Changes in the cuticular surface during the development of mango (Mangifera indica L.) cv. Kensington Pride

Abstract

The surface morphology of mango fruit, cv. Kensington Pride, was studied throughout fruit development to gain an understanding of the development of the cuticular structures. This was done to identify possible weaker points where water and chemicals may penetrate and lead to skin disorders. At anthesis, no epicuticular wax fine structure was evident on the flower ovary and the surface of the cutin layers was smooth and unbroken. By fruit set, a thick layer of flattened polygonal epicuticular wax scales was evident on the surface. When the fruit diameter reached approximately 3 mm the epicuticular wax scales had developed a series of slightly flattened radiating wax rodlets on their base and perimeter. At about 12 mm fruit diameter, the epicuticular wax scales with radiating rodlets began to fragment and the cutin layers began to crack, forming irregular cuticular platelets. At this stage, a third form of epicuticular wax was evident as small erect scales projecting from the cuticle surface, these became the dominant wax form in mature fruit. As the fruit developed, the number of cuticular platelets increased by subdivision and became a more regular pentagonal shape. The thinnest points of the cuticle were in the central cracks of the cuticular platelets. These cracks may be possible entry points for chemicals, leading to skin blemishing.