Yeast biodiversity in the guts of several pests on maize;: comparison of three methods:: classical isolation, cloning and DGGE

The yeast biodiversity in the guts of several pests (Diabrotica virgifera, Helicoverpa armigera, Ostrinia nubilalis) on maize from two isolation sources was assessed by cultivation-dependent and cultivation-independent methods. These yeasts are considered to bear a potentially high biotechnological relevance due to their potential ability to degrade several mycotoxins incorporated by their hosts. The 97 isolated yeast strains showed 21 different partial sequence types of the 26S rRNA gene which could be assigned to 10 different genera. The determined genera and species are discussed in terms of the meaning of their taxonomic status or their occurrence in nature. Two cultivation-independent methods, cloning and DGGE, were compared. We propose the combination of these methods as well as the combination of both cultivation-independent and cultivation-dependent approaches, for gaining better insights into fungal biodiversity.