Table 1.

Name, symbol, definition, nominal value, and unit of the 75 parameters of the wheat simulation model SiriusQuality2

All of the parameters belong to eight submodels of Phenology, Leaf layer expansion, Light interception and use efficiency, Grain, DM allocation, N allocation, Root growth and N uptake, and Soil drought factors.

Name	Symbol	Definition	Nominal value	Unit
Phenology
Dse	D se	Thermal time from sowing to emergence	150	°Cd
MaxL	$L_{\text{max}}^{\text{abs}}$	Absolute maximum leaf number	18	Leaf
MinL	$L_{\text{min}}^{\text{abs}}$	Absolute minimum possible leaf number	8.7	Leaf
MaxLeafSoil	$L_{\text{max}}^{\text{soil}}$	Leaf number up to which the canopy temperature is equal to the soil temperature	4	Leaf
Lincr	$L_{\text{incr}}^{}$	Leaf number above which P is increased by Pincr	8	Leaf
Ldecr	$L_{decr}^{}$	Leaf number up to which P is decreased by Pdecr	2	Leaf
P	P	Phyllochron	100	°Cday
Pdecr	P decr	Factor decreasing the phyllochron for leaf number less than Ldecr	0.75	Dimensionless
Pincr	P incr	Factor increasing the phyllochron for leaf number higher than Lincr	1.25	Dimensionless
SLDL	SLDL	Daylength response of leaf production	0.15	Leaf h–1 (daylength)
PFLLAnth	$t_{\text{flag}}^{\text{anth}}$	Phyllochronic duration of the period between flag leaf ligule appearance and anthesis	3	Dimensionless
IntTvern	$T_{\text{int}}^{\text{ver}}$	Intermediate temperature for vernalization to occur	8	°C
MaxTvern	$T_{\text{max}}^{\text{ver}}$	Maximum temperature for vernalization to occur	17	°C
VAI	VAI	Response of vernalization rate to temperature	0.001	d–1 °C–1
VBEE	VBEE	Vernalization rate at 0°C	0.009	d–1
Leaf layer expansion
AreaPL	$A_{{\text{L}}_{\text{N-1}}}^{\text{pot}}$	Maximum potential surface area of the penultimate leaf lamina	31	cm2 lamina–1
AreaSL	$A_{{\text{L}}_S}^{\text{pot}}$	Potential surface area of the leaves produced before floral initiation	2.56	cm2 lamina–1
AreaSS	$A_{{\text{S}}_S}^{\text{pot}}$	Potential surface area of the sheath of the leaves produced before floral initiation	1.83	cm2 sheath–1
PexpL	$t_{}^{\text{exp}}$	Phyllochronic duration of leaf lamina expansion	1.1	Dimensionless
PlagLL	$t_{{\text{L}}_{\text{N-1}}}^{\text{lag}}$	Potential phyllochronic duration between end of expansion and beginning of senescence for the leaves produced after floral initiation	6	Dimensionless
PlagSL	$t_{{\text{L}}_S}^{\text{lag}}$	Potential phyllochronic duration between end of expansion and beginning of senescence for the leaves produced before floral initiation	1.7	Dimensionless
PsenLL	$t_{{\text{L}}_{\text{N-1}}}^{\text{sen}}$	Potential phyllochronic duration of the senescence period for the leaves produced after floral initiation	9	Dimensionless
PsenSL	$t_{{\text{L}}_S}^{\text{sen}}$	Potential phyllochronic duration of the senescence period for the leaves produced before floral initiation	3.3	Dimensionless
RatioFLPL	${\alpha }_{{\text{L}}_N{\text{/L}}_{\text{N-1}}}^{}$	Ratio of flag leaf to penultimate leaf lamina surface area	1	Dimensionless
aSheath	${\alpha }_{\text{sheath}}$	Constant of the quadratic function relating the surface area of leaf sheath between two successive ligules and leaf rank after floral initiation	1.09	Dimensionless
NLL	η	Number of leaves produced after floral initiation	4.5	Leaf
Light interception and use efficiency
Kl	K L	Light extinction coefficient	0.4	m2 (ground) m–2 (leaf)
FacCO2	$k_{{\text{CO}}_{\text{2}}}^{}$	Sensitivity of RUE to air CO2 concentration	0.3	Dimensionless
TauSLN	k N	Relative rate of increase of RUE with specific leaf N	1.9	m2 (leaf) g–1 (N)
SlopeFR	k R	Slope of the relationship between RUE and the ratio of diffuse to total solar radiation	1.5	Dimensionless
RUE	RUE	Potential radiation use efficiency under overcast conditions	3.4	g (DM) MJ–1
Tmax	$T_{\text{max}}^{\text{RUE}}$	Temperature at which RUE is null	50	°C
Topt	$T_{\text{opt}}^{\text{RUE}}$	Optimal temperature for RUE	18	°C
Grain
Dcd	D cd	Duration of the endosperm cell division phase	250	°Cd
Der	D er	Duration of the endosperm endoreduplication phase	450	°Cd
Dgf	D gf	Grain filling duration (from anthesis to physiological maturity)	750	°Cd
Kcd	k cd	Relative rate of accumulation of grain structural DM	0.0084	(°Cd)–1
AlphaNC	αN/C	Grain structural N to C ratio	0.02	Dimensionless
EarGR	σ	Ratio of grain number to ear dry matter at anthesis	100	Grain g–1 (DM)
