Division of Biotechnology, Indian Institute of Horticultural Research, Hessaraghatta, Bangalore.
The viral disease caused by Papaya ring spot virus (PRSV) has become a serious threat to papaya cultivation worldwide. The coat protein (cp) gene from the local (Bangalore) isolate of the virus was cloned and sequenced. A plant expression cassette was developed and the plasmid construct was electroporated into the growing meristem of seedlings of papaya varieties Solo and CO-7. Studies on transient gene expression in detached leaves of papaya and tomato were carried out to validate the clone. The plasmid DNA (pAVCP-PRSV) was electroporated into leaf disks of papaya and tomato. Transient expression of PRSV-CP mRNA was studied at 1, 4, 8 and 16 hour intervals through RT-PCR followed by dot blot of the PCR product