Fruit and leaf drop at early stages can be prevented by the...

Among the various types of growth promoters in plants, Auxins, Gibberellins and Cytokinins are most common and well characterized. The Auxin delay abscission of leaves and fruits at early stages. Whenever leaf or fruit fall occurs, the organ concerned stops producing auxin. However, it promotes abscission of order, mature leaves, and fruit. Abscision is a natural phenomenon of old parts. Primarily this is accomplished by Abscisic acid hormone (ABA). NAA prevents fruit drop in tomato; 2,4-D prevents fruit drop in Citrus.

Cytokinins are mainly involved in cell division. Gibberellins are mainly involved in stem internode elongation.