Distinguishing Isolates ofPeronospora tabacinafrom Geographic Regions Utilizing Tobacco Leaf Disks and Fluorescence Microscopy

Biological Characteristics and Assessment of Virulence Diversity in Pathosystems of Economically Important Biotrophic Oomycetes

“…These pathotypes would probably be elevated to species using modern molecular assessment tools. Wigelsworth et al (1994b) also described pathotypes based on germination percentages of sporangia from Mexico, the USA, and Bulgaria on leaf surfaces of various cultivars of tobacco. In Europe, Tuboly (1966) and Jankowski (1972) reported a physiological race (PT2) that infected N. debneyi, whereas the previous race (presumably PT1) did not.…”

“…However, Inter-Simple Sequence Repeats (ISSRs), a technique that targets multiple anonymous amplification sites were used to examine isolates differing in fungicide sensitivity (Zipper et al, 2009). Two of these amplicons were characterized (specific primers developed for these regions) and Tuboly, 1966;Jankowski, 1972OPT-1 (1980 Oxford, North Carolina, (USA) Race Todd, 1982 BPT (1963) American common, Fort Detrick, (Beltsville), MD (USA) Race Trigiano and Spurr, 1987 KPT-1 (1979) Kentucky (USA) Race Cohen and K uc, 1981 Undesignated North Carolina (USA) Races Bruck et al, 1982TX79 (1979 Texas (USA) Race Reuveni et al, 1988KY79 (1979 Scott Co., Kentucky (USA) Pathotype Reuveni et al, 1988;Wigelsworth et al, 1994aTx83 (1983 Uvalde Co. Texas (USA) Pathotype Wigelsworth et al, 1994bMx87P (1987 Papantla, Mexico Pathotype Wigelsworth et al, 1994bMx87S (1987 Veracruz, Mexico Pathotype Wigelsworth et al, 1994bBul88 (1988 Gotche, Delcher, Bulgaria Pathotype Wigelsworth et al, 1994bMetalaxyl-tolerant (2002-2011 Throughout Europe, but mostly Germany and France Race Spring et al, 2013Metalaxyl-susceptible (2002-2011 Germany, Spain and Eastern Europe Race Spring et al, 2013 reliably differentiate between metalaxyl-sensitive and -tolerant phenotypes of the pathogen. A specific and accurate genetic marker of fungicide sensitivity permitted monitoring for the presence and frequency of the phenotypes from year-to-year, as well as selecting isolates for studies on virulence and pathogen fitness.…”