Floral and reproductive biology of Sarpagandha <i>Rauvolfia serpentine</i> (Gentianales: Apocynaceae) in semi-arid environment of India

Sarpagandha plant Rauvolfia serpentina (Linn.) Benth., ex Kurz bears small, tubular white to pinkish flowers with gamopetalous corolla, containing nectar deep at the base of the corolla tube. Psychophilous mode of pollination appears to be prevalent. Flowering occurs during two summer months. Anthesis takes place in the morning when atmospheric temperature ranges from 25-29 0C, and anther dehiscence from 28-31 0C. Flower longevity is for a little more than two days. Nectar is produced on both the days of flower opening, and over a wide range of ambient temperature (29-44 0C). Flowers are protogynous preventing selfing. Pollen viability and stigmatic receptivity are for a short duration. When compared with the absolute reproductive potential, the realized reproductive potential is very low