Phenotypic Characterization of Bipolaris oryzae in Fogera Plain, Ethiopia

Rice (Oryzae sativa L.) is one of the most important cereal crops on which an ever-increasing population is dependent for food globally. However, constraints associated with infectious diseases, notably brown spot transmitted by seed and wind reduced its production and productivity. This study was, therefore, conducted with the aim of morphological characterization of Bipolaris oryzae, the causal pathogen of brown spot isolates and screening its resistant Lowland rice pipelines under natural infestation rain-fed conditions in Fogera plains of Amhara region, Ethiopia. Twenty-nine Bipolaris oryzae isolates were collected from Dera, Fogera, and Libokemkem districts and characterized morphologically at the Ambo Agricultural Research Center plant pathology laboratory. These isolates were grouped into nine categories on their colony morphology and growth pattern. Fast, moderate and slow mycelial growth habits were also observed in 29 isolates with varied conidia size and sporulation rates. All tested genotypes and isolates were clustered into four groups and strong correlations were observed between various parameters. However, it is advised to identify inherent resistance genes of the above lines in combination with the pathogen genetic characteristics for fruitful management recommendations.