Dynamics of fungal diversity in different phases of Pinus litter degradation revealed through denaturing gradient gel electrophoresis (DGGE) coupled with morphological examination

Abstract

Fungal diversity in Pinus sylvestris var. mongolica litter was investigated by PCR-DGGE coupled with a traditional cultivation method. Twenty-one fungal strains were isolated by traditional cultivation methodology, most being filamentous fungi. Total DNA was extracted directly from the L, F1, F2 and H litter layers respectively using the bead-beating method. About 460 bp rDNA fragments were obtained by Nested-PCR and analyzed by denaturing gradient gel electrophoresis (DGGE). PCR-DGGE analysis recovered seven operational taxonomic units (OTUs) from the different decomposing litter layers. Six OTUs belonged to Ascomycetes and one to Basidiomycota. Sporobolomyces inositophilus was revealed by both methods, but there was no overlap in other species detected. A major shift of fungal communities on litter occurred during decomposition. The Shannon-Weaver index, which measures diversity in categorical data, was maximal in the F1 layer, then decreased with substratum degradation and reached it lowest value in the H layer. Key words: Fungal diversity, polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE), Traditional culture, Litter.