EFFECT OF PRE-HARVEST APPLICATION OF GA3 AND POTASSIUM NITRATE ON YIELD AND QUALITY OF PEACH FRUIT

Abstract

The research study entitled “effect of pre harvest application of GA3 and potassium nitrate on yield and quality of peach fruit” was carried out at Horticulture Research Farm, The University of Agriculture Peshawar during 2019. The plots were arranged using Randomized Complete Block Design (RCBD) with two factors. Three replications were used in the experiment. The experiment was conducted on already established peach orchard of almost 14 years old trees of Early Grande cultivar. The uniform size trees were selected and tagged for the experiment. The plants were managed under uniform cultural practices. The selected plants of peach cv. Early Grande were sprayed with various concentrations of Gibberellic acid (GA3) (0, 20, 40, 60 and 80 ppm) and potassium nitrate (KNO3) (0, 1000, 2000 and 3000 ppm) at berry stage. Peach plants were sprayed with GA3 and KNO3 and compared with control. The analysis of data showed that the foliar application of GA3 and KNO3 significantly influenced the yield and quality attributes of peach. Maximum fruit weight (111.98 g), chlorophyll content (51.00 SPAD), TSS (14.60 oBrix), fruit juice content (85.80 %), Fruit firmness (2.16 kg.cm-2), yield plant-1 (54.56 kg) and yield ha-1 (15.548 tons) were recorded in plants treated with 80 ppm of GA3. In case of KNO3 Maximum fruit weight (101.20 g), chlorophyll content (49.46 SPAD), TSS (13.38 oBrix), fruit juice content (84.86 %), Fruit firmness (2.12 kg.cm-2), yield plant-1 (51.56 kg) and yield ha-1 (14.829 tons) were recorded in plants treated with 3000 ppm of KNO3. Minimum days to maturity (72.52) and minimum number of fruits kg-1 (9.65) were found in plants sprayed with 80 ppm of GA3 while in case of KNO3 minimum days to maturity (76.92) and minimum number of fruits kg-1 (10.62) were found in plants sprayed with 3000 ppm of KNO3. Interactive effect of levels of GA3 and KNO3 was also found significant for some of the parameters. It is therefore concluded that when peach Early Grande cultivar sprayed with 80 ppm of GA3 and 3000 ppm of KNO3 the quality as well as yield of the crop were improved.