Performance Evaluation and Stress Screening of Colored Cotton Genotypes for Yield, Fiber Quality and Drought Tolerance

Abstract

Naturally colored cotton (Gossypium hirsutum L.) offers an eco-friendly alternative to conventional white cotton by reducing the need for synthetic dyes. However, its cultivation remains limited due to lower yield and suboptimal fiber quality, particularly under drought stress. We evaluated the genetic and physiological performance of 20 white and naturally colored cotton genotypes under normal and water-deficit conditions using field trials (RCBD) and laboratory PEG (polyethylene glycol)-6000 screening (CRD). Agronomic, fiber quality and physiological traits were recorded, including plant height, bolls per plant, seed cotton yield, lint weight, fiber length and strength, chlorophyll content, photosynthetic rate and stomatal conductance. Significant genotypic variability was observed for most traits. Drought reduced yield and fiber strength most markedly in green-colored genotypes, whereas Light Brown and Khaki American A maintained higher photosynthetic rates, chlorophyll content and yield stability under limited irrigation. Path coefficient analysis identified lint weight, boll weight and fiber length as key contributors to seed cotton yield. These findings demonstrate that integrating genetic selection with physiological screening (field + PEG assays) can accelerate breeding of drought-resilient colored cotton, offering practical value to breeders and the textile industry in water-limited regions.