Abstract:
Among the highly fragrant Rosa species, Rosa gruss an teplitz and Rosa centifolia have high value in terms of
commercial importance and economical trade. However, the absence of floral diversification and diversity in color patterns in these species acts as limiting factors in floriculture trade of these species. In the present study, we aimed to induce mutations using gamma radiations up to 120 Gy to observe the rate and the correlated effects on the several plant traits in micropropagated shoot tips of Rosa gruss an teplitz and Rosa centifolia. Irradiated shoot tips were micropropagated for one culture cycle and were acclimatized in a green house after in vitro rooting. Plants of irradiated population at 60 and 30 Gy showed 78.12 and 38.50% less culture rooting % age as well as 23.82 and 7 % less flower size as compared to non irradiated population of Rosa gruss an teplitz and Rosa centifolia respectively. Moreover, flower color component a* (+ redness – green, 36.16 and 27.16) and chroma (37.77 and 27.5) depicted minimum while L* (Lightness, 45.12 and 76.64), b* (+ yellow – blue, 10.69 and -4.14) and hue angle (17.1 and -8.58) maximum value. Apart from these variations, mutants of
Rosa gruss an teplitz also produced variegated, pink color and different shape flowers. Genetic variations observed among the putative mutants of Rosa gruss an teplitz and Rosa centifolia were evaluated using twelve decamer RAPD primers. Phylogenetic inferences showed large genetic diversity in putative mutants as compared to mother plant.