Bacteria blight is a serious disease on green beans (Phaseolus vulgaris L.) and can affect all the growth and yield parameters of the crop and cause yield loss of about 40 %. Inadequate information exist on the evaluation of nitrogen fertilizer potential on bacterial blight diseases on green beans cultivars. The aim of this study was to access nitrogen fertilizer potential on bacterial blight disease on green beans varieties to improve growth and yield. Three beans varieties (Cora, Dolly and Local black green beans) were planted in the field in a complete randomized block design with twelve treatments and three replicates. Fields were applied with nitrogen fertilizer at different concentrations of 30g and 60g and afterwards treated with rhizobium inoculants except in the control field where no treatment was applied. The data for disease incidence, disease severity, and yield parameters were collected. Pathogenicity assessment was carried out in the green house by inoculating healthy plants with bacterial isolate (2 x 10 4 spores/ml) and the lesion diameter was measured. Significant difference (p ? 0.05) was observed in disease incidence, severity and yield parameters on the different treatments. The highest average number pods per plant of 21 and lowest mean disease severity of 32.6 % was recorded in local black green bean variety treated with rhizobium (bacteria) inoculant. This shows that application of rhizobium inoculant can be used as the best management option to control bacterial blight disease for all the three beans varieties in this study.

Keywords: Bacteria blight disease, nitrogen fertilizer, green beans varieties.