Studies on fruit set and fruit drop in sweet lime (Citrus limettioides TANAKA)

The investigations on fruit set and fruit drop in sweet lime (Citrus limettioides TANAKA) were carried out under Delhi conditions (North India) during the year 1962-64, at the Indian Agricultural Research Institute. The effect of GA, 4-CPA, 2, 4-D and 2, 4, 5-T at different concentrations on fruit set, fruit drop and quality of sweet lime was studied. Gibberellic acid (750 and 1, 000ppm) gave the maximum fruit set followed by 2, 4, 5-T (20ppm), GA (500 ppm) and 2, 4, 5-T (7.5 and 10ppm).Plant growth regulator treatments proved ineffective against June drop. However, 2, 4-D (7.5 and 20ppm) and 2, 4, 5-T (7.5, 10 and 20ppm) proved most effective against pre-harvest drop.