Sweet lime is one of the well-known citrus species, but due to its poor yield and quality farmers hesitate from its cultivation. Gibberellic acid is the key plant growth regulator which regulates various physiological activities in plants. In horticulture crops, Gibberellic acid is particularly applied to improve flowering, fruit set and fruit quality. Therefore in the present work the influence of Gibberellic acid concentrations (Control, 40, 50 and 60 ppm) and time of application (5, 10 and 15 days after bud break, DABB) on photosynthetic pigments, fruit quality and antioxidant enzymes of sweet lime was evaluated during the year 2020. Results of the current study demonstrated that Gibberellic acid at 50 ppm produced high values of Chlorophyll (Ch) a, Ch b, Ch a+b, carotenoid content, fruit juice content, vitamin C, superoxide dismutase (SOD) and peroxidase dismutase (POD) activity, while the highest fruit firmness and total soluble solids (TSS) were recorded with 40 ppm GA(3). Whereas, the application of GA(3) on 15 DABB significantly increased Chlorophyll a, Ch b, Ch a+b, carotenoid content, fruit juice content, vitamin C, POD and SOD activity. Maximum TSS, and total sugars were produced on 10 DABB application that was statistically at par with 15 DABB application. Hence it is recommended that GA(3) must be applied at 50 ppm on 15 DABB for enhanced photosynthetic pigments, fruit quality and antioxidant enzymes.
