干旱区生态环境知识资源中心

Three isolation techniques, namely soil dilution, soil plating and soil baiting were used to recover six Fusarium species from various soil groups in the arid environment of Bahrain. A total of 428 isolates were recovered using the above techniques. Soil samples analyzed were generally poor in organic matter, slightly alkaline, highly saline and low in total soluble salts. Maximum isolate recovery and species spectrum were mainly recorded from soils of regosols, characterized by low salinity levels (660 mu S cm(-1)). Of species encountered, Fusarium solani, F. equiseti and F. compactum were dominant and frequent in all soil groups. Species prevalence, distribution and total isolate s were greatly influenced by soil salinity, which counteracted other soil parameters. The soil dilution plate yielded the highest population level and species diversity from regosol soils. Significant interaction occurred between the applied technique and species recovery, as determined by chi-square analysis. Results obtained are in favour of the use of multi-isolation techniques and media approach for comparing survey studies of soil-borne Fusarin from noncultivated desert environment.