton Cultivars Evaluated for Tolerance to Reniform Nematode. Plant Health Progress. doi:10.1094/PHP-2009-0312-01-RS Interpretive Summary: The reniform nematode has become the most damaging nematode on cotton in the Mid South area of the United States. Though tolerant cultivars support growth and reproduction of the nematode, they do so without associated reductions in yield of the cotton plant and therefore may be beneficial to growers from an economic perspective. Field trials conducted in west-central Mississippi identified only three cultivars of the 39 tested that did not appear to suffer significant yield loss in the presence of reniform nematode: Suregrow 215 BR, Paymaster 1218 BR, and Deltapine 449 BR. Unfortunately, based on our results and other recent reports, it appears that tolerant cotton cultivars are not widely available. It is important for growers to choose cultivars adapted to their region and their farm, keeping in mind that the few with tolerance may not be the best fit for any one farming operation.
Technical Abstract: Thirty-nine commercial cotton (Gossypium hirsutum) cultivars were evaluated to identify those with tolerance to reniform nematode (Rotylenchulus reniformis). Trials were conducted for three years at two west-central Mississippi field locations naturally infested with reniform nematode. Main plots were cultivars and subplots were either not treated or treated with nematicide. Reniform nematode soil population densities were assessed throughout the growing season. At harvest, seed cotton yields were determined, and fiber quality was evaluated for select samples. Data were pooled from all years and locations, and t-tests were used to identify tolerant cultivars. Cultivars were judged tolerant if nematicide did not improve yield, although the nematode population was reduced at a midseason sampling interval. Only Deltapine 449 BR, Paymaster 1218 BR, and Suregrow 215 BR met these criteria. Additionally, tolerance indices were calculated for nine cultivars showing suppressed nematode populations in nematicide-treated plots at any point during the growing season. The three tolerant cultivars identified based on the t-tests ranked first (Suregrow 215 BR), second (Paymaster 1218 BR), and fifth (Deltapine 449 BR) with respect to tolerance index. Because they do not appear to suffer significant yield loss due to reniform nematode, these three cultivars may benefit growers.