Effect of Various Plant Growth Regulators on Growth and Yield of Cotton (Gossypium hirsutum)

Abstract

Plant growth regulators (PGR) are used in cotton (Gossypium hirsutum L.) production to balance vegetative and reproductive growth, as well as to increase seed cotton yield and lint quality. Field experiments were conducted with some PGRs to determine their effects on yield and yield components of cotton using cv Bt. Cotton and local hybrid. The field experiment was conducted during Kharif season of 2012-13 at the Agronomy Instructional Farm, Chimanbhai Patel College of Agriculture, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar, and District: Banaskantha (North Gujarat). The experiment was laid in factorial randomized block design with three replications. Eighteen treatment combinations comprised of the foliar spray of growth regulators and nutrients viz. 30 ppm NAA, 50 ppm GA3, 200 ppm Mepiquat chloride, 2 % Urea and control were applied at 60 and 80 days after sowing. The results showed that the applied PGRs had significant positive effects on plant height, leaf area index, higher number of flowers reduced the abscission and increased the flower retention percentage, which in turn helped in getting higher seed cotton yield. The RGR and NAR decreased continuously in all the treatments.