No abstract

Multiple shoot formation from the medicinal plant Plumbago rosea Linn. was induced on callus from stem segments on Murashige & Skoog media containing auxin and cytokinin. 2,4-D (2.5 mgl ~) and kinetin (1.5 mgl -t) added to the media gave best callus production, while BAP (2 mg 1 -j) plus NAA (1.0 mg 1 -~) induced shoot formation from that callus. Numerous shoots with roots could be produced by transferring shoots to media containing I BA (1.5 mg 1-~). Regenerated plantlets were transferred to pots and 60% survived.

No abstract

The tropical rain forests of South India are very rich in pteridophytes.The cytology of about one hundred and eighty species of leptosporangiate ferns indigenous to this area has already been reported (ABRAHAM et al. 1962;BIR 1965; KuRIACHEN 196 7 ). The results of cytological observations hitherto unrecorded from this area are presented here.

Detailed karyomorphological analysis of a species (Viscum capitellatum Sm.) in the family Viscaceae is reported for the first time. The exceptionally large chromosomes in V. capitellatum probably represent the largest chromosomes in dicot angiosperms. The chromosome number of the species has been found to ben= 10 and 2n = 20. One pair of the chromosomes is heterochromatic. It is suggested that unequal crossing over of a segment between the homologous chromosomes has resulted in one duplicate chromosome and the other deficient.