Growth, yield and seed production of okra as influenced by different growth regulators

Plant growth regulators (PGRs) affect various aspects of plant physiology, mainly vegetative and reproductive traits including yield and seed production. Therefore, different concentrations (0, 50, 100 and 200 ppm) of gibberellic acid (GA3) and naphthalene acetic acid (NAA), alone or in different combinations were sprayed on okra plants at 2-true leaf stage, to ascertain their impact on plant growth, pod production, seed yield and seed quality. All variables regarding vegetative and reproductive growth were significantly influenced by different concentrations of the growth regulators except number of days taken to flowering. Growth regulators were less effective when applied individually as compared to their combined use; however, performance of plants treated with individual PGR was better than the untreated plants. The number of leaves plant/sup -1/ and plant height was higher in plants when sprayed with GA/sub 3/ and NAA at the rate 200+100 ppm as well as with GA/sub 3/ and NAA at the rate 200+200 ppm. The number of pods plant/sup -1/, pod length, pod fresh and dry weight, seed yield and seed quality (in terms of germination percentage and 1000-seed weight) was maximum in plants receiving foliar spray of both GA3 and NAA at the rate 200+200 ppm. These results signify the role of GA/sub 3/ and NAA in okra pod production for fresh consumption as well as for seed yield. (author)