Janis A. Fomba
Graduate Research Assistant
Department of Plant Pathology, University of Nebraska-Lincoln
Lincoln, Nebraska, United States
Gazala Ameen, n/a
Assistant Professor
Department of Agronomy, Horticulture and Plant Science, South Dakota State University, Brookings, SD 57007
Brookings, South Dakota, United States
Teddy Garcia-Aroca, PhD
Assistant Professor
Department of Plant Pathology, University of Nebraska-Lincoln
Lincoln, NE, USA
Kyle C. Broderick, n/a
Associate Extension Educator
University of Nebraska-Lincoln
Lincoln, Nebraska, United States
Katherine N. Frels
Assistant Professor
Department of Agronomy and Horticulture, University of Nebraska-Lincoln
Lincoln, Nebraska, United States
Kent M. Eskridge
Professor
Department of Statistics, University of Nebraska-Lincoln
Lincoln, Nebraska, United States
Stephen N. Wegulo
Professor
Department of Plant Pathology University of Nebraska
Lincoln, NE, USA
Bacterial leaf streak (BLS) caused by Xanthomonas translucens pv. undulosa (Xtu) causes significant yield losses in wheat in the Great Plains of the U.S. Previous research has documented yield losses of up to 40% during years with favorable environmental conditions. However, research has not been done to determine yield loss caused by the disease in Nebraska. In this field study, we aimed to evaluate yield loss in winter wheat cv. Wesley by applying five concentrations of Xtu (0.00, 0.06, 0.12, 0.24, and 0.48 optical density (OD)). An experimental unit was a 1.2 m x 4.9 m plot and treatments were arranged in a randomized complete block design with four replications. Two spray inoculations were done at a 7-day interval during the tillering growth stage. Percent disease severity was visually assessed four times starting at four weeks post-inoculation from 24 May to 10 June. At maturity, each plot was harvested using a small plot combine and yield was determined. Disease severity on the final disease assessment date ranged from 3.4% in the 0.00 OD treatment to 43.6% in the 0.48 OD treatment. Yield ranged from 5588 kg/ha in the 0.48 OD treatment to 6936 kg/ha in the 0.00 OD treatment, indicating a 19.4% yield loss. Linear regression analysis showed a strong relationship between yield (dependent variable) and disease severity on the final disease assessment date (R2 = 0.92, P = 0.0105). For each percent increase in disease severity, yield decreased by 36.3 kg/ha. These results indicate that BLS can cause substantial yield loss in winter wheat in Nebraska.