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In this study, karyotypes of three taxa in the genus Argyreia Lour. were examined. The chromosome counts for A. osyrensis and A. setosa were reported for the first time while somatic chromosome count of A. cuneata was confirmed. The three taxa studied were diploid with 2n = 2x = 30. Highest total chromosome length in Argyreia osyrensis was 54.25 μm with mean chromosome length (MCL) of 3.62 μm. The lowest in Argyreia setosa as 46.04 μm with the mean chromosome length of 3.07 μm. The karyotypes of the species were examined on the grounds of various karyotype asymmetry indices. Two of them, A. cuneata and A. osyrensis fell in the 3A while A. setosa belonged to the 4A category of Stebbins’ classification.

An in vitro micropropagation system has been developed for the Ceropegia anjanerica Malpure et al., a rare endemic plant species having ornamental as well as medicinal potential but a limited reproductive capacity. Axillary bud explants were cultured on Murashige and Skoog medium supplemented with 6-Benzylaminopurine, Thidiazuron and 6-Furfurylaminopurine along with combination of Indole-3-Butyric Acid. Although all concentrations showed multiple shoot formation, the best results (8.0 ± 0.5) were achieved with MS + 6-Benzylaminopurine (8.87 µM) + 6-Furfurylaminopurine (18.58 µM). Half strength Murashige and Skoog medium fortified with Indole-3-Acetic Acid (8.56 µM) showed good rooting response (4.0 ± 0.7). Well grown plantlets hardened, acclimatized and established in greenhouse exhibited 78 % survival.

A new species of Hubbardia Bor from the northern Western Ghats is described and illustrated. The new species differs from H. heptaneuron by its glumes with long tubercle-based hairs and two stamens in the fertile floret.

Factors affecting in vitro propagation were evaluated for Ceropegia attenuata Hook., an endemic and endangered plant having ornamental potential but a limited reproductive capacity. Rapid shoot multiplication from nodal explants was established using varying concentrations of cytokinins and auxins either alone or in combinations. The highest frequency of shoot induction was achieved when nodal explants were inoculated on Murashige and Skoog (MS) medium supplemented with 13.31 μM 6-benzylaminopurine with a mean of 12.9 ± 0.5 shoots per explant. High concentrations of TDZ (6.81–11.35 μM) and KN (6.78–11.61 μM) resulted in stunted and vitrified shoots. Factors implicated in the promotion of floral transition of the C. attenuata have been identified which are 4-amino-3, 5, 6-trichloropicolinic acid (picloram), 6-benzylaminopurine, sucrose and photoperiod. The highest frequency of flowering (100%) was obtained when axillary shoot explants were transferred to MS medium supplemented with picloram (4.14 μM) within 4 weeks of culture. Transfer of in vitro regenerated shoots to half strength MS medium with 2.46 μM indole-3-butyric acid (IBA) showed maximum root induction. The in vitro grown plantlets were successfully acclimatized in the glasshouse with 85% of survival and showed normal development. The developed protocol provided a simple, cost-effective approach for the conservation of endangered plant C. attenuata for replenishing its declining populations.

Callisia is a tortuous genus reported to show a wide range of chromosome counts. Present paper reports an unusual chromosome number 2n = 18 for C. fragrans, a number that is so far not known, not only in C. fragrans but also for the entire genus Callisia. The variable chromosome number and varied karyotype architecture is indicative of the fact that the genome of the genus Callisia may be still unstable and in constant evolution.