Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 7/18/2007
Publication Date: 7/18/2007
Citation: Cavin, C.A., Bruckart, W.L. 2007. Host range determination of Uromyces salsolae from Russian thistle. Phytopathology. 97(7, Supplement): S19
Technical Abstract: Salsola tragus (Russian thistle) is a major weed pest in the western United States. An isolate of Uromyces salsolae from Greece currently is a candidate for biological control of S. tragus. Risk assessment to determine potential non-target susceptibility involved inoculation of 53 species with 0.5 mg uredinia per plant. Over half (42) of the test species were from the Chenopodiaceae, including three cv of Beta vulgaris (Table Beet, Sugar Beet, Chard) and one cv of Spinaca oleracea (Spinach). Inoculated plants were incubated in a dew chamber at 18 C for two days. The first 18 hours were in darkness followed by 8 hours of light, followed by 18 hours of darkness. Plants were then placed on a greenhouse bench at 21 - 25 C with natural light supplemented to give a 16 hr photoperiod and observed for symptom development. All individual S. tragus plants were infected. Minor, non-target infections (macroscopic symptoms) were noted on five species, all in the Chenopodiaceae, including Bassia hyssopifolia, Halogeton glomerratus, Salicornia virginica, Salsola soda, and Suaeda californica. No infection was observed on Salsola tragus Type B.