Studies the Cymbidium mosaic virus movement mechanism and establishment of a virus-induced gene silencing (VIGS) system

Cymbidium mosaic virus (CymMV) is a prevalent orchid virus and belongs to the genus Potexvirus in the family Flexiviridae (Adams et al., 2005b). Because the cultivation of orchids has become an important industry, CymMV is now a very economically important virus. Although potexvirus has been extensively studied, the study of CymMV remains focused on the isolate sequencing and detection. In my thesis, I have collected several CymMV isolates. Besides to develop the methods for detection of these isolates, I also utilized these isolates for basic and applied studies. In the first part of my thesis I established a system for the study of isolate-dependent host movement study. The studies revealed not only identify the factors involved in CymMV isolate dependent movement but also the molecular mechanism involved in CymMV movement. In addition, we utilized the collected symptomless CymMV isolates to develop virus-induced gene silencing (VIGS) vectors for orchid functional genomics studies. Beside the vector, we also develop a strategy to overcome the obstacles lie in the study of plants with long life cycle such as Phalaenopsis orchids. The results were detailed described in chapter 2 and 3 and published in two separated papers: Virology, 388:147-159 and Plant Physiol. 143:558-569.