FRUIT DROPS IN MANGO: A REVIEW

Abstract

Mango (Mangifera indica L.), the sixth most important fruit crop worldwide, Mango produces an abundance of
male and polygamous flowers, but only a small proportion of the latter group is successfully pollinated and has
the potential for setting fruit. Numerous abiotic and biotic factors reduce pollen viability, the fertilization
process of the flower, and embryo survival, which are all commonly associated with extensive fruit drop in early
season. 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 coincide 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. The number of
pollinators/panicle/minute increased as the average temperature increased to 19.5°C but decreased with further
increase in temperature and with rains. Isolates of Trichoderma spp. (ACB-14, ACB-33, ACB-37, and ACB-40)
and Bacillus subtilis (ACB-66, ACB-69, ACB-77, and ACB-83) were tested separately or in mixtures for
suppression of postbloom fruit drop in citrus, caused by Colletotrichum acutatum