Variation in the leaf chlorophyll contents in relation to leaf position and stages of berry growth in Thompson Seedless grape (Vitis vinifera L.)

Abstract

In order to identify the leaves with less photosynthetic ability and to provide a basis for leaf removal during the fruiting season to promote light interception and consequently berry coloration, variation in the chlorophyll contents of the leaves of Thompson Seedless grape at different nodal regions and stages was studied. Chlorophyll 'a' content 20 days after anthesis was low. Chlorophyll 'b' contents were low after 40 days of anthesis and in the leaves at the apical regions. Total chlorophylls did not differ with the leaf positions, while they decreased 40 days after anthesis. Substitution mechanism between the chlorophyll fractions was observed. The ration of chlorophyll 'a' to 'b' was highest in the leaves at the most apical region and after 40 days of anthesis. These observations indicated that the photosynthetic ability of the leaves at all nodal positions is same and goes down after 40 days of anthesis. Hence, any leaf can be eliminated 40 days after anthesis, if required.