Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Abstract Only
Publication Acceptance Date: 3/1/2014
Publication Date: 3/1/2014
Citation: Allen, K.C., Adams, D.A., Luttrell, R.G., Little, N. 2014. Recent evaluations of Bt and non-Bt cotton in the Mississippi Delta. National Cotton Council Beltwide Cotton Conference. Proceedings of the Beltwide Cotton Conferences, January 6-8, 2014, New Orleans, LA. p.886.
Technical Abstract: Since the introduction of the first transgenic cotton for the control of caterpillar pests in 1996, there has been interest in evaluating the cost of control and the resulting yields of these transgenic traits in both sprayed and unsprayed environments. During the 2011 growing season, five locations were established in areas of the Mississippi Delta to examine the returns above of using two different insecticides (chlorantraniliprole and lamba cyhalothrin) on transgenic cotton varieties possessing two genes for caterpillar control (Bollgard II® and Widestrike®) and non-Bt cotton. During 2012 and 2013, an additional nine and eight locations, respectively, were evaluated including both shorter and longer season cotton varieties. Plots were treated when bollworm/tobacco budworm (heliothine) populations reached densities recommended for control according to the Mississippi Insect Control Guide with the highest recommended rate of insecticide. Overall, larval populations were greater in 2011 compared with 2012 and 2103. Returns of non-Bt plots were greater when treated with either insecticide in locations where threshold populations of heliothines were encountered. The comparative returns of Bollgard II® and Widestrike® plots varied with the insecticide used and location of the plots.