Evaluation of Relative Resistance of Tobacco to Potato Virus Y Using Microsatellite Markers (SSR)

Tobacco is one of the industrial plants which plays important role in economy and income of producer contries. Potato Virus Y (PVY) is one of Viral diseases causing the most damage on tobacco plants and reduces the quality and quantity of tobacco products. Severity of damage depends on different factors such as tobacco variety and time of infection. Potato Virus Y (PVY) is belonging to the Potyvirus genus that infecting Solanaceae plants, such as potato, tobacco and tomato. The best way to reduce damage this virus, is breeding resistant or tolerance cultivars to this virus. DNA markers Linked with resistance genes and have high polymorphism Like SSR markers can be helpful in breeding programs on resistant cultivars. This study was performed to evaluation of tobacco relative resistance to Potato Virus Y using Microsatellite markers (SSR). The implementation of this research, the VAM variety (resistant to PVY) was crossed with susceptible cultivar K326. F1 seeds were planted and F2 seeds were obtained in 2011. F2 seeds were transplanted in 2011 in Tirtash tobacco research farm. These plants were inoculated with pure isolates PVY strain O. Leaf samples were prepared based on field symptoms from 10 tolerant and 10 susceptible plants. All the samples tested with ELISA and resistant and susceptible genotypes were identified. Genomic DNA of resistant susceptible genotypes to PVY, were extracted separately to Dellaporta method. Then, 100 SSR markers were tested on two parental DNA. Results showed that among 100 pairs of primers used in this study, 28 primer pairs were able to show different model between the resistant and susceptible parents. In the next stage of the 28 markers were tested on sensitive and resistant bulk to identifying marker genes associated with resistance. It was found that three SSR markers PT30002, PT20165, PT20357 have the highest polymorphism and can be considered as genetic markers for screening resistance to PVY in tobacco.