title: How changing root system architecture can help tackle a reduction in soil phosphate (P) levels for better plant P acquisition.
abstract: The readily available global rock phosphate (P) reserves may run out within the next 50-130 years, causing soils to have a reduced P concentration which will affect plant P uptake. Using a combination of mathematical modelling and experimental data, we investigated potential plant-based options for optimizing crop P uptake in reduced soil P environments. By varying the P concentration within a well-mixed agricultural soil, for high and low P (35.5-12.5 mg L(-1) respectively using Olsen's P index), we investigated branching distributions within a wheat root system that maximize P uptake. Changing the root branching distribution from linear (evenly spaced branches) to strongly exponential (a greater number of branches at the top of the soil) improves P uptake by 142% for low-P soils when root mass is kept constant between simulations. This causes the roots to emerge earlier and mimics topsoil foraging. Manipulating root branching patterns, to maximize P uptake, is not enough on its own to overcome the drop in soil P from high to low P. Further mechanisms have to be considered to fully understand the impact of P reduction on plant development.
authors.affiliation: Institute for Complex Systems Simulation, University of Southampton, Southampton, SO17 1BJ; Mathematical Sciences, Faculty of Social and Human Sciences, University of Southampton, Southampton, SO17 1BJ; Centre of Operational Research, Management Sciences and Information Systems, University of Southampton, Southampton, SO17 1BJ; IFLS Crop Systems Engineering, University of Southampton, Southampton, SO17 1BJ.
authors.forename: J
authors.initials: J
authors.lastname: Heppell
authors.forename: P
authors.initials: P
authors.lastname: Talboys
authors.forename: S
authors.initials: S
authors.lastname: Payvandi
authors.forename: K C
authors.initials: KC
authors.lastname: Zygalakis
authors.forename: J
authors.initials: J
authors.lastname: Fliege
authors.forename: P J A
authors.initials: PJ
authors.lastname: Withers
authors.forename: D L
authors.initials: DL
authors.lastname: Jones
authors.forename: T
authors.initials: T
authors.lastname: Roose
mesh_terms: D001692:Biological Transport; D008954:Models, Biological; D008962:Models, Theoretical; D010710:Phosphates / Q000378:metabolism*; D018517:Plant Roots / Q000033:anatomy & histology / Q000378:metabolism; D058441:Rhizosphere; D012987:Soil / Q000737:chemistry; D014908:Triticum / Q000033:anatomy & histology / Q000378:metabolism*
chemical_list: D010710:Phosphates; D012987:Soil
keywords: Triticum aestivum; modelling; plant nutrient uptake; rhizosphere; root architecture