MOLECULAR-CLONING AND DETECTION OF CUCUMBER MOSAIC CUCUMOVIRUS CAUSING INFECTIOUS CHLOROSIS DISEASE OF BANANA USING DNA PROBES

Complementary DNA (cDNA) to RNA genome of cucumber mosaic cucumovirus- Banana (CMV-B) isolate was prepared, cloned into pUC 119 plasmid vecto r and transformed E. coli DH5 proportional to F'. A clone with 1521 an d 334 bp inserts was selected and used for probe preparation. In dot-b lot hybridization, the radioactive (P-32) probe (1521 bp) detected tot al nucleic acids extracted from CMV-B infected banana leaf up to 10(-4 ) dilution and viral RNA up to 40 pg level. The non-radioactive digoxi genin (DIG) probe (1521 bp) detected the virus in purified virus prepa ration up to 10 pg, isolated viral RNA up to 5 pg and in pseudostem sa p exudate and leaf extract of infected banana up to 10(-4) dilution. D IG probe appears better for routine large-scale detection of virus in banana.