Cuticular Transpiration and Wax Structure and Composition of Leaves and Fruit of Vitis Vinifera

Abstract

SummaryThe fine structure of the surface wax of leaves of sultana vines (Vitia viiUJera var. sultana) has been examined using the carbon replica technique. Leaf wax was found to be morphologically similar to the wax on the surface of grapes and to consist of a series of overlapping platelets. A brief period (30 sec) of exposure to light petroleum vapour disorganized the platelet structure of both leaf and fruit wax. This treatment markedly increased the cuticular transpiration of both fruits and leaves. The results are discussed in relation to the known chemical composition of these waxes. It is suggested that the surface wax, which consists of overlapping platelets that are hydrophobic in nature, may be important in controlling cuticular transpiration in both the fruit and leaves of grape.vines.

The Surface Wax of Several Grapes in Japan

“…On the other hand, Possingham et at. (8) have described that the spray of fungicides containing detergents affects the wax structure. The precise reason for the reduction of the surface wax by the delay of postbloom GA application in this study is not clear but it seems that a detergent, Aerol OP contained in the GA solution may play a Comparison of wax at maturity tivars in Japan.…”

“…The soft wax of `Delaware' was further examined by GLC for the long-chain alcohols which were reported to be its main components (5,8). As shwon in Fig.…”

“…The waxes were extracted at room temperature with petroleum ether and chloroform as suggested by Grncarevic and Radler (5) and Possingham et al (8). Five hundred to 1, 000 berries from 10 clusters in the early stages of berry growth and 120 to 200 berries from 5 to 6 clusters in the middle and late stages were used for the extractions.…”

“…Since this type of surface structure is a strong barrier to the transpiration from berries, the chemical nature and fine structure of the wax have been investigated by many workers in `Thompson Seedless (Sultana)' , the most extensively grown raisin grape in the world (1,2,5,6,7,8,9,10,11). On the table grape cultivars, however, there have been hardly any detailed reports on them.…”

A Comparative Anatomical Study of the Grapevine Shoot: I Epidermis

“…The cuticle of Vitis consists of layers of soft wax containing alcohols, aldehydes, fatty acids, esters and hydrocarbons (Chambers & Possingham, 1963;Possingham et al, 1967;Gentlini, 1969;Radler, 1970). According to Radler (1970) the cuticle differs from that of other plant species in that it contains no olei:nolic acid.…”