Effect of nutrient management practices on growth, yield attributes and yield of coloured cotton (Gossypium hirsutum L.)

The field experiment was carried out at the Central Farm, AC &RI (Agricultural College and Research Institute), TNAU, Madurai, Tamil Nadu during Kharif season 2024. The study aimed to evaluate the effects of different nutrient management strategies on the growth, yield components and productivity of coloured cotton. The experiment followed a randomized block design (RBD) with nine treatments based on nitrogen equivalence, incorporating different organic manures in comparison to inorganic fertilizers, with each treatment replicated three times. The results revealed that growth parameters such as plant height, dry matter production, leaf area index, chlorophyll content, number of monopodial branches plant-1 , days to 50% flowering and days to 50% boll bursting were significantly enhanced by the application of 100% NPK based on site-specific recommendation (T2), which statistically at par with 100% NPK through blanket recommendation (T1). Yield attributes including number of fruiting branches plant-1 , number of fruiting points plant-1 , number of bolls plant-1 , number of bolls m-2 , boll setting percentage and boll weight, along with seed cotton yield, lint cotton yield, stalk yield and biological yield, which also showed a significant increase with the application of 100% NPK through site-specific recommendation (T2). Organic treatments, including the complete organic package (T9), cover cropping with 75% N through vermicompost (T4) and cover cropping with 75% N through poultry manure (T5), exhibited comparable results to inorganic treatments. Future research should focus on optimizing organic nutrient management strategies and integrating cover crops to enhance soil health and ensure sustainable cotton production.