Tuesday, December 12, 2006

Yield compensation from simulated bollworm (Helicoverpa zea) losses in Acala1517-99

Jane Breen Pierce, japierce@nmsu.edu1, Patricia Yates Monk, pyates@nmsu.edu1, and Patricia F. O'Leary, poleary@cottoninc.com2. (1) New Mexico State University, Entomology, Plant Pathology and Weed Science, 67 E. Four Dinkus Road, Artesia, NM, (2) Cotton Incorporated, 6399 Weston Parkway, Cary, NC

Field trials were conducted in the Mesilla and Pecos Valleys of New Mexico to determine if cotton can compensate for heavy mid to late season bollworm injury. Cotton compensated primarily by retaining more squares and bolls. Removal of 4 squares per plant resulted in 29-30 bolls/ft the same as control plots despite the removal of 10 squares/ft. Cotton also compensated or even overcompensated by producing more lint per lock in developing bolls. The highest yield 1620 lb/A was from plots with 4 squares removed per plant. Mean lint weight /lock was 12% higher in those plots compared to control plots. Boll removal was more difficult to compensate than square losses. Removal of 4 bolls per plant on 8/29 and 9/12 resulted in 10% and 30% less lint respectively. Removal of eight bolls over two weeks resulted in 49-57% yield losses.

Species 1: Lepidoptera Noctuidae Helicoverpa zea (cotton Bollworm)