Ultrastructural studies of 'Kensington' mango (Mangifera indica Linn.) heat injuries.
Jacobi K. K., Gowanlock D.
Author Affiliation: Horticulture Postharvest Group, Queensland Department of Primary Industries, 19 Hercules Street, Hamilton 4007, Queensland, Australia.
HortScience 30 : 102-103
Abstract : Mangoes are heat-disinfested in many countries, but the treatment can result in a variety of fruit injuries. In this study, mature green mango cv. Kensington fruits were submerged in hot water at 46°C until the fruit centre reached 45°, and were then held for 30 min. The fruits were allowed to ripen for 7-10 days after the hot water treatment, and then damaged areas of skin and mesocarp tissue were prepared for observation by scanning and transmission electron microscopy. Heating-related injuries included rupturing of the patterned cuticle and exocarp and exposure of the underlying cells and hollow cavities (which varied in size and shape) randomly distributed within the mesocarp beneath the skin. Starch deposits were still present in the mesocarp parenchyma cells. The cell walls of damaged mesocarp parenchyma cells were convoluted and thickened in places. The injury suggested disruption of enzymes involved in carbohydrate metabolism.