Enhancing Fruiting, Yield, and Quality of Litchi with the Use of Gibberellic Acid and Zinc Sulphate

Abstract

An experiment was conducted during 2025 at the Horticulture Garden, Department of Fruit Science, College of Horticulture, Chandra Shekhar Azad University of Agriculture and Technology, Kanpur, Uttar Pradesh, to evaluate the effects of gibberellic acid (GA₃) and zinc sulphate (ZnSO₄), applied alone or in combination, on fruiting, yield and quality of 66-year-old litchi (Litchi chinensis Sonn.) cv. Rose Scented trees. Nine treatments were evaluated in a randomised block design with three replications, using one tree per treatment unit. A single foliar spray was applied after fruit set, and observations were recorded at 15-day intervals until harvest. The combined treatment GA₃ at 50 ppm + ZnSO₄ at 1.0% (T₉) produced the highest fruit counts at the pit-hardening (30.15) and ripening (24.59) stages, fruit length (4.56 cm), fruit diameter (4.59 cm), fruit weight (19.49 g), pulp weight (13.99 g), pulp: stone ratio (4.70), total sugar (14.83%), total soluble solids (22.97 °Brix), sugar: acid ratio (36.66) and fruit yield (53.06 kg/tree). It also recorded the lowest fruit cracking (1.68%), seed weight (2.98 g), rind weight (2.46 g) and titratable acidity (0.404%). T₈ (GA₃ at 50 ppm + ZnSO₄ at 0.5%) generally ranked next. These results indicate that a single post-fruit-set foliar application of GA₃ at 50 ppm with ZnSO₄ at 1.0% may improve fruit retention, quality and yield of cv. Rose Scented under the sub-tropical plains of Central Uttar Pradesh.