Common scab susceptibility of 24 most popular potato cultivars in USA, utilizing a greenhouse assay with three different pathogenic Streptomyces strains (species) Increasing disease score 0 100 200 300 400 500 600 0 100 200 300 400 500 600 0 100 200 300 400 500 600 Norland No data R Norkotah (ND) R Norkotah (ID) Shepody R Norkotah (ND) Ranger Russet No data R Norkotah (ID) R Norkotah 296 R Norkotah ID Norkotah 3 Red La Soda Shepody Yukon Gold Norkotah 8 Shepody Premier Russet Alturas Norkotah 8 Pike Premier Russet Dk Red Norland Norland Yukon Gold Norkotah 3 Russet Burbank Red La Soda Atlantic R Norkotah 296 Russet Burbank Ranger Russet Gold Rush Dk Red Norland Red La Soda Alturas R Norkotah 296 Megachip Snowden Superior Atlantic Superior Yukon Gold Snowden Russet Burbank Megachip Silverton russet Megachip Rio Grande Yukon Gold ME Dakota Pearl Atlantic Canela russet Dakota Pearl Premier Russet Yukon Gold (ID) Norkotah 3 Norland Dakota Pearl Snowden Silverton russet Superior Canela russet Dk Red Norland Pike R Norkotah ND Yukon Gold (WI) S. scabies Blazer Russet S. stelliscabiei Gold Rush S. species IdX Pike Rio Grande Alturas ME01-11h NY02-1c ID01-12c Gold Rush Yukon Gold 5.1e8 CFU/pot Norkotah 8 1.2e9 CFU/pot Blazer Russet 1e9 CFU/pot Ranger Russet Silverton russet Rio Grande Canela russet Blazer Russet Cultivars are listed along the left side of graphs, ranked by disease severity, with most susceptible at the top and most resistant at the bottom. Disease score is a combination of type of lesion (surface, pits or raised lesions) and amount of surface area affected. Amount of pathogen applied was similar for all 3 Streptomyces strains, and is shown under isolate name on graphs. The Streptomyces isolates used are S. scabies ME01-11h, the most aggressive of the strains, isolated in northern Maine but found in many locations, particularly in the Northeast and Mid-West; S. stelliscabiei NY02-1c, which is intermediate in aggressiveness and is found in numerous locations primarily in the Northeast and Mid-West; and S. species IdX, the least aggressive of the strains, characteristic of Idaho but found in many locations. Some cultivars change in ranking in response to different Streptomyces strains (e.g. Alturas, Pike). Experimental details of screening top 24 potato cultivars for common scab response in greenhouse assays in 2011. Mean Mean Mean mean Pathogenic Inoculum mean Les severity mean quick tubers surface Streptomyc density/ Type (LT) score incidence score scored/ area (SA) es isolate pot all reps LT*SA all reps (0 -6 scale) rep all reps all reps ME01-11h 1e9 3.16 8.7 3.9 37.3 176.3 90.3 NY02-1c 5.1e8 1.86 7.4 2.2 21.1 71.7 79.5 ID01-12c 1.1e9 1.64 7.5 2.2 10.2 30.4 73.1 .