Glandless Cotton in New Mexico: Weighing the Risk of Insect Losses

Glandless cotton has been rejected as a viable crop in some areas since the lack of gossypol resulted in a plant that was highly susceptible to losses from insects.  New Mexico has lower insect pressure than most other areas of the cotton belt and might be an area where gossypol cotton is a viable roduct.  Field trials with a gossypol free Acala cotton were initiated in 2010 in New Mexico.  In 2011, trials were initiated on a University farm to evaluate insect losses in the field and lab.  Laboratory trials were conducted to evaluate preference and survival of cotton bollworm and beet armyworm on the glandless Acala GLS and the local standard Acala 1517-99.   Initial results indicate some differences in preference and significantly higher weights for 4^th instar larvae fed the glandless Acala.

Possible differences in predation were also evaluated by direct sampling of predators in glanded and glandless cotton.  Predation levels were also compared by placing sentinel eggs in the field then examining the retrieved eggs under a microscope for signs of predation.