Increasing productivity of hybrid cotton by foliar spray of defoliators under various sowing methods and crop geometries

An experiment was conducted at Agricultural Research Station, Borwat Farm, Banswara during kharif -2011 and 2012 to find out the suitable sowing method, optimum plant geometry and defoliator for hybrid cotton under three sowing method (normal sowing, transplanting and crowbar method), three plant geometries (90 x 45, 90 x 30 and 60 x 30 cm) and three defoliators (i.e. ABA, cycocel and ethrel 1000 ppm). Significantly higher seed cotton yield was recorded (2151 kg ha⁻¹) under crow bar method as compared to transplanting and normal sowing methods. The maximum seed cotton yield was recorded with sowing of normal plant geometry of 90 x 45 cm (2059 kg ha⁻¹) over closer plant geometry of 60 x 30 cm, but it was found at par with 90 x 30 cm plant geometry. Though, yield attributing parameters such as bolls plan⁻¹ and boll weight were statically improved in normal as compared to closer plant geometry. Foliar spray of ethrel (1000 ppm) defoliator after boll development stage gave maximum seed cotton yield (2029 kg ha⁻¹) over cycocel (1000 ppm) and ABA (1000 ppm). Foliage part of the cotton plant dropped after defoliator spray, which is ultimately help in increasing boll weight and early boll opening.