CUCUMBER MOSAIC VIRUS IN NEW GUINEA IMPATIENS IN TAIWAN
New Guinea impatiens (Impatiens hawkeri), belonging to the family Balsaminaceae, is a popular ornamental plant for beds, pots, and baskets in Taiwan. In 2003, apparent mosaic symptoms were observed on leaves of New Guinea impatiens in the Taipei area. Extracts from these plants caused chlorotic lesions in leaves of Chenopodium quinoa. After three successive single lesion isolations in C. quinoa, a virus isolate, IH, was obtained. Back inoculation to healthy New Guinea impatiens seedlings revealed similar mosaic symptoms as field diseased plants showed. The results of inoculation to several indicator plants were similar to those of a previously reported Cucumber mosaic virus (CMV) isolate infecting New Guinea impatiens. In indirect ELISA, symptomatic plants were tested positive for CMV using a particular polyclonal antibody. For obtaining further molecular evidence of CMV, the 3 terminal region was amplified by RT-PCR from total RNA of inoculated Nicotiana benthamiana plants using two CMV RNA3 specific primers. A 1.0-kb fragment was amplified and cloned into pGEM-T® Easy vector. Three independent clones were sequenced and blasted in a database. The outcome indicated that the sequenced fragment is 1022-bp long containing the CP gene of CMV. The result clearly indicated that our IH isolate is an isolate of CMV. Further multiple sequence alignment of the CP gene with 15 other strains or isolates of CMV was performed. The IH isolate had the highest identity with Tfn and NT9 strains in amino acid as well as nucleotide sequences of the CP gene, suggesting it should belong into CMV subgroup IB. To our knowledge, this is the first report of natural infection of New Guinea impatiens by CMV in Taiwan.
Hu, W.C. and Chang, Y.C. (2006). CUCUMBER MOSAIC VIRUS IN NEW GUINEA IMPATIENS IN TAIWAN. Acta Hortic. 722, 241-246
Impatiens hawkeri, CMV, CP gene, phylogenetic analysis, subgroup IB