Abstract

Investigations into occurrence of fungus Aphanomyces frigidophilus in water of springs Dojlidy Górne, Jaroszówka and Pietrasze within the town BiaÅ‚ystok in Podlasie Province, Poland were conducted in Winter, Spring, Summer and Autumn of the year 2005. Samples were processed in the laboratory by routine methods commonly used to isolate these organisms. Bait method with the use of hemp seeds Cannabis sativa, small pieces of snake skin Natrix natrix and exuviae of shrimp Gammarus sp. as bait was applied to isolate the fungus Aphanomyces frigidophilus from the springs. The isolate was maintained on Potato Dextrose Agar PDA and stored in the culture collection of the Real Jardín Botánico CSIC Madrid, Spain. Aphanomyces frigidophilus occurred in 18 [(6)16.7%) in Winter, 3(8.3%) in Spring, 2(5.6%) in Summer, 7(19.4%) in Autumn, 2005] of the examined water samples. In Spring Dojlidy Górne it was very common and was found in all research seasons. The isolate was characterized by studding sequencing the internal transcribed spacer of nuclear DNA (ITS1+5.8S+ITS2). The results indicated the sequence comparisons of two ITS nuclear DNA for species identification: Aphanomyces frigidophilus 18S ribosomal RNA gene, partial sequence, internal transcribed spacer 1, 5.8S ribosomal RNA gene, and internal transcribed spacer 2, complete sequence and 28S ribosomal RNA gene, partial sequence. The results indicated the sequence of our isolate corresponded to the species Aphanomyces frigidophilus (AY647192, version AY647192.1; GI: 48766837).

Key words: Aphanomyces frigidophilus, snake skin of Natrix natrix and exuviae of shrimp Gammarus sp.

Abbreviation

Abbreviations: PDA, Potato Dextrose Agar; ITS, internal transcribed spacer; PCR, polymerase chain reaction; NCBI, National Centre of Biotechnology Information.