Cotton Water Use and Lint Yield in Four Great Plains Soils

The development of earlier maturing, cool temperature tolerant varieties of cotton (Gossypium hirsutum L.) has allowed cotton production to expand into regions with shorter, cooler growing seasons. The objective of this research was to evaluate the interactive effect of soil type, irrigation, and meteorological conditions on the water use and lint yield of cotton grown in four U.S. Great Plains soils. Cotton was grown in 2005 through 2007 in 48 weighing lysimeters which contained clay loam, silt loam, sandy loam, or fine sand at Bushland, TX, with irrigation beginning after emergence. The seasonal heat units (HU) from planting to harvest were 1010°C in 2005, 1075°C in 2006, and 985°C in 2007. From seedling to beginning boll development, reference evapotranspiration averaged 7.6 mm in 2005, 8.5 mm in 2006, and 6.7 mm in 2007. Lint yield was significantly related to open boll number at harvest in all soils and years. Averaged cotton lint yields for the 2005 and 2007 full and deficit irrigation treatments were significantly larger in the fine sand (160 g m−2) than in the other soils (126 g m−2). In 2006, cotton lint yield in the fine sand was significantly smaller (101 g m−2) than the average of the other soils (147 g m−2). Cotton lint yield increased in the silt loam soil and decreased in the fine sand as seasonal HU increased. Early season meteorological conditions which influenced square shedding and boll development may have affected lint yields interactively with soil texture and irrigation.