Effect of foliar application of chitosan on growth and yield in okra.

Abstract

Pot and field experiments were conducted in two consecutive years at the pot-yard and experimental field of Bangladesh Institute of Nuclear Agriculture, Mymensingh, during March to June 2010 and 2011, to investigate the effect of foliar application of chitosan, a growth promoter, on morphological, growth, biochemical, yield attributes and fruit yield of okra cv. BARIdherosh-1. The experiment comprised of five levels of chitosan concentrations viz ., 0 (control), 50, 75, 100 and 125 ppm. The chitosan was sprayed three times at 25, 40 and 55 days after sowing. The pot experiment was laid out in a completely randomized design and the field experiment in a randomized complete block design, both with four replicates. Results revealed that most of the morphological (plant height, leaf number plant -1 ), growth (total dry mass plant -1 , absolute growth rate, relative growth rate), biochemical parameters (nitrate reductase and photosynthesis) and yield attributes (number of fruits plant -1 and fruit size) were increased with increasing concentration of chitosan until 25 ppm, resulted the highest fruit yield in okra (27.9% yield increased over the control). However, the increment of plant parameters as well as fruit yield was not significant from 100 ppm of chitosan. Therefore, foliar application of chitosan at 100 or 125 ppm may be used at early growth stage to achieve a maximum fruit yield in okra.