A calorimetric study of the interaction between Brachiaria platyphylla and soil microbial activity

Authors
Schabes, Fanny Isabel; Sesto Cabral, María Eugenia; Sigstad, Emma Elizabeth
Publication Year
2011
Language
English
Format
article
Status
Published version
Description
Recently, lemon tree plantations in Tucumán province, Argentina were invaded with the weed Brachiaria platyphylla (broadleaf signalgrass). In order to understand the mechanisms involved with its propagation, soils collected from the invaded (IS), not yet invaded (NIS) and from an adjacent forest soil (FS) were comparatively studied by chemical and calorimetric techniques. Also the ethyl acetate (EtOAc) extract of aerial parts and roots as well as the methanol (MeOH) extract of aerial parts were studied in their interaction with soil. Two probable factors involved with B. platyphylla invasibility were found. The first deals with the quality of the IS that resembled more the indigenous FS than the NIS. The microbial quotient (Cmic/Corg) was higher for IS than for NIS. Also, the calorespirometric quotient (p/rCO2) was lower for the former soil indicating a greater microbial mineralizing activity. The second factor deals with the effect of the organic extracts on soil. The EtOAc extract of aerial parts of B. platyphylla showed antimicrobial and allelopathic effects that could be attributed to its phenolic content. However, the MeOH extract of aerial parts and EtOAc extract of roots seemed to induce the activity of phenol degrading bacteria. Therefore, the phenolic content of this species would not be a problem for itself although they seem to act as allelochemicals for native species.
Fil: Schabes, Fanny Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina
Fil: Sesto Cabral, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina
Fil: Sigstad, Emma Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina
Subject
BRACHIARIA PLATYPHYLLA
CALORIMETRY
INVASIVENESS
SOIL MICROBIAL ACTIVITY
Meteorología y Ciencias Atmosféricas
Ciencias de la Tierra y relacionadas con el Medio Ambiente
CIENCIAS NATURALES Y EXACTAS
Access level
Restricted access
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/52467