Effect of irrigation regimes on insect populations in Texas High Plains cotton

Abstract

Influence of irrigation application rates and irrigation application methods on cotton insect populations were studied in Texas High Plains during 2002. Cotton pests, including Lygus bugs and cotton fleahoppers, and beneficial arthropods were sam- pled. Three irrigation application rates, 50%, 75% and 100% evapotranspiration (ET) replacements, were evaluated. The two irrigation application methods evaluated were low energy precision application (LEPA) system and low elevation spray ap- plication (LESA) system. Four commercial cotton cultivars, ST2454R, PM2326RR, ST4793R and DP5415RR were evalu- ated. Insect populations were sampled using a vacuum sampler. Insect numbers were higher in LEPA irrigated plots than in LESA irrigated plots. Overall, insect numbers were higher at 75% ET replacement followed by 100% and 50%, respectively. The cultivar PM2326RR had the highest Lygus and fleahopper numbers and lowest predators compared with the other three cultivars.