Abstract :
The field experiments were conducted during 2010-11, 2011-12 and 2012-13 in Rabi season (Sep - Feb) at Agricultural
Research station, Kovilpatti to study the response of Bt cotton to different dates of sowing under varying spacing. Experiments were laid out in split-plot design with three replications. The treatment combinations comprised of three dates of sowing, viz., 39th, 41st and 43rd standard weeks (pre-monsoon, monsoon and post-monsoon sowing, respectively) in main plot with four different spacing of 90 x 60, 90 x 45, 75 x 60, 75 x 45 in the sub plot. The results of the experiment revealed that, pre-monsoon sowing of cotton (NCS 145) registered increased growth and yield parameters viz., plant height, DMP, LAI, number of bolls/plant, boll weight, which reflected on increased yield of cotton kapas (1434, 2430 and 347 kg ha-1) in 2011, 2012 and 2013, respectively. Similarly among the spacing tried, 75 x 45 cm (S4) registered increased plant height, dry matter production, LAI and number of symbodial branches which reflected on increased kapas yield which was followed by spacing of 90 x 45 cm. Interaction result shows that, 39th standard week (pre-monsoon) sowing with narrow spacing of 75 x 45 cm registered increased kapas yield under rain-fed condition.
Keyword :
Cotton, Growth, Spacing, Sowing window, Yield