Assessment of Indigenous Rhizobia in faba bean (Vicia faba l.) Soils of Kersa Malima District Southwest Shoa Zone of Oromia, Ethiopia

Abstract

Estimation of the indigenous rhizobia population plays a great role to determine the abundance of rhizobia in the soil and for the need of inoculation. This research paper aimed to assess the population of rhizobia nodulating faba bean in relation to cropping history and soil properties in fababean producing areas of Kersa Malima Districts. Fifteen composite soil samples were collected at the depth of 0-20cm from district`s and the most probable number was used to count rhizobia and plant infection method. The soil rhizobia population was ranged from 0.357*102-9.324*103 cells/g of dry soil. Farm fields with history of legumes cultivation had the highest rhizobia population abundance than cereal-cereal-rotation. Soil pH, organic carbon and available phosphorus influenced soil rhizobia abundance. The study revealed that the land slope influence was not observed at all sites on soil rhizobia population size. Therefore, the present study showed variation in indigenous rhizobia population was observed from soils of Kersa Malima district.