Evaluation Of Growth And Development In Mango Fruits Cvs. Julie And Peter To Determine Maturity
Two mango cultivars viz., Julie and Peter, were studied for growth and development of fruits in 2001 and 2002 starting from 47 days after fruit set (DAFS) till ripening. The objective was to determine the optimum stage of fruit maturity and consequently the proper time to harvest the fruits in order to minimize post-harvest losses. The mango fruits were assessed through various physico-chemical parameters at 9 – 10 day intervals at initial stages (47 – 93 DAFS) and at 7-day intervals at later stages (103-117 DAFS) of growth. Seven dates of harvesting after fruit set in Julie and nine harvesting dates in Peter mango constituted the treatments. For each date of harvest, 12 mango fruits were manually and randomly plucked from the trees and handled intact. The fruits were then divided into 4 equal groups with 3 fruits in a group as a replication. Data on maturity indices recorded for two years were pooled and subjected to analysis of variance procedures for randomized complete block design. Results showed that fruit development took longer duration in Peter mango (117 DAFS) compared to Julie mango (100DAFS) and Peter was classed a late mango cultivar. Development of an integument at the proximal end of the mango fruit was completed at 88 DAFS in Julie and at 100 DAFS in Peter, which indicated physiological maturity stage of the mango fruits. Specific gravity value greater than 1.0 was noted at 93 DAFS in Julie and 103 DAFS in Peter mango. At the same time, the endocarp completed its development. Although physiological maturity occurred earlier, the completion of endocarp development indicated that mango fruits have reached harvest maturity later at 93 DAFS in Julie and 103 DAFS in Peter. There was leap increase in TSS/acid ratio, upsurge in β-carotene content and change in pulp colour from whitish yellow to deep yellow which started from 93 DAFS in Julie and 103 DAFS in Peter. These observations suggested that mango fruits have attained harvest maturity. Therefore, mango fruits can be harvested at maturity between 93-100 DAFS in Julie and 103-117 DAFS in Peter. Post-harvest shelf life of mango fruits was more in Peter (8-10 days) than in Julie (4-7 days).
Key Words: Growth, Development, Harvest maturity, Mango fruits, Physicochemical parameters.
Bio-Research Vol.2(2) 2004: 22-26