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Necesidad de energía para la fijación simbiótica de nitrógeno
1Department of Agronomy, Waite Agricultural Research Institute, University of Adelaide, Glen Osmond, South Australia.
Nature
|May 12, 1977
Resumen
Legumbres Legumbres Las legumbres son legumbres que se encuentran en el suelo.
Área de la Ciencia:
- Fisiología vegetal Fisiología vegetal
- La bioquímica es la bioquímica.
- Ciencias agrícolas Ciencias agrícolas.
Sus antecedentes:
- El nitrógeno es esencial para el crecimiento de las plantas.
- Las legumbres pueden fijar el nitrógeno atmosférico simbióticamente.
- El nitrógeno también se puede asimilar a partir de nitratos del suelo.
Objetivo del estudio:
- Para comparar los costos energéticos de la fijación simbiótica de nitrógeno frente a la asimilación de nitratos en las legumbres.
- Para probar la hipótesis de que la fijación simbiótica de nitrógeno y la asimilación de nitratos tienen costos de energía similares.
Principales métodos:
- Utilizó un método McCree modificado.
- Se investigó el eflujo de CO2 en Trifolium subterraneum L. (trevo subterráneo).
- Dividió el eflujo de CO2 oscuro en componentes de síntesis y mantenimiento.
Principales resultados:
- La fijación simbiótica de nitrógeno y la asimilación de nitratos requieren energía comparable.
- Aproximadamente el 15% de la producción fotosintética neta se asigna a las necesidades de nitrógeno.
- La fijación y asimilación de nitrógeno contribuyen al flujo de CO2 asociado con la síntesis.
Conclusiones:
- El costo energético de la fijación simbiótica de nitrógeno es similar al de la asimilación de nitratos.
- Las legumbres que utilizan la fijación simbiótica del nitrógeno exhiben coeficientes de crecimiento similares a los que utilizan el nitrógeno mineral.
- Esto apoya la hipótesis de costos de energía equivalentes para diferentes estrategias de adquisición de nitrógeno.
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