Identification of microsatellite markers linked to Potato Virus Y (PVY) resistance genes in tobacco using Bulk Segregated Analysis (BSA) method

One of the most important viral diseases causing damage on tobacco is Potato Virus Y (PVY) which reduses the quality and quantity of tobacco products. The best way to control the disease is use of resistant cultivars. Molecular markers are used to label resistance genes in breeding programs. To determine the microsatellite markers linked to PVY resistance genes in tobacco, this research was conducted in Tirtash Tobacco Research Center, Behshahr, Iran. In the first year, VAM (a resistant cultivar) was crossed with K326 (a susceptible cultivar). F1 seeds were plants and F2 seeds were obtained. F2 plants were transplanted in farm and inoculated with a pure isolate of PVY strain O. Area under disease progress curve (AUDPC) was calculated as phenotypic evaluation. To confirm resistance and susceptibility of the used cultivars’ ten plants of each cultivar were tested by ELISA and resistant and susceptible plants were selected. Using 100 SSR pair primers and BSA method, microsatellite markers linked to PVY resistance genes were determined in resistant and susceptible bulks and in F2 populations. Three primer compounds PT30002, PT20165 and PT20357 produced polymorphism on DNA of resistant and susceptible bulks. These primers were also on single plants of two bulks and F2 populations and the data were analyzed. Markers distance from resistance genes was determined by Mapmaker ver.3.0 software. Based on the results, PT3 marker was located on 17.5 CM and PT1 and PT2 on 18.1 and 37.4 CM distance from resistance gene.