INGEBI   02650
INSTITUTO DE INVESTIGACIONES EN INGENIERIA GENETICA Y BIOLOGIA MOLECULAR "DR. HECTOR N TORRES"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
A COMPREHENSIVE APPROACH IN THE SEARCH OF MICROBIAL INDICATORS ASSOCIATED WITH DIFFERENT
Autor/es:
GUERRERO, L.D.; AGARÁS, B.; REYNA, D.; GABBARINI, G.; DUVAL, M.; MARTINEZ, J.M.; FIGUEROLA, E.L.M.; FERRARI, A.; VALVERDE, C.; GALANTINI, J.; ERIJMAN, L.; WALL, L.G.
Lugar:
Seattle, WA, USA
Reunión:
Simposio; The 13th International Symposium on; 2010
Institución organizadora:
International Society of Microbial Ecology
Resumen:
We present the first results of an interdisciplinary project (BIOSPAS) aimed at understanding how the microbial
structure in soil under no-till farming are related to agricultural practices and soil properties. Three treatments were
defined according to land use: 1) Sustainable agricultural management, subjected to intensive crop rotation and
nutrient amendment, 2) Non-sustainable agricultural management with high mono-cropping without nutrient reposition,
3) Natural environment. Blocks of treatments were replicated 4 times in agricultural fields that had documented history
of no-till management, at sites located across a west-east transect in Argentina's Pampas. Each sample was collected in
triplicate, as a composite of 16 soil subsamples from 0-10 cm depth collected at 50 m intervals. The relative abundance
of major taxonomic groups of bacteria was estimated using primer-specific quantitative PCR and PCR-DGGE.
Pseudomonads were evaluated by quantifying the culturable fraction and by molecular markers oprF and gacA. Fatty
acids profile, phosphatase and Glomaline Related Soil Proteins (GRSP) were also surveyed along with key soil variables
(pH, moisture, organic carbon content, total nitrogen and P). Multivariate analysis was used to analyze microbial soil
biology data. Differences in physicochemical and biochemical parameters were more consistently related to agricultural
practices than bacterial community data. Principal component analysis separated soil management independently of
site. Patterns of significant differences between treatments were obtained at the broad level of taxonomic resolution
examined, but for most taxonomic groups the differences were site-specific. The results indicate that no-till systems
support distinctive bacterial community composition and function according to land management, although the
significance of these differences as indicators of soil quality requires further exploration.