Anatomical investigation of lenticel development and subsequent discolouration of 'Tommy Atkins' and 'Keitt' mango (Mangifera indica L.) fruit.

摘要

Post-harvest discolouration of mango fruit lenticels is a major problem and detracts from the aesthetic value of the fruit. It is unacceptable to consumers, consequently depreciating the economic value of the fruit. To determine the causes and timing of fruit lenticel discolouration, fruit anatomy from anthesis up to maturity was examined microscopically. Lenticels differentiate from existing stomata that lose their function and protrude above the fruit surface as a result of rapid anticlinal cell divisions in the epidermis of the exocarp. Based on a comparative study between different mango cultivars and mature marula fruit, it seems as if the absence of a cork cambium and cork cells in the mango lenticel could be one of the most important reasons for lenticel discolouration. An interaction between naturally occurring pigments and sap from the resin ducts in the exocarp appears to be another reason for lenticel discolouration.