DM allocation
Deg	D eg	Fraction of PFLLAnth for ear growth before anthesis (counted from flag leaf ligule appearance)	0.25	Dimensionless
SLWp	SLWp	Potential specific lamina DM	45	g (DM) m–2
SSWp	SSWp	Potential specific sheath DM	90	g (DM) m–2
FracLaminaBGR	γlaminae	Fraction of anthesis laminae DM allocated to the grain	0.25	Dimensionless
FracSheathBGR	γsheath	Fraction of anthesis sheath DM allocated to the grain	0.25	Dimensionless
FracStemWSC	γwsc	Fraction of anthesis stem DM in the water-soluble carbohydrate pool	0.1	Dimensionless
FracBEAR	μ	Fraction of biomass allocated to the ear during the ear growth period	0.5	Dimensionless
N allocation
LLOSS	LLOSS	Fraction of leaf N resorption resulting in a reduction of LAI	0.6	m2 (leaf) m–2 (ground)
CritSLN	$N_{\text{cri}}^{\text{LA}}$	Critical area-based N content for leaf expansion	1.5	g (N) m–2 (leaf)
MaxSLN	$N_{\text{max}}^{\text{LA}}$	Maximum potential specific leaf N of the top leaf layer	2.2	g (N) m–2 (leaf)
MinSLN	$N_{\text{min}}^{\text{LA}}$	Specific leaf N at which RUE is null	0.35	g (N) m–2 (leaf)
StrucLeafN	$N_{\text{stru}}^{\text{LM}}$	Structural N concentration of the leaves	0.006	g (N) g –1 (DM)
MaxStemN	$N_{\text{max}}^{\text{SM}}$	Maximum potential stem N concentration	0.0075	m (N) g–1 (DM)
StrucStemN	$N_{\text{stru}}^{\text{SM}}$	Structural N concentration of the true stem	0.005	g (N) g –1 (DM)
AlphaKn	${\alpha }_{K_{\text{N}}}^{}$	Scaling coefficient of the relationship between the ratio of N to light extinction coefficients and the N nutrition index	3.82	m2 (ground) m–2 (leaf)
AlphaSSN	${\alpha }_{N_{\text{LA}}/N_{\text{ShA}}^{}}^{}$	Scaling coefficient of the allometric relationship between area-based lamina and sheath N mass	0.9	g (N) m–2
AlphaNNI	${\alpha }_{\text{NNI}}^{}$	Scaling coefficient of the N dilution curve	5.35	102 × g (N) g–1 (DM)
BetaKn	${\beta }_{K_{\text{N}}}^{}$	Scaling exponent of the relationship between the ratio of N to light extinction coefficients and the N nutrition index	2.063	Dimensionless
BetaSSN	${\beta }_{N_{\text{LA}}/N_{\text{ShA}}^{}}^{}$	Scaling exponent of the relationship between area-based lamina and sheath N mass	1.37	Dimensionless
BetaNNI	${\beta }_{\text{NNI}}^{}$	Scaling exponent of the N dilution curve	0.442	Dimensionless
MaxLeafRRND	${\chi }_{\text{leaf}}$	Maximum relative rate of leaf N depletion	0.004	(°Cd)–1
MaxStemRRND	${\chi }_{\text{stem}}$	Maximum relative rate of stem N depletion	0.004	(°Cd)–1
Root growth and N uptake
DMmaxNuptake	$C_{\max }^{\text{Nuptake}}$	Crop DM at which the potential rate of root N uptake equals MaxNuptake	100	g (DM) m–2
MaxRWU	K max	Maximum relative rate of root water uptake from the top soil layer	0.1	d–1
MaxNuptake	$N_{\text{pot}}^{\text{uptake}}$	Maximum potential rate of root N uptake	0.5	g (N) m–2 (ground) d–1
RVER	RVER	Rate of root vertical extension	0.001	m (°Cd)–1
BetaRWU	λ	Efficiency of the root system to extract water through the vertical soil profile	0.07	Dimensionless
Soil drought factors
MaxDSF	DSFmax	Maximum rate of acceleration of leaf senescence in response to soil water deficit	3.25	Dimensionless
LowerFTSWexp	$W_{\text{lower}}^{\text{exp}}$	Fraction of transpirable soil water for which the rate of leaf expansion equals zero	0.25	Dimensionless
LowerFTSWgs	$W_{\text{lower}}^{\text{gs}}$	Fraction of transpirable soil water for which the stomatal conductance equals zero	0.1	Dimensionless
LowerFTSWrue	$W_{\text{lower}}^{\text{RUE}}$	Fraction of transpirable soil water for which RUE equals zero	0	Dimensionless
LowerFTSWsen	$W_{\text{lower}}^{\text{sen}}$	Fraction of transpirable soil water value for which DSFmax is reached	0.1	Dimensionless
UpperFTSWexp	$W_{\text{upper}}^{\text{exp}}$	Fraction of transpirable soil water threshold for which the rate of leaf expansion starts to decrease	0.65	Dimensionless
UpperFTSWgs	$W_{\text{upper}}^{\text{gs}}$	Fraction of transpirable soil water threshold for which the stomatal conductance starts to decrease	0.5	Dimensionless
UpperFTSWrue	$W_{\text{upper}}^{\text{RUE}}$	Fraction of transpirable soil water threshold for which RUE starts to decrease	0.3	Dimensionless
UpperFTSWsen	$W_{\text{upper}}^{\text{sen}}$	Fraction of transpirable soil water threshold for which the rate of leaf senescence starts to accelerate	0.5	Dimensionless