title: Microbial enhancement of compost extracts based on cattle rumen content compost - characterisation of a system.
abstract: Microbially enhanced compost extracts ('compost tea') are being used in commercial agriculture as a source of nutrients and for their perceived benefit to soil microbiology, including plant disease suppression. Rumen content material is a waste of cattle abattoirs, which can be value-added by conversion to compost and 'compost tea'. A system for compost extraction and microbial enhancement was characterised. Molasses amendment increased bacterial count 10-fold, while amendment based on molasses and 'fish and kelp hydrolysate' increased fungal count 10-fold. Compost extract incubated at 1:10 (w/v) dilution showed the highest microbial load, activity and humic/fulvic acid content compared to other dilutions. Aeration increased the extraction efficiency of soluble metabolites, and microbial growth rate, as did extraction of compost without the use of a constraining bag. A protocol of 1:10 dilution and aerated incubation with kelp and molasses amendments is recommended to optimise microbial load and fungal-to-bacterial ratio for this inoculum source.
authors.affiliation: Centre for Plant and Water Science (CPWS), Faculty of Science, Engineering & Health, CQUniversity, Rockhampton, 4702 QLD, Australia. k.shrestha@cqu.edu.au
authors.forename: Karuna
authors.initials: K
authors.lastname: Shrestha
authors.forename: Pramod
authors.initials: P
authors.lastname: Shrestha
authors.forename: Kerry B
authors.initials: KB
authors.lastname: Walsh
authors.forename: Keith M
authors.initials: KM
authors.lastname: Harrower
authors.forename: David J
authors.initials: DJ
authors.lastname: Midmore
mesh_terms: D000818:Animals; D002417:Cattle; D012417:Rumen / Q000382:microbiology*; D012987:Soil; D012988:Soil Microbiology
chemical_list: D012987:Soil