Vol. 8, Issue 4 (2019)

Author(s):
M Uma Maheswari, S Murali Krishnasamy, M Kumar and N Sakthivel

Abstract:
Field experiments were carried out during winter irrigated seasons of 2017 and 2018 at Department of Cotton, Tamil Nadu Agricultural University, Coimbatore. The experiments were laid out in split plot design with three replications. Treatments comprised of three crop geometries viz., 75 cm x 10 cm (M₁), 75 cm x 20 cm (M₂) and 75 cm x 30 cm (M₃) and seven sub plots with foliar application of different doses of growth retardants along with one control viz., Cycocel 400 ppm (S₁), Cycocel 500 ppm (S₂), Mepiquat Chloride 100 ppm (S₃), Mepiquat Chloride 200 ppm (S₄), Maleic Hydrazide 400 ppm (S₅), Maleic Hydrazide 500 ppm (S₆) and Control (No Spray) (S₇). Crop was sown in raised bed with inclined plate planter and the major cultivation practices were carried out with machines. The machines used for cotton cultivation were, inclined plate planter for sowing, boom sprayer for pre emergence herbicide application, power weeder for weeding, drip irrigation system for irrigation and fertigation and harvesting was done manually. Cotton cultivated under 75 cm x 10 cm spacing in conjunction with foliar application of mepiquat chloride 200 ppm at 45 and 60 Days After Sowing (DAS) significantly influenced the root parameters like root length, root volume, root dry weight and yield attributes like number of sympodia, number of bolls per plant, boll weight and seed cotton yield.