INTERNATIONAL JOURNAL FOR INNOVATIVE RESEARCH IN MULTIDISCIPLINARY FIELD

Abstract: Combretum indicum is a dichogamous and self-incompatible plant. The flowers have a white corolla at anthesis. The petals change colour gradually with the progression of anthocyanin accumulation and turn pale pink, then intermediate pink and lastly deep pink. Different pollinators visit the flowers at the different colour stages. In the present investigation the pH of the petal extract, the percent pink cells in the upper epidermis of the petals, and the photosynthetic pigments chlorophyll a, chlorophyll b and carotenoids in the petals have been studied at the four identified flower colour stages. The pH of the petal extract did not change with the change in flower colour. The number of pink epidermal cells in the upper surface of petals increased from zero to 93% as the petals passed from the white to deep pink stage with the accumulation of anthocyanins, the principal anthocyanin being cyanidin 3-O-glucoside. The photosynthetic pigments chlorophyll a, chlorophyll b and carotenoids were present at all the four flower colour stages. The absorbance of chlorophyll a and chlorophyll b was the highest in the deep pink stage, and that of carotenoids was highest at the white stage. Chlorophyll b showed higher absorbance than chlorophyll a at all the four stages. We suggest that the antioxidant anthocyanin along with chlorophyll b and carotenoids protect the petals from oxidative damage, thus ensuring that the flowers do not wither for three days.