2024, Vol. 7, Special Issue 9

author(s)
Sai Durga C, Babu S, Karthikeyan A and Dhanasekaran K

abstract
The field experiment was conducted at field no.1 of G block of the Experimental Farm, Department of Agronomy, Faculty of Agriculture, Annamalai University, Annamalai Nagar, Cuddalore district of Tamil Nadu during the summer season (January to June, 2024) to evaluate the impact of plant growth regulators on cotton plant architect (Gossypium hirsutum L.). The experiment was laid out in a randomized block design with three replications. The experiment comprised of seven treatments of PGR application at 60 and 80 DAS and few at 50 and 70 DAS based on the plant monitoring approach viz., T₁ - Plant monitoring approach application of cyclanilide 2.10% + mepiquat chloride 8.40% w/w SC @ 0.6 ml L^-1 of water, T₂ - Plant monitoring approach application of cyclanilide 2.10% + mepiquat chloride 8.40% w/w SC@ 0.9 ml L^-1 of water, T₃ - Plant monitoring approach application of cyclanilide 2.10% + mepiquat chloride 8.40% w/w SC@ 1.2 ml L^-1 of water, T₄ - Application of cyclanilide 2.10% + mepiquat chloride 8.40% w/w SC@ 0.6 ml L^-1 of water at 60 and 80 DAS, T₅ - Application of mepiquat chloride 8.40% w/w SC@ 0.6 ml L^-1 of water at 60 and 80 DAS, T₆ - Nipping at 80 DAS, T₇ - Untreated check. The entire treatment was replicated three times. In the treatments including plant monitoring approach the chemical is sprayed at 50 and 70 DAS upon satisfying the criteria for the application. registered the beneficial results of growth characters, yield characters, yield and fibre quality characters of varietal cotton. Among the different PGR practices tested, application of the plant monitoring approach application of cyclanilide 2.10% + mepiquat chloride 8.40% w/w SC@ 1.2 ml L^-1 of water (T₃) significantly exerted a beneficial result in growth characters viz., plant height, plant dry matter production, number of main stem nodes, length between top fourth and fifth internodes, Height-to-node ratio with monopodial branches showing a non- significant effect, growth analysis viz., LAI and chlorophyll content in leaf.