Chrysanthemum (C. morifolium) improvement through mutation breeding and tissue culture technique

In this study the tissue culture of the growing parts of meristem tip, shoot tip and axillary bud of three varieties of chrysanthemum (Promenade, Cham rock and Klon dike) was conducted in the Murashige and Skoog (MS) medium with 1 mg/1 BA and 0.1 mg/1 NAA. To increase the number of tips and buds of the chrysanthemum plant, the cultures were exposed to different levels of acute irradiation at 5, 10, 20, 30 and 50 GY. The results indicated that the percent survival from irradiation of axillary bud, meristem tip, and shoot tip of the three varieties of chrysanthemum were 33.8, 32.8 and 23.8 percent, respectively for Promenade 31.9, 31.4 and 25.2 percent, respectively for level cham rock and 29.5, 29.0 and 24.2 percent, respectively for Klon dike. On the other hand, the 50 GY level of radiation produced a hundred percent mortality for the three varieties of chrysanthemums because the cultured parts were not able to survive the radiation level of 50 GY. The chrysanthemum buds that were irradiated and have survived were then propagated to increase their quantity for experimental use as M1V4 and were induced for root development in the MS (1962) medium with 0.3 mg/1 NAA. The ensuing plantlets that have roots by irradiation were planted in Mae Sa Mai Royal Project in Maerim district, Chiang mai province. It was observed that chrysanthemum plants that were irradiated at 5, 10, 20, 30 and 40 GY have greater frequency for mutation breeding in terms of the characteristic shape of chrysanthemum flower with the Promenade, Cham rock and Klon dike varieties at 13.0, 6.2 and 8.1 percent, respectively. As for the mutation breeding in terms of color, the frequency was 10.7, 7.9 and 8.3 percent, respectively for the three varieties. Their mutations can be used for propagating the chrysanthemum flower through cutting for another process of plant testing in the investigation of the fluctuations in M1V5 and propagation was followed which is intended for agricultural extension in the future.