Gladiolus, the queen of bulbous ornamentals is very popular perennial cut flower owing to its marvelous beauty, striking colours, various sizes and shapes of flower, variable spike length and long vase life. In this experiment corms of eight varieties of gladiolus (Yellow Golden, Nathan Red, White Friendship, Jester Gold, American Beauty, Red Majesty, Purple Flora and Algarve) were treated with gamma rays and the frequency and spectrum of morphological mutations observed up to three generations at Model Floriculture Centre, G.B. Pant University of Agriculture and Technology during2012-2015.
Uniform and healthy corms of eight gladiolus varieties were taken and irradiated with different doses (0, 25, 40, 55 and 70 Gy) of gamma rays from 60Co source and planted in open field condition in Randomized Block Design (RBD) with factorial concept. The outcomes indicated that the plant survival decreased after gamma irradiation and minimum survival (77.11%) was recorded at 70 Gydose. Differences in varietal response to different mutagen doses were clearly evident as all the varieties differed in the spectrum and frequency of induced mutations. In vM1generation maximum flower colour mutation frequency was recorded in variety Purple Flora followed by Algarve and White Friendship. Irrespective of varieties, among different doses maximum mutation frequency was recorded at 55 Gy. In vM1 generation, maximum mutation frequency (18.52%) was recorded in Purple Flora variety at 55 Gy gamma rays irradiation. Most of the mutants were in the form of chimera in vM1 and few disappeared in vM2 whereas most of the mutants isolated in vM2 generation were solid mutants. A wide spectrum of colour was observed in treated plants and in general variants were lighter in colour than the original variety. Sixteen mutants, isolated from three varieties of gladiolus (White Friendship, Purple Flora and Algarve) were planted to raise vM3generation and out of these twelve were found stable for their colour.