PLANT CELL BIOTECHNOLOGY AND MOLECULAR BIOLOGY

A field experiment was conducted during 2025-26 at the Nursery Farm, Department of Fruit Science, C.S. Azad University of Agriculture and Technology, Kanpur (U.P.), to evaluate the response of aonla (Emblica officinalis L.) cv. NA-7 to foliar sprays of gibberellic acid (GA₃) and naphthalene acetic acid (NAA), applied singly and in combination. Nine treatments comprising GA₃ at 25 and 50 ppm, NAA at 25 and 50 ppm, their four combinations, and a water-sprayed control were evaluated in a Randomised Block Design with three replications; sprays were applied at flowering and post-fruit-set stages. All recorded parameters responded significantly to the treatments. The combined spray of GA₃ 50 ppm + NAA 50 ppm (T₈) consistently produced the best response among the treatments: fruit drop decreased to 19.10% compared with 62.10% in the control, fruit retention increased to 80.90%, and yield reached 216.00 kg per plant, representing a 32.52% increase over the untreated trees. The same treatment produced the longest, widest, and heaviest fruits, the highest pulp weight, and the most favourable pulp-to-stone ratio (21.09, approximately 1.78 times that of the control). In terms of quality, it increased total soluble solids to 12.20°Brix, reduced titratable acidity to 1.72%, increased the TSS:acid ratio to 7.09, and increased ascorbic acid content to 608.32 mg per 100 g pulp. These results suggest a synergistic response to the combined application of GA₃ and NAA rather than a simple additive effect and support the use of GA₃ 50 ppm + NAA 50 ppm to reduce pre-harvest fruit drop and improve yield and fruit quality in aonla cv. NA-7 under the agro-climatic conditions of the Central Plain Zone of Uttar Pradesh.