Naturally occurring auxins and inhibitor and their role in fruit growth and drop of mango ‘Dashehari’

Abstract

The pattern of fruit growth in mango ‘Dashehari’ ( Mangifera indica L.) was sigmoid. Pollinated ovaries and young fruits dropped in two main waves: 0–14 days and 28–35 days. A third wave, a mild one, was continuous and irregular from 35 days after pollination to maturity of the fruit. One acidic and one non-acidic auxin and one acidic inhibitor were detected in the immature fruit. The increase in the levels of auxin corresponded with a period of rapid fruit growth, while high levels of inhibitor tended to correspond with a high rate of fruit drop from pollination to 42 days. The auxins appear to play a major role in the growth of the fruit, whereas the inhibitor appears to cause fruit drop.