Seasonal variation in the Shoot- Regeneration potential of the nodal explants of rosa setigera

The present paper reports seasonal variation in the regeneration potential of nodal explant of Rosa setigera over MS medium. We evaluated the shoot regeneration potential of the explants harvested from mature plants viz. shoot-tip, nodal segment (1.5cm), internodal segment (1.5cm) and leaf disc. The explants were harvested in rainy, winter and summer seasons and inoculated over MS medium fortified with various combinations of NAA, 2,4-D, BAP and kinetin. Among the explants, only nodal segments harvested in rainy and winter seasons induced microshoots. The response of explant varied with the concentration and combination of plant growth regulators and the season of harvest. The best response, in terms of multiple shoot induction, by nodal explants was exhibited over the medium fortified with 2.2M BAPin rainy season and 0.5M NAA+ 8.8M BAPin winter season.