Defoliation and below-grouns herbivory in the grass Muhlenbergía quadridentata: effects on plant perfomance and on the root-feeder Phyllophaga sp. (Coleoptera, Melolonthidae)
Por: Morón Ríos, Alejandro. Doctor [autor/a].
Dirzo, Rodolfo [autor].
Tipo de material: Artículo en línea Tipo de contenido: Texto Tipo de medio: Computadora Tipo de portador: Recurso en líneaTema(s): Muhlenbergia quadridentata | Pastos | Phyllophaga | Defoliación | HerbívorosTema(s) en inglés: Muhlenbergía quadridentata | Grasses | Phyllophaga | Defoliation | HerbivoresClasificación: AR/584.9 / M6 Nota de acceso: Disponible para usuarios de ECOSUR con su clave de acceso En: Oecología. Volumen 110, número 2 (April 1997). páginas 237-242. --ISSN: 0029-8549Número de sistema: 54350Resumen:Tipo de ítem | Biblioteca actual | Colección | Signatura | Estado | Fecha de vencimiento | Código de barras |
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Artículos | Biblioteca Electrónica Recursos en línea (RE) | ECOSUR | Recurso digital | ECO400543509522 |
Disponible para usuarios de ECOSUR con su clave de acceso
In this study we evaluated (1) the combined effects of simulated defoliation and below-ground herbivory (BGH) on the biomass and nitrogen content of tillers and roots of the bunchgrass Muhlenbergia quadridentata and (2) the effect of defoliation on the survival of third-instar root-feeder larvae of Phyllophaga sp. The experiment was performed in a pine forest area at an altitude of 3200 m above sea level. The grass and the root-feeder species were native and dominant in the understory and in the macroarthropod root-feeder communities, respectively. Plants were established in pots in the field and were subjected to the following treatments in a factorial design: simulated defoliation (three levels) and BGH (with or without root-feeder larvae) with ten replicates per treatment. Plants were defoliated three times at 2-month intervals. The interaction between defoliation and root herbivory was significant for all components of plant biomass. In every case, light defoliation with BGH decreased live above-ground, root and total plant biomass, and the number of live tillers by more than 50% with respect to the same defoliation level without root-feeders. Plants apparently did not compensate for the carbon drain by root-feeders when a high proportion of older leaves were not removed by defoliation. Plants under heavy defoliation were not affected by the presence of root-feeders and showed a greater live/dead above-ground biomass ratio than lightly defoliated and control plants. Defoliation and BGH did not change tiller and root N concentrations but root herbivores did decrease live-tiller N content in lightly defoliated plants. Root-feeders but not defoliation decreased the root/shoot ratio by 40% and the live/dead above-ground biomass ratio by 45% through increased tiller mortality. Survivorship and final biomass of Phyllophaga sp. larvae were not affected by defoliation treatments during the 6-month study period. eng