Cytogeographical studies in the genus Ranvolfia with special Reference to the factors influencing the alkaloid content in R.Serpentina Benth.

The study deals with the morphology of five Indian species including 38 geographical races. The species studied are R.serpentiana Benth, R.densiflora Benth, R.micrantha Hook , R.beddomei Hook and R. canescens Linn. Seven geographical races of R.Serpentina Benth are grown under identical environment. It reveals that there is a great variation in the percentage of their alkaloids. The study also reveals that clayey or sility loam of north India is more suitable for the production of alkaloid content in R.Serpentina, than the laterite soils of South India. Chromosome study of Indian Raurolfia`s show that R.Serpentina Benth and R.microntha Hook are diploids with 2n=22 and R.Densiflora Benth a natural tetrapoid with 2n=44.R. Canescens Linn is tetrapoid and hexaploid with 2n=44 and 66. Meiotic studies showed the formation of 11 bivalent in diploids and 22 in tetraploids