Influence of Varied Plant Densities and Nitrogen Doses on Growth and Yield of Bt cotton (Gossypium hirsutum L.) Under High Density Planting System

A field experiment was conducted at College farm, College of Agriculture, PJTSAU, Hyderabad during kharif, 2021-22 to study the growth and yield of Bt cotton as influenced by varied plant densities and nitrogen doses under high density planting system. The results revealed that among plant densities, plant height (102.8 cm) and drymatter production (7396 kg ha-1) were higher with spacing of 90 x 15 cm (74,074 plants ha-1) and was on par with spacing of 90 x 20 cm (55,555 plants ha-1). Whereas, sympodial branches plant-1 (21.0) and leaf area (4143 cm2 plant-1) were recorded higher with spacing of 90 x 60 cm (18,518 plants ha-1). Even though at spacing 90 x 60 cm (18,518 plants ha-1) showed more number of picked bolls plant-1 (18.2), boll weight (5.10 g) but 90 x 15 cm spacing (74,074 plants ha-1) showed significantly higher seed cotton yield (2176 kg ha-1) which was at par with 90 x 20 cm (55,555 plants ha-1) (2052 kg ha-1). In case of nitrogen doses, application of 180 kg N ha-1 recorded higher growth parameters like plant height (103.2 cm), sympodial branches plant-1 (20.8), drymatter production (6952 kg ha-1) and leaf area (3826 cm2 plant-1). Whereas, application of 150 kg N ha-1 recorded higher seed cotton yield (2072 kg ha-1) with more number of picked bolls plant-1 (12.9) and higher boll weight (4.87 g) over other nitrogen doses tested.