Identification of the polish strains of Chalara ovoidea using RAPD molecular markers

On the basis of morphological features and RAPD markers the strains of Chalara ovoidea found in Poland on planks and on stems of beech trees were identified. As reference strains the cultures taken from CBS Utrecht were employed; they were cultures CBS 354.76 and CBS 136.88. The amplification of genomic DNA was conducted using 10 primers (OPA01-OPA10), 7 of which (OPA01-OPA05, OPA09, OPA10) gave positive results. In total 42 fragment of DNA (bands) were obtained. In case of primers OPA03, OPA04, OPA05, and OPA09 all obtained fragments for analyzed strains were fully monomorphic. This means, that no genetic variability was found using the above mentioned primers. Low genetic variability was ascertained in the analysis of frequency of occurrence of DNA fragments using other primers, namely OPA01, OPA02, and OPA10. The matrix and dendrogram of genetic affinities among different strains of Chalara, calculated using the Jaccard's similarity coefficient suggested, that the most similar strains are the ones coming from Poland (HMIPC 16136 and HMIPC16664) as well as the strain CBS 136.88, while somewhat different from them is the strain CBS 354.76. To determine, how exactly did the dendrogram reflect genetic affinity among analyzed strains, the Mantel's test was employed. The correlation coefficient amounted to 0.78, suggesting that the strains under study had been grouped properly. The results showed, that the fungal strains found in southern Poland represent the species Chalara ovoidea.