EFFECT OF GAMMA IRRADIATION ON MORPHOLOGICAL CHARACTERS OF MARIGOLD (TAGETES ERECTA L.)

Seeds of marigold cv. ‘Pusa Narangi Gainda' were treated with different gamma irradiation treatments viz, control, 25 Gy, 50 Gy, 75 Gy, 100 Gy, 125 Gy and 150 Gy and evaluated for various morphological characters. Reduction in survival percentage, plant height, number of branches and plant spread was observed after irradiation and with increase in exposure of gamma rays. Early flower bud initiation and flower opening was observed in lower dose of gamma rays. Flower diameter, number of flowers and length of peduncle was significantly highest at the lowest dose of gamma irradiation. The stimulatory effect of gamma irradiation was observed at 25 Gy in almost all the characters, though the intensity of inhibition increased with increasing exposures of gamma rays. On the basis of present observation, it may be concluded that irradiation of gamma rays of 25 Gy was found to be beneficial for growth and flowering characters in African marigold cv. Pusa Narangi Gainda