Occurrence and Diversity of Soil Microflora in Potato Fields of Bangladesh

Microflora from potato rhizosphere soil was isolated from different potato fields of Bangladesh. Seventeen soil samples were analyzed for the presence of microflora in selected potato field soils. Seven fungal species and one bacterium species were morphologically characterized using soil dilution and streak plate methods. The predominant fungi isolated including Alternaria sp., Aspergillus sp., Penicillium sp., Rhizopus sp., Bipolaris sp., Phytophthora sp., Fusarium sp. and one bacterium was identified as Ralstonia solanacearum. Individual colonies of fungi and bacteria were counted on Potato Dextrose Agar (PDA), V8 juice Agar and their presence in soil was compared in respect of different locations of potato fields. The occurrence of Phytophthora sp. was medium in Tongibari and lower in Singair Union, Sonargaon, Matlab Dakshin, Gobindaganj, Palashbari, Gopinathpur and Bagmara. The highest counts of R. solanacearum were found in Singair Union, Tongibari and Daudkandi and the lowest counts were made in Palashbari and Bagmara. This was the first reported examination of the microbial diversity of soil microflora in some selected potato fields of Bangladesh.