Variability on Catellatospora spp. strains isolated from plant materials

Numerous strains of actinomycetes belonging to the "rare" genera were isolated from different plant materials as leaf litters and internal root cortical tissues; among them 53 were identified as members of the genus Catellatospora on the basis of the micromorphology of the reproductive structures. The variability characterizing these strains was studied, in comparison to 5 type strains of the genus, evaluating the cultural features on agar media and the ARDRA profiles obtained by three endonucleases Cfol, HaeIII and HpaII. The different profiles highlight the wide phenotypic and genotypic variability of these strains and the remarkable differences among most of them in comparison to the described ones. Only few strains showed characteristics similar to a type strain, in particular to Catellatospora citrea subsp. citrea, whereas several of them could belong to new taxa. The results achieved were also particularly remarkable under the ecological point of view considering the high number of studied wild isolates, in comparison to the knowledge on these genus based mostly on the descriptions of the few type strains. Furthermore the examined population was strictly connected with plant materials, in particular with leaf litter, instead the type strains were all isolated from woodland soil.