Development of Longterm Stewardship Practices in XtendFlex Cotton and Economic Analysis for Grower Adoption in Texas

Abstract

Field trials were conducted during 2019-2021 at two locations in Texas to evaluate the efficacy and profitability of dicamba based herbicide programs under continuous cotton production and cotton: sorghum: cotton rotation for three years in no-till cover cropping, strip tillage and conventional tillage. Seasonal weed control data for Palmer amaranth at irrigated and dryland environments, barnyard grass control at irrigated environments, Texas panicum control at dryland environment, cotton and sorghum yields, as well as fiber quality data were collected during 2019-2022. Similarly, cover crop biomass and, Palmer amaranth density at different timings during the growing season were collected during 2020-2021. Cumulative distribution function analysis and stop light chart analysis were conducted using the variability of net returns for each treatment and ranked their economic success. Conventional tillage showed significantly lower in-season Palmer amaranth densities and seedbank compared to no-till cover cropping and strip tillage at both locations. Using high input herbicide program (HI) under cotton: sorghum: cotton rotation provided >90% Palmer amaranth, barnyard grass, and Texas panicum control in College Station and Thrall during the three years. Conventional tillage produced significantly higher seed cotton yields compared to no-till cover cropping in Thrall, whereas no consistent effect of single tillage practice was observed on seed cotton and grain sorghum yields in College Station. No significant difference for seed cotton and grain sorghum yields were observed between herbicide programs at either location. Cumulative density function analysis and stop light charts confirm that using low input herbicide programs under cotton: sorghum: cotton rotation provides significantly greater net returns compared to other treatments in all tillage types at Thrall.