title: Critical tests for determination of microbiological quality and biological activity in commercial vermicompost samples of different origins.
abstract: The aim of the present paper was to show that differences in biological activity among commercially produced vermicompost samples can be found by using a relatively simple test system consisting of microorganism tests on six microbiological media and soilless seedling growth tests with four vegetable crop species. Significant differences in biological properties among analyzed samples were evident both at the level of microbial load as well as plant growth-affecting activity. These differences were mostly manufacturer- and feedstock-associated, but also resulted from storage conditions of vermicompost samples. A mature vermicompost sample that was produced from sewage sludge still contained considerable number of Escherichia coli. Samples from all producers contained several potentially pathogenic fungal species such as Aspergillus fumigatus, Pseudallescheria boidii, Pseudallescheria fimeti, Pseudallescheria minutispora, Scedosporium apiospermum, Scedosporium prolificans, Scopulariopsis brevicaulis, Stachybotrys chartarum, Geotrichum spp., Aphanoascus terreus, and Doratomyces columnaris. In addition, samples from all producers contained plant growth-promoting fungi from the genera Trichoderma and Mortierella. The described system can be useful both for functional studies aiming at understanding of factors affecting quality characteristics of vermicompost preparations and for routine testing of microbiological quality and biological activity of organic waste-derived composts and vermicomposts.
authors.affiliation: Department of Microbiology and Biotechnology, Faculty of Biology, University of Latvia, 4 Kronvalda Blvd, Riga, 1586, Latvia.
authors.forename: Lelde
authors.initials: L
authors.lastname: Grantina-Ievina
authors.forename: Una
authors.initials: U
authors.lastname: Andersone
authors.forename: Dace
authors.initials: D
authors.lastname: Berkolde-Pīre
authors.forename: Vizma
authors.initials: V
authors.lastname: Nikolajeva
authors.forename: Gederts
authors.initials: G
authors.lastname: Ievinsh
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D044822:Biodiversity; D003470:Culture Media / Q000737:chemistry*; D005658:Fungi / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D008828:Microbiological Techniques / Q000379:methods*; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA; D012987:Soil; D012988:Soil Microbiology
chemical_list: D003470:Culture Media; D012987:Soil