May. 21, 2013
HarvestingMangos normally reach maturity in 4 to 5 months from flowering. Fruits of "smudged" trees ripen several months before those of untreated trees. Experts in the Philippines have demonstrated that 'Carabao' mangos sprayed with ethephon (200 ppm) 54 days after full bloom can be harvested 2 weeks later at recommended minimum maturity. The fruits will be larger and heavier even though harvested 2 weeks before untreated fruits. If sprayed at 68 days after full bloom and harvested 2 weeks after spraying, there will be an improvement in quality in regard to soluble solids and titratable acidity.
When the mango is full-grown and ready for picking, the stem will snap easily with a slight pull. If a strong pull is necessary, the fruit is still somewhat immature and should not be harvested. In the more or less red types of mangos, an additional indication of maturity is the development of a purplish-red blush at the base of the fruit. A long-poled picking bag which holds no more than 4 fruits is commonly used by pickers. Falling causes bruising and later spoiling. When low fruits are harvested with clippers, it is desirable to leave a 4-inch (10 cm) stem to avoid the spurt of milky/resinous sap that exudes if the stem is initially cut close. Before packing, the stem is cut off 1/4 in (6 mm) from the base of the fruit. In Queensland, after final clipping of the stem, the fruits are placed stem-end-down to drain.
In a sophisticated Florida operation, harvested fruits are put into tubs of water on trucks in order to wash off the sap that exudes from the stem end. At the packing house, the fruits are transferred from the tubs to bins, graded and sized and packed in cartons ("lugs") of 8 to 20 each depending on size. The cartons are made mechanically at the packing house and hold 14 lbs (6.35 kg) of fruit. The filled cartons are stacked on pallets and fork-lifted into refrigerated trucks with temperature set at no less than 55° F (12.78° C) for transport to distribution centers in major cities throughout the USA and Canada.
YieldThe yield varies with the cultivar and the age of the tree. At 10 to 20 years, a good annual crop may be 200 to 300 fruits per tree. At twice that age and over, the crop will be doubled. In Java,, old trees have been known to bear 1,000 to 1,500 fruits in a season. Some cultivars in India bear 800 to 3,000 fruits in "on" years and, with good cultural attention, yields of 5,000 fruits have been reported. There is a famous mango, 'Pane Ka Aam' of Maharashtra and Khamgaon, India, with "paper-thin" skin and fiberless flesh. One of the oldest of these trees, well over 100 years of age, bears heavily 5 years out of 10 with 2 years of low yield. Average annual yield is 6,500 fruits; the highest record is 29,000.
Average mango yield in Florida is said to be about 30,000 lbs/acre. One leading commercial grower has reported his annual crop as 22,000 to 27,500 lbs/acre. One grower who has hedged and topped trees close-planted at the rate of 100 per acre (41/ha) averages 14,000 to 19.000 lbs/acre.
RipeningIn India, mangos are picked quite green to avoid bird damage and the dealers layer them with rice straw in ventilated storage rooms over a period of one week. Quality is improved by controlled temperatures between 60° and 70° F (15° -21° C). In ripening trials in Puerto Rico, the 'Edward' mango was harvested while deep-green, dipped in hot water at 124° F (51° C) to control anthracnose, sorted as to size, then stored for 15 days at 70° F (21° C) with relative humidity of 85% to 90%. Those picked when more than 3 in (7.5 cm) in diameter ripened satisfactorily and were of excellent quality.
Ethylene treatment causes green mangos to develop full color in 7 to 10 days depending on the degree of maturity, whereas untreated fruits require 10 to 15 days. One of the advantages is that there can be fewer pickings and the fruit color after treatment is more uniform. Therefore, ethylene treatment is a common practice in Israel for ripening fruits for the local market. Some growers in Florida depend on ethylene treatment. Generally, 24 hours of exposure is sufficient if the fruits are picked at the proper stage. It has been determined that mangos have been picked prematurely if they require more than 48 hours of ethylene treatment and are not fit for market.