Characterization of Pea Seed-Borne Mosaic Virus, Efficacy of Foliar Applications for Common Bacterial Blight Management in Dry Beans and Impact of Common Bacterial Blight on Prostrate and Upright Beans

PSbMV in field pea has resulted in substantial yield and seed quality losses world-wide and has recently been reported in North Dakota. Traditional management of this virus includes preventative measures such as removal of alternate hosts, planting virus free seed and the use of cultivar resistance. The objectives of this research were to screen field pea cultivars commonly grown in North Dakota for a response to North Dakota PSbMV isolate ND14-1 and ascertain the effect on plant symptoms, seed size and weight, the number of pods and seeds and seed transmission. Two cultivars were identified as highly resistant and one as partially resistant. The results from this study were combined into a risk assessment. Cultivars were categorized based on inherent risk of PSbMV infection, transmission and reduction in total seed weight. Common bacterial blight (CBB) in dry bean is capable of causing substantial yield losses and has been reported in up to 75% of fields in the Northarvest region in the last five years. Current management practices include the use of planting clean seed, crop rotation, partial host resistance and the application of cupric bactericides, although inconsistent for the management of CBB. Growers in this Northarvest region have recently shifted to growing upright (Type II) dry beans rather than prostrate (Type III) dry beans for ease of harvest. The objectives of this research were to evaluate copper products, surface sanitizers and growth promoters for the management of CBB and to discern if Type II dry beans experienced greater yield losses under CBB disease pressure than Type III dry beans. Numerous products were identified that significantly reduced CBB disease severity and spread; however, no significant yield benefit was observed. Across a wide range of disease severity (0-46%), no significant yield losses were observed between high and low disease severity any of the cultivars screened