Influence of Plant Growth Regulators in Enhancing Fruit Retention, Yield, and Quality of Anola (Emblica officinalis L.)

Abstract

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.