effect of foliar application of naphthalene acetic acid and plant thinning on growth, yield and fruit quality of melon (cucumis melo cv. khatooni).

in order to study the effects of foliar application of naa and plant thinning on growth, yield and fruit quality of melon genotype khatooni, the experiment was conducted in a randomized complete block design with three replications at research field of faculty of agriculture, university of zanjan. treatments consisted of foliar application of naa at three levels (25, 50 and 100 mg.l-1 at 4-6 true leaf and fruit set stages), pruning (pruning against nonpruning) and plant thinning. treatment with naa increased the total soluble solids content of fruit. an obvious gradient of tss was detected, ascending from pedicel to umbilicus part of mesocarp. the maximum leaf area, fruit width and mesocarpe thickness was observed in naa (100 mg.l-1 at fruit set stage). naa caused a significant decrease in time to ripening. among the treatments, the highest number of fruits per plant and total yield was recorded by using naa (50 mg.l-1 at 4-6 leaf stage). also maximum mean fruit weight and marketable yield was obtained in plant thinning treatment. according to the results, foliar application of naa (100 mg.l-1 at fruit set stage) can be proposed instead of plant thinning practice that require too much time and labor for the farmers.