Investigation on the reaction of Iranian oriental and semi oriental tobacco genotypes to Potato Virus Y (PVY) under controlled conditions

Potato virus Y (PVY) as one of the serious diseases on tobacco (Nicotiana tabacum L.), reduces leaf yield and its quality. Use of re-sistant genotypes is being considered as the most effective, economical and a safe way to reduce damages of the virus. In the present study, the response of 90 oriental and semi-oriental tobacco genotypes was evaluated against PVY using randomized complete block design with three replications under controlled conditions. Each replicate consisted of 6 seedlings. The leaves of each genotype were inoculated mechanically via rubbing me-thod at 4-6 leaf stage with PVY. Four weeks following inoculation, the studied genotypes showed different severity symptoms associated with PVY. ELISA assay were ap-plied on the inoculated plants by the indirect method using the polyclonal antibody specific to PVY. Optical density value of each infected sample was read at 405 nm using an ELISA reader. Analysis of variance on ELISA data showed significant differences among geno-types for concentration of PVY. Results re-vealed that 'Erzeogovina' genotype with OD=0.68881 contained the highest virus con-centration whereas the 'KB101' genotype with OD=0.0005 contained the lowest virus con-centration. The differed reactions of geno-types to PVY virus encourage the use of re-sistance genetic resource for the reduction of disease damages.