Effects of gibberellins on growth of cotton (Gossypium hirsutum L. cv. 'IAC-RM3')

Abstract

Seedlings of cotton were treated 19 days after the sowing with gibberellins at concentrations of 2, 20 and 200 ppm and the check to verify The effect of the compound on the growth of the plant. The experiment was done under greenhouse conditions in 1974. The main proposal of this work is to study the variation of plant height, net assimilation rate, relative growth rate and the leaf area ratio with application of gibberellins. The growth regulator at concentrations of 2, 20 and 200 ppm increased plant height, respectively in 27, 48 and 65% when compared to the control. Application of gibberellins at concentrations of 2 and 20 ppm promotes increase in the net assimilation rate and in the leaf area ratio of cotton. The relative growth rate was superior in the plots that received gibberelins at concentrations of 2, 20 and 200 ppm. It was verified that gibberellins at 200 ppm has a tendency to promote reduction in the net assimilation rate and slight variation in the leaf area ratio in relation to check.