VIEW ARTICLE

Etiology

Identification and Nutritional Differentiation of the Erwinia Sugar Beet Pathogen from Members of Erwinia carotovora and Erwinia chrysanthemi. S. V. Thomson, Department of Plant Pathology, University of California, Berkeley 94720, Present address: Department of Biology, Utah State University, Logan 84322; D. C. Hildebrand(2), and M. N. Schroth(3). (2)(3)Department of Plant Pathology, University of California, Berkeley 94720. Phytopathology 71:1037-1042. Accepted for publication 24 December 1980. Copyright 1981 The American Phytopathological Society. DOI: 10.1094/Phyto-71-1037.

A disease of sugar beet denoted by soft rot and vascular necrosis is caused by a distinct group of Erwinia carotovora strains and is named Erwinia carotovora subsp. betavasculorum subsp. nov. A comparative study was made of the nutritional properties of 99 strains of identified and unidentified soft-rotting Erwinia species from several hosts, including sugar beet. Seventy-one strains were placed either in E. carotovora subsp. carotovora, E. carotovora subsp. atroseptica, or E. carotovora subsp. betavasculorum subsp. nov., or one unclassified group in this species depending on similarities of nutritional properties. Nutritional and physiological tests useful for distinguishing subspecies of betavasculorum from one or more of the other Erwiniae include: growth of α-methylglucoside, d-lactate, ethanol, l-lysine, maltose, palatinose, d-asparagine, and ethanol; either no, or very slow, growth on cellobiose, galacturonate, melibiose, malonate, and raffinose; no indole or phosphatase production; no gas from glucose; resistant to erythromycin; growth at 36 C; and the production of reducing substances from sucrose. Twenty-eight strains were placed into E. chrysanthemi and divided into six subdivisions. These six subdivisions corresponded to previously described species varieties or formae speciales and are generally equated with the host from which they were originally isolated.