Table beets (Beta vulgaris) are one of the most popular food items sold at local farmer's markets throughout the nation. Containing high levels of Vitamin C, iron and magnesium, table beets are savored for both their sweet roots and their attractive yet flavorful tops. In many areas, crop stand becomes an issue due to the susceptibility of young seedlings to damping-off, caused by Pythium spp. and Rhizoctonia, two genera of fungal pathogens that are ubiquitous in distribution. Foliarly, Cercospora leaf spot, incited by the fungal pathogen Cercospora beticola Fuckel, is widely regarded as the most important disease of beets worldwide. Favored by warm, humid conditions, Cercospora leaf spot is particularly a problem in the southeast U.S. While cultural characteristics and yield are typically the major factors in selecting which variety to plant, disease resistance should also be considered, particularly if grown for organic production. Field variety trials were conducted during 2012 and 2013 to assess the influence of seedling diseases on crop stand, early vigor and the susceptibility of beet foliage to Cercospora leaf spot. The experiments evaluated eight commercial beet varieties in a randomized complete block design with four replications. Standwas evaluated on a percentage basis by visually estimating the percentage of row occupied by the crop for each planted row. Vigor was assessed on a zero to five scale, with 0 = no vigor (dead),and 5 = high vigor. Cercospora leaf spot susceptibility was also assessed on a zero to five scale, with 0 = no disease (immune), 1 = highly resistant, 2 = resistant, 3 = moderately susceptible, 4 = susceptible, and 5 = highly susceptible. Varieties tested ranged significantly in root shape, top, and root color (Table 1). Red Ace, Kestrel and Cylindra provided the best stands with Red Ace and Kestrel producing the best early vigor. Varieties differed significantly in terms of susceptibility to Cercosporaleaf spot. The golden globe variety Touchstone Gold proved to be very resistant, with the maroon-leafed variety Bull's Blood also exhibiting excellent leaf spot resistance. All of the other varieties demonstrated some degree of leaf spot susceptibilitywith Detroit Dark Red and Ruby Queen being the most susceptible. Using a seedling drench with the fungicide Uniform at a rateof 0.34 fl oz/1000 ft of row significantly improved both stand establishment and plant vigor across all varieties. It is hoped that this study will provide growers with information useful in selecting varieties that best suit their needs. For organic growers who may have limited tools to manage Cercospora, Touchstone Gold and Bull's Blood offer good leaf spot resistance, reducingthe need to spray. For conventional growers interested in good stands, Red Ace and Kestrel demonstrated much promise.
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