HORMONAL CONTROL OF FRUIT GROWTH AND FRUIT DROP IN MANGO CV DASHEHARI

The pattern of fruit growth in mango cv Dashehari was sigmoid.
Investigations into the changes of hormonal concentrations revealed that auxin levels increased and decreased with the rate of fruit growth.
The gibberellin content in seed increased rapidly during early seed growth and declined as growth decreased.
The seed was the major source of gibberellin in the fruit, the pericarp containing only traces.
Cytokinins were present both in pericarp and seed.
During the single period of rapid growth in fruit and seed, cytokinin concentrations increased rapidly at two periods.
The first rapid increase in cytokinin concentrations preceds the period of rapid cell division and cell enlargement and the second increase coincides with the period of rapid cell enlargement only.
The level of ABA-like inhibitor was high in the first 21 d preceding pollination which corresponded with the period of slow growth in fruit and heavy fruit drop.
During the rapid period of fruit growth, the level of inhibitors decreased and that of promoters increased.
However, in maturation and slow fruit growth period, the levels of both the growth promoters and inhibitors were low.
Thus all the growth promoters play their role in the growth of the fruit.
Deficiency of auxins, gibberellins and cytokinins coupled with high level of inhibitors appear to cause fruit drop in mango cv Dashehari.

Regulation of Growth and Endogenous Hormones, XXI IHC

S. Ram

https://doi.org/10.17660/ActaHortic.1983.134.23