Effect of cotton population density on lint yield and fiber quality

Abstract

Commercial cultivars with advanced technology have reduced pest pressures, while greater seed costs have increased total production cost. Limited information is available on the optimal final population density (PD) for the commercially available cotton (Gossypium hirsutum L.) cultivars with advanced technologies in water-scarce environments. Therefore, our objectives were to examine the effects of PD on cotton growth and development, lint yield, fiber quality, and net return. A 2-year study was conducted to test four PDs (low, medium, high, and very high) in deficit-irrigated and dryland conditions at Chillicothe, TX. Final PD at 12 days after planting were 54,078, 109,563, 124,037, and 151,377 plant ha⁻¹ in irrigated and 67,346, 115,335, 116,397, and 145,432 plant ha⁻¹ in dryland trials. Maturity was delayed in the low PD early in the season; however, the differences on maturity ceased toward the end of the season. No statistical differences were observed on lint yield and fiber quality among treatments in irrigated and dryland trials. Average lint yields were 1199 kg ha⁻¹ in irrigated and 796 kg ha⁻¹ in dryland trial. Net returns were similar among all PD in the irrigated trial, while low PD had significantly higher net-return than very high PD in the dryland trial. The higher net return at the low PD was due to the lower seed cost associated with a low seeding rate. In the water-scarce environment, final plant density of 54,078 plant ha⁻¹ in deficit irrigation and 67,346 plant ha⁻¹ in dryland produced optimal yield and net return as compared to higher PD examined.