Submitted to: Annual Beet Sugar Development Foundation Research Report
Publication Type: Research Notes
Publication Acceptance Date: May 30, 2007
Publication Date: June 19, 2007
Citation: McGrath, J.M., Hanson, L.E., Panella, L.W. 2007. Cercospora Nursery. Annual Beet Sugar Development Foundation Research Report. p. D4-D14. Technical Abstract: The cooperative BSDF Cercospora leaf spot nursery was moved from the historic Ft. Collins, CO ARS site to the East Lansing, MI ARS location, and conducted at the Saginaw Valley Bean and Beet Farm. Commercial entries (96 lines) were planted in 2-row plots, each 15 feet in length, replicated four times in a randomized complete-block design in 30-inch rows. USDA-ARS seed (117 entries) was similarly planted with the exception that the experimental design was single rows with three replications, and all but East Lansing seed was treated to minimize the impact of seedling disease. Emergence was very good to excellent, and plots were blocked to 4-inch spacing and doubles were removed where necessary. Plots were inoculated with a spore suspension spray in the third week of July, shortly before complete row closure. Plots were initially viewed for evidence of disease on July 27, at which time a few lesions could be observed in the spreader rows and some of the more susceptible entries, and similar observations were noted on August 1. By August 9, the disease had dramatically spread due to the high night temperatures and humidity. In general, most of the commercial materials submitted were susceptible or highly susceptible, and a range of reaction was observed among the breeding materials submitted by USDA cooperators.