Effect of Planting Date and Seeding Rate on Growth and Development of Cotton in the Texas High Plains

Increasing seed cost is one of the biggest challenges facing cotton producers in the Texas High Plains, particularly those associated with the popular new herbicide traits.  Environmental conditions, particularly in the spring lead to delayed planting or replant scenarios being commonplace.  To determine how growth and development of cotton is impacted by the amount of seeds planted per acre and the timing of planting, three different seeding rates that are commonly utilized by producers in the region (25k, 35k, and 45k seed per acre) were planted at three different planting dates, early May (May 8^th), late May (May 31^st), and mid-June (June 9^th).  Two cultivars, Deltapine 1646 B2XF and NexGen 3406 B2XF were utilized.  Both cultivars are popular among cotton producers in the High Plains, and represent early-mid (3406) and late (1646) maturing cultivars.  While seeding rate can be used to mitigate input costs, one objective of this study was to determine the impacts of these varying seeding rates on growth (plant height) and reproductive development (nodes above white flower) of cotton,  and how planting date influenced these parameters.  An additional objective, and one characteristic that is of particular importance for cotton in the Texas High Plains is earliness, so various end of season parameters (total nodes, node of first fruiting branch, node of uppermost cracked boll, and node of uppermost harvestable boll) were quantified to determine which of the various seeding rates and planting dates hastened or delayed maturity.