INQUINOA   21218
INSTITUTO DE QUIMICA DEL NOROESTE
Unidad Ejecutora - UE
artículos
Título:
Interaction between Brachiaria platyphylla and soil microbial activity. Chemical and calorimetric analysis
Autor/es:
SESTO CABRAL M. EUGENIA; SIGSTAD E.E.
Revista:
BIOCHEMICAL SYSTEMATICS AND ECOLOGY
Editorial:
PERGAMON-ELSEVIER SCIENCE LTD
Referencias:
Año: 2010
ISSN:
0305-1978
Resumen:
Abstract Recently, lemon tree plantations in Tucumán province, Argentina were invaded with the weed Brachiaria platyphylla. In order to understand the mechanisms involved with its propagation, soils collected from the invaded area (IS), not yet invaded (NIS) and from an adjacent forest soil (FS) were comparatively studied by chemical and calorimetric techniques. Also the EtOAc extracts of aerial parts and roots as well as the MeOH extract of aerial parts were studied in their interaction with soil. Two probable factors involved with B. platyphylla invasibility were found. The first had 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 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 phenols 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.