APS Homepage

POSTERS: Population biology and genetics

Characterization of pathogenic Streptomyces spp. causing scab in Michigan potato, turnip and beet production.
Saltanat Mambetova - Michigan State University. Benjamin Werling- Michigan State University, Katlin Blaine- Michigan State University, Noah Rosenzweig- Michigan State University, Mary Hausbeck- Michigan State University, Ray Hammerschmidt- Michigan State University

Pathogenic Streptomyces spp. causes scab disease in a number of plants including potato, turnip and beet. Michigan is a national leader for growing potatoes for chip production and for root crop production including ranks first in turnip acreage in the US, and sixth for beet acreage. Common scab of potato and scab in turnip and beet is caused by several Streptomyces species. The objective of this study was to characterized plant-pathogenic Streptomyces spp. associated with common scab infected potato, turnip and beet roots harvested in Michigan. A total of 151 putative isolates, 39 from turnip roots, 13 beet roots, and 99 from potato tubers were successfully isolated. The isolates were identified by morphological and molecular methods and phylogenetic relationship was determined between isolates. Preliminary results showed out of 151 isolated 48 isolates that caused pitted and surface lesions have genes encoding for thaxtomin synthase (txtA and txtAB), tomatinase (tomA) and a necrosis protein (nec1). Maximum-parsimony analysis of 3 loci revealed three similarly clustered groups, with some exceptions. Preliminary results from isolates recovered from turnip and potato from scab lesions shared similar molecular characteristics and grouped together in phylogenetic analyses. Whereas, potato isolates recovered from pitted lesions shared similar molecular and morphological characteristics and grouped together based on phylogeny.