NEW CHRYSANTHEMUM VARIETIES DEVELOPED BY RADIATION BREEDING AND MICROPROPAGATION

Mutation breeding by radiation, an agricultural application of nuclear technology, has been widely utilized by at least 37 countries to develop new varieties with improved agricultural characteristics especially the stress resistance and quality of product.

Chrysanthemum (Dendranthema morifolium L) is a beloved flower which has been cultivated for 3 000 years. There are now more than 3 000 varieties of chrysanthemum in China, but some of which degraded due to the infection of viruses. Being a cross-pollinated species, some new chrysanthemum varieties with improved floricultural characteristics were developed by hybridization breeding but because some chrysanthemum varieties blossomed with developed ligulate flower and completely degenerated tubular flower, and the anthesis period are in deep winter which limited the seed development, it was difficult to breed new varieties by hybridization. Most cultivated chrysanthemum are polyploid of genetically heterogeneity, mutants with flower colour and shapes of flower, corolla and types of chimera could be easily induced by radiation, the fixation and propagation of mutation by plant tissue culture could greatly improve the efficiency of chrysanthemum breeding. Here we report some new chrysanthemum varieties developed by radiation breeding and micropropagation.