Preventive Regulation of Jelly Seed Disorder in ‘Amrapali’ Mango (Mangifera indica) by Preharvest Spray

Abstract

Jelly seed, a physiological disorder in ‘Amrapali’ mango fruit, is characterized by the excessive softening of pulp around the stone in ripe fruits. The disorder is caused by the onset of germination associated events in the seed of developing fruit due to decreased level of very-long-chain fatty acids (VLCFAs) in seed. Field trials involving preharvest application of spray formulations on developing fruits, between 50% and 60% maturity, showed that formulation V (10 g·L−1 NaCl, 25 g·L−1 CaCl2, 0.5 g·L−1 KCl, 0.01 g·L−1 H3BO3, 0.01 g·L−1 CuSO4, 0.01 g·L−1 ZnSO4, 0.01 g·L−1 FeSO4, 0.01 g·L−1 MnSO4, and 0.002 g·L−1 EDTA) was the most effective in preventing the jelly seed disorder. Further studies to understand the mode of action of the formulation in controlling jelly seed development, revealed increased synthesis of VLCFAs in seed followed by the rapid production of ABA and germination-inhibiting phenolic acids, besides increased accumulation of calcium in seed. These factors acting in unison delayed seed germination and decreased the activities of pectinolytic enzymes in pulp to produce healthy fruits, free from jelly seed disorder. There was an increase of mineral nutrient content in pulp of treated healthy fruits. Thus, the study helped to develop a remedy to prevent jelly seed besides revealing the biochemical mechanism by which formulation V acted to produce ‘Amrapali’ mango fruits free of jelly seed with improved nutritional quality.