Hi Mohammad,
 
You are right, the phenology codes which are used in CERES for wheat rather
physiological stages.
 
If the genetic coefficients are fitted to your data (i.e. to the cultivars
you are using) you shouldn't have any problems when comparing recorded with
simulated LAI for the same calendar date. Simulated LAI are stored in the
output file OUT2.WH. CERES allows you to change the output frequency of this
file.
 
In CERES-Wheat the genetic coefficients P1V and P1D control development
until terminal spikelet (TS). PHINT (Phylocron) controls development from TS
to the  beginning of grain filling. The period between TS and the beginning
of ear growth lasts 3*PHINT