Varietal and seasonal variations in in-vitro rapid propagation of Rosa hybrida

The in-vitro response of axillary buds was more in winter than in summer rose cultivars. However, the requirement of growth regulators was same both in summer and winter. Cultivars Priyadarshini and Raktagandha can be classified into one group and Raktima and Arjun as another based on their response to different growth regulators regimes. Keeping in view the high contamination rate, low rate of proliferation, extended duration for proliferation, initiation of cultures during summer months appears to be economically non-viable. The differential response of cultivars to different growth regulator regimes needs to be investigated further.