Table 1.

List of variables, rates, and parameters used in the model, and their units.

Acronym	Description	Unit
State variables
H	Healthy sites	0 to 1 a
I	Infectious sites, where visible lesions produce conidia	0 to 1
L	Latent sites, where disease symptoms are not visible	0 to 1
R	Removed sites, where visible lesions are old and non-sporulating	0 to 1
V	Visible sites, where lesions are visible, but non-sporulating yet	0 to 1
Rate variables
DISR	Rate of dispersal of conidia	0 to 1
INFR	Rate of infection by conidia	0 to 1
INCR	Rate of incubation	0 to 1
LATR	Rate of latency	0 to 1
REMR	Rate of removal	0 to 1
SPOR’	Rate of conidia production on primary inoculum sources	0 to 1
SPOR”	Rate of conidia production on secondary inoculum sources	0 to 1
Parameters
i	Duration of infectious period in optimum conditions	N hours
IPmin	Minimum length of the incubation period	N hours
k	Abundance of primary inoculum sources	0 to 1
LPmin	Minimum length of the latency period	N hours
p	Duration of latency period in optimum conditions	N hours
r	Apparent infection rate	N
RcOPT	Optimum Rc value	N
Auxillary variables
CON	Abundancy of conidia, i.e., CON = CON’ + CON”	N
CON’	Abundancy of conidia on primary inoculum sources	N
CON”	Abundancy of conidia on secondary inoculum sources	N
HS	Susceptibility of the host plant	0/1 b
IP	Incubation period	N
iP	Infectious period	N
LP	Latency period	N
Computed variables
CF	Correction factor for diseased sites	0 to 1
D	Diseased sites, i.e., D = L + V + I + R	0 to 1
DS	Disease severity	0 to 1
pi	Hourly progress of IP depending on temperature	N
pl	Hourly progress of LP depending on temperature	N
Rc	Basic infection rate corrected for the removal	N
External variables
GS	Growth stage of the plant based on the BBCH scale	–
P	Hourly rainfall	mm
T	Hourly air temperature	°C
Teq	Equivalent of temperature	0 to 1
Tmax	Maximum temperature for sporulation	°C
Tmin	Minimum temperature for sporulation	°C
VPD	Vapor pressure deficit	hPa
WD	Duration of a wet period	N hour
Driving functions
f1(P)	Equation for the effect of rainfall on conidial dispersal and deposition on host tissues	0 to 1
f2(P)	Equation for the effect of rainfall on the wash-off of conidia from host tissues	0 to 1
f(T)	Equation for the effect of temperature on sporulation, or incubation or latency	0 to 1
f(WD)	Equation for the effect of wetness duration on sporulation, or conidial infection
f’(WD)	First derivative of the equation for the effect of wetness duration on sporulation	0 to 1
RcT	Rc modifier for temperature	0 to 1
RcWD	Rc modifier for wetness duration	0 to 1

^a0 to 1 refers to a dimensionless, continuous variable.

^b0/1 refers to a dimensionless, binomial variable (i.e., 0 = the host is not susceptible to infection; 1 = the host is susceptible to infection).