Endogenous hormones and polyamines in relation to fruitlet retention in mango cv. Alphonso.
Murti G. S. R., Upreti K. K.
Author Affiliation: Plant Hormones Laboratory, Indian Institute of Horticultural Research, Hessaraghatta Lake Post, Bangalore 560 089, India.
Journal of Plant Biology 26 : 149-154
Abstract : Studies on endogenous hormones, IAA, cytokinins, abscisic acid (ABA) and polyamines in the intact and abscised fruitlets of mango cv. Alphonso at mustard and pea stages revealed that the levels of cytokinins, dihydrozeatin riboside (DHZR), t-zeatin riboside (t-ZR), IAA and polyamines were higher in the intact fruitlets, and ABA was higher in the abscised fruitlets both at mustard and pea stages. Between the two fruit growth stages, the content of IAA was higher at pea stage, and DHZR and ZR at mustard stage in the intact fruitlets while differences in ABA were not prominent. Putrescine was found in relative abundance in intact fruitlets followed by spermine at mustard stage. At pea stage, however, spermidine followed by putrescine was present in higher concentration in intact as well as abscised fruitlets. There was greater variation in polyamine levels between the two categories of fruitlets at mustard stage than at pea stage. The results indicate that the hormonal imbalance marked by reduction in growth promoters, IAA, DHZR and t-ZR and polyamines, coupled with increase in growth inhibitor ABA, coincides with high incidence of drop of mango fruitlets during early phase of development.