Isolation and Selection of Indigenous Bacterial Strains with Suppression Properties from the Rhizospheres of Potato and Wheat

Soil-borne fungal and bacterial root pathogens can cause serious losses to agricultural crops. The enhancement of disease suppressive properties of soils will limit disease development, thus, being of great importance for sustainable agriculture as well as organic farming systems. The aim of the present study is to isolate, identify and to select indigenous bacterial strains with antifungal activity from the potato and wheat rhizospheres. 111 bacterial strains were obtained in the preliminary screening, from the antagonism test plates, 50 from potato and 61 from wheat. About 55% were Gram+ and about 46% were Gram-. Fourteen bacterial strains from potato revealed an antagonistic activity in vitro against the phytopathogenic fungi, Phytophthora infestans, Fusarium oxysporum f. sp. albedinis and Fusarium solani var. coeruleum with a percentage of inhibition varying from 0 to 92.30%. Twenty four bacterial strains from wheat had an antagonistic activity in vitro against the studied fungi with a range from 0 to 87%. This shows a promising beginning for detecting suppressive soils in Sétif aria.