Study On The Detection Of Chrysanthemum Viruses And The Method For Elimination Of Virus By Meristems Culture

Chrysanthemum, derived from china, is one of ten traditional famous flowers in China and four most important cut flowers in the world. It was cultivated throughout China. Since Chrysanthemums are commonly propagated by means of vegetative, they are subject to a large number of virus and viroid diseases. The infected plants may show symptoms such as mosic disease, blocky, malformation, stunt but sometimes asymptomatic. The viruses would be accumutated with the plants propagating, which is a potential threat to chrysanthemum production. Therefore, a rapid, sensitive and accurate detection and identification method of chrysanthemum viruses should be developed to prevent the virus and viroid spread widely. In practice, the control of chrysanthemum viruses is achieved through the production of healthy chrysanthemum. The purpose of this study was to explore the method of the detection and identification of viral pathogens infecting chrysanthemum and elimination of virus. The main results were followed:(1) The method of DAS-ELISA and RT-PCR were used to detect the infected chrysanthemum plants in the Chrysanthemum Germplasm Resource Preserving Centre, Nanjing Agricultural University, China, the results showed that CVB and TAV can be detected by DAS-ELISA, while the RT-PCR can detect the viruses such as CVB, TAV and viroids of CSVd, CChMVd;(2) A multiplex RT-PCR assay to detect CVB, TAV, CSVd and CChMVd were established and the assays were performed to detect the known viruses naturally infected plants successfully;(3) The sensitivity of DAS-ELISA, single RT-PCR, multiplex RT-PCR were compared. The results showed that the detection limit of single RT-PCR was fg, which is100times more sensitive than that of DAS-ELISA, the multiplex RT-PCR has the similiar level with the single one;(4) Different sizes of shoot tips were cultivated in medium for the elimination of CVB. The virus-free plants were confirmed by RT-PCR. The results showed as the size increased, the number of live plant rate increased, but the virus-free plants rate decreased. The method of making virus-free plants by using secondary meristem tip culture was much better that the traditional method.