Yield Potential, Fiber Quality and Adaptability of Glandless Cotton In New Mexico

The prospect of commercial cultivation of glandless cotton (cotton plants without gossypol) will widen the utility of cottonseed beyond the present main use as ruminant animal feed, and this could result in higher income for cotton growers in New Mexico. Previous evaluations of glandless cotton in New Mexico have been unsuccessful due to pressures from insect and vertebrate pests, and poorly adapted cultivars. However, the State of New Mexico is now characterized as a low pest pressure zone for cotton production, with the near eradication of pink bollworm and boll weevil pests. Thus, the environment of New Mexico may now be more favorable to grow glandless cultivars of cotton. An upland cultivar of glandless cotton (Acala-GLS) bred for California conditions was evaluated in New Mexico and compared to conventional glanded Acala cultivars (Acala 1517-08 and Acala 1517-99). A total of four sites (two on-station and two commercial farms) were selected for this study. The cotton cultivars were planted on beds spaced 40 inches apart and irrigated by furrows and/or sprinklers. After maturity, yield was evaluated in 2-rows that are 20ft long in each plot. Results showed that the Acala-GLS cultivar generally had lower yields when compared to the conventional glanded Acala cultivars of New Mexico. Yield was also variable with sites and management practices. Some damages on the leaves due to beet armyworm feeding were observed in the glandless cotton at one of the sites, but this does not appear to have significant impact on boll formation. Generally, the conventional cultivars showed more vigor compared to the glandless cultivar. Average boll number per acre was 40% higher and the plant height was 20% higher in the conventional cultivars compared to the glandless cultivar. Conventional glanded cultivars gave 18-36% higher yield than the Acala-GLS cultivar.