Optimizing population managements for machine-harvested and drip-irrigated cotton

Abstract

Improving crop yield, quality and water use are crucial in dealing with climate change and water scarcity in arid regions. With the advent of wholly mechanized technology for cotton planting in Xinjiang, it is important to determine the mode with optimizing row configuration, plant density and topping. This study aims to explore the effects of two plant densities, chemical topping vs manual topping under two different common row configurations, i.e. 76 cm equal rows and 10+66 cm narrow-wide rows, which are used for matching harvest machine. The cotton growth, yield, fiber quality and transpiration,were investigated. Experiments were carried out in Xinjiang China, in 2020 and 2021. Seed yield was high in 10 plants m-2 for equal rows and 15 plants m-2for narrow-wide rows. Chemical topping increased fiber length by 2.1% comparing to the traditional manual. Micronaire was 9.6% higher in equal rows than in narrow-wide rows. Under equal row spacing, the WUE in 18 plants m-2 and was 62.4% higher than in 10 plants m-2. Under narrow-wide row spacing, the WUE in 15 plants m-2 was 53.3% higher than in 25 plants m-2. For machine-harvest cotton in Xinjiang, the optimal managements for both high yield and water saving could be 15 plants m-2, narrow-wide rows and applying chemical topping.The results provide a useful approach for optimizing cotton managements and water use.