Main objective of our study is to describe cytological behavior in Sarcostemma viminale (L.) R.Br. and Ceropegia bulbosa Roxb. from Thar Desert of Rajasthan, India. The family Asclepiadaceae (approx. 290 genera) is a homogeneous complex with complicated floral structure. Little cytological data is available on most of the species in the family and both the plants under study are endangered. The present study deals with Sarcostemma viminale (L) R.Br. that is a shrub while Ceropegia bulbosa Roxb. var. bulbosa and var. lushii is a herb of milkweed family. Both plants are xerophytic and show CAM features. They grow in association of other shrubs. The microscopic slides of meristamatic cells were prepared by using the classical method and aceto-carmine staining. 2n═22 was observed in both the plants. Basic chromosome number in the family is frequently X=11. Polyploid taxa are also found in most of the genera in this family.
