Reproductive biology of Rauvolfia serpentina (L.) benth. ex kurz
摘要
Rauvolfia serpentina (L.) Benth. ex Kurz is a small perennial undershrub belonging to the family Apocynaceae of dicotyledonous. The plant has been documented in ancient Indian literature dating back to 1000 BC and is commonly referred to as Sarpagandha and Chandrika. This plant is highly significant in the field of medicine for its effectiveness in treating hypertension. The plant bears small, tubular, white flowers generally shaded with pink to violet colour with a gamopetalous corolla, containing nectar deep at the base of the corolla tube. Flowering occurs throughout the year but peaks from February to March and the middle of June to the middle of July. Anthesis started in the early morning between 05:30 and 07:00. But dehiscence of anthers took place on the next day of flower opening, between 07:00 to 08:00 h. Nectar secretion was found to be on both days of flower opening. Pollen viability ranges between 80 and 85% were observed and the receptivity of stigma was found to be highest on the day of anthesis between 07.00 and 13.00 h. Our study revealed that R. serpentina flowers are protogynous, preventing selfing, and preferentially cross-pollinated. Fruiting is poor due to the limitation of compatible pollens.