International journal of research in agronomy growth, yield and economics in high density planting system and canopy management practices in Bt cotton under drip irrigation

Abstract

A field trial was conducted at Cotton Research Farm, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola during the kharif season of 2024-25 to evaluated the Growth, yield and economics in high density planting system and canopy management practices in Bt cotton under drip irrigation. The experiment was laid out Factorial Randomized Block Design with three replications and twelve treatment combinations. The field was equipped with an inline drip irrigation system with 16 mm laterals placed at 90 cm apart and drippers spaced 40 cm apart. The results showed that planting at 90 cm x 45 cm provided better crop growth, dry matter accumulation, leaf area, chlorophyll content, number of sympodial branches per plant, number of picked bolls per plant, and seed cotton yield per plant compared to plant spacing of 90 cm x 15 cm and 90 cm x 30 cm. However, the plant spacing of 90 cm x 15 cm gave the highest seed cotton yield at 4121 kg/ha and highest harvest index of 45.78, which was significantly better than the wider spacing. This also led to the highest gross monetary return (300761 Rs/ha), net monetary return (202209 Rs/ha) and a better benefit:cost ratio (3.05) compared to wider spacing. The study also found that canopy management practices, such as monopodia removal at 45-50 DAS and detopping at 100 cm plant height, helped to increase the number of sympodial branches per plant, number of picked bolls, seed cotton yield per plant, and overall seed cotton yield in kg/ha as compared to no canopy management. The treatment involving monopodia removal at 45-50 DAS and detopping at 100 cm plant height gave the highest seed cotton yield of 4119 kg/ha, along with the highest GMR (300484 Rs/ha), NMR (202050 Rs/ha), and B:C ratio (3.05) compared to the control. The second best treatment of seed cotton yield (3859 kg/ha) was recorded in the C4 treatment (two sprays of mepiquat chloride @25 g a.i. at 45-50 DAS and 60-65 DAS)