Bacterial Pathogens of Wheat: Symptoms, Distribution, Identification, and Taxonomy

Abstract

Bacterial pathogens are significant biotic factors of wheat, a globally important source of carbohydrates. The diseases caused by these pathogens are reported to reduce annual wheat production by about 10% and up to 40% in severe infections occurring early in the growth period. This chapter presents current information on the symptoms, distribution, identification, and taxonomy of key bacterial pathogens of wheat with a focus on the seed-borne bacterium, Xanthomonas translucens pv. undulosa, the causative agent of the leaf streak and black chaff disease. Other wheat- pathogenic bacterial pathogens addressed in the chapter are Pseudomonas syringae pv. syringae, the causal agent of bacterial leaf blight; P. syringae pv. atrofaciens that cause the basal glume rot; Pseudomonas fuscovaginae, the causal agent of the bacterial brown sheath; Erwinia rhapontici, the causal agent of the pink seed of wheat; Pseudomonas cichorii, the causative agent of wheat stem melanosis; Clavibacter tessellarius is respon- sible for the bacterial mosaic of wheat as well as other minor bacterial pathogens. Finally, the chapter proposed the use of genome-based tools for the accurate identifi- cation and classification of bacterial pathogens of wheat.