An updated model for nitrate uptake modelling in plants. II. Assessment of active root involvement in nitrate uptake based on integrated root system age: measured versus modelled outputsReport as inadecuate




An updated model for nitrate uptake modelling in plants. II. Assessment of active root involvement in nitrate uptake based on integrated root system age: measured versus modelled outputs - Download this document for free, or read online. Document in PDF available to download.

1 PIAF - Laboratoire de Physique et Physiologie Intégratives de l-Arbre Fruitier et Forestier 2 EVA - Ecophysiologie Végétale, Agronomie et Nutritions

Abstract : An updated version of a mechanistic structural-functional model was developed to predict nitrogen N uptake throughout the growth cycle by a crop of winter oilseed rape, Brassica napus, grown under field conditions. The functional component of the model derives from a revisited conceptual framework that combines the thermodynamic Flow-Force interpretation of nitrate uptake isotherms and environmental and in planta effects on nitrate influx. Estimation of the root biomass structural component is based upon a combination of root mapping along the soil depth profile in the field and a relationship between the specific root length and external nitrate concentration. The root biomass contributing actively to N uptake was determined by introduction of an integrated root system age that allows assignment of a root absorption capacity at a specific age of the root. Simulations were well matched to measured data of N taken up under field conditions for three levels of N fertilization. The model outputs indicated that the two topsoil layers 0-30 and 30-60 cm contained 75-88 % of the total root length and biomass, and accounted for 90-95 % of N taken up at harvest. This conceptual framework provides a model of nitrate uptake that is able to respond to external nitrate fluctuations at both functional and structural levels.

Keywords : Nitrate N uptake regulation Flow-Force interpretation nitrogen uptake efficiency root development root longevity functional-structural plant model N uptake modelling Brassica napus winter oilseed rape temporal growth-patterns brassica-napus l nutrient-uptake no3-uptake electrokinetic interpretation arabidopsis-thaliana biological systems diurnal regulation





Author: Philippe Malagoli - Erwan Le Deunff -

Source: https://hal.archives-ouvertes.fr/



DOWNLOAD PDF




Related documents