Effect of NAA (Napthaleneacetic acid) and 2, 4, 5-T (2, 4, 5-Trichlorophenoxyacetic acid) on fruit quality of apple cv. red delicious

Abstract

This explore was conducted to study the effect of NAA (Napthaleneacetic acid) and 2,4,5-T (2,4,5-Trichlorophenoxyacetic acid) on fruit quality of apple cv. Red Delicious. The highest soluble solid content (12.04˚B) and total sugars (9.70%) was found under T2 (Napthaleneacetic acid @ 20ppm) followed by T4 while as highest ascorbic acid content was recorded under T4 (5.58mg/100g). Fruit firmness of apple decreased significantly with the growth regulator treatments over control. Minimum fruit firmness 17.27 lb/inch2 was recorded in T2 (NAA @ 20ppm) followed by T1 (NAA @ 10ppm) and the maximum fruit firmness was recorded under control (17.59 lb/inch2). NAA and 2,4,5-T significantly differed with each other in lowering the starch content of fruits, however NAA @ 20ppm (6.78) being more effective than the 2,4,5-T @30ppm (6.75) in reducing the starch content of fruits. The TSS, total sugars was improved by growth regulators, while as malic acid percentage was lowered compared to untreated fruits. The sugars exhibited an increasing trend with the growth regulators. The effect of NAA on TSS and total sugars was observed more pronounced than 2,4,5-T. However, NAA promotes more ripening in apples, accelerated starch degradation, increased rot%, decreased fruit firmness and ultimately affected the fruit quality parameters.