Spot Blotch & Net Blotch
Spot blotch, caused by the fungus Cochliobolus sativus, is a common disease of barley in North Dakota, particularly in the warmer and more humid regions of the state. This fungal disease is characterized by small, dark brown to black spots on the leaves, which can coalesce into larger blotches as the infection progresses. The occurrence and severity of spot blotch can be influenced by various factors including cultivar susceptibility, crop rotation practices, and tillage methods. In North Dakota, where barley is a significant crop, the management of spot blotch is of considerable importance. Farmers often rely on an integrated approach, combining the use of resistant varieties, appropriate fungicide application, and cultural practices such as crop rotation and residue management to mitigate the impact of this disease and maintain the quality and yield of their barley crops.
Net form net blotch (NFNB), caused by the fungal pathogen Pyrenophora teres f. teres, is a notable foliar disease affecting barley crops in North Dakota. The disease is recognizable by its signature symptomatology — a 'net-like' pattern of brown to dark necrotic lines crisscrossing the leaves. Conditions in North Dakota, especially when cool and moist, can be conducive to the development and spread of NFNB, putting pressure on barley production. Management of net form net blotch in the region focuses on an integrated approach: utilizing less susceptible barley varieties, implementing crop rotation with non-host crops to break the pathogen cycle, and applying fungicides when necessary. This multifaceted management strategy is vital for preserving grain quality and yield, which are crucial for the profitability of the state's barley producers.