For establishing infection in a host plant, a natural vector is required for the transmission of the virus from an infected host plant to healthy plant. Alternatively, the susceptible host plant can be inoculated with cloned plant virus genome either mechanically or using Agrobacterium. For RNA viruses, full-length infectious cDNA clones are used for establishing infection. My current work entails the construction of an agroinfectious clone of Rice Tungro Spherical Virus (RTSV) and further examine the methods by which RTSV evades RNAi silencing response in rice.