Molecular Virology Laboratory, National Botanical Research Institute, Lucknow-226001.
Abstracts of Research Papers Presented during the National Symposium of Indian Virological Society at Unit of Plant Virology, Division of Plant Pathology, Indian Agricultural Research Institute, New Delhi-110 012, October 14–1.
Catharanthus roseus is a medicinal plant used worldwide for its antidiabetic and anticancerous activities. C. roseus is known to be susceptible to phytoplasma infestations. The phytoplasmas are pleomorphic, wall-less prokaryotes found in the phloem of many other affected plant species. Phytoplasma induces symptoms of virescence and phyllody or reduced flower size and colour.
Shoot-apex cultrues of phytoplasma infectedplants of C. roseus were aseptically established on MS media fortified with different concentrations of auxins and cytokinins. Multiple shoots were emerged out from explants in 4 weeks. Roots were induced in these cultures in MS media containing reduced concentration of salts, sucrose and low concentration of a-naphthalene acetic acid. After hardening for about a week in Hoagland solution, the plants were transferred to pots under glass house conditions.
For producing phytoplasma-free plants, the shoot-apices from either in vitro-raised or field grown/glass house maintained phytoplasma infected plants, were cultured in MS medium containing different concentrations of oxytetracycline (20–100 mg/l). The presence/absence of phytoplasma in in vitro-raised plants was demonstrated by nested PCR. The cultures raised on 50 mg/l oxytetracycline were apparently found phytoplasma-free. Further, the results of multiple shoot induction, effect of oxytetracycline on growth and development of explants and PCR analysis will be discussed.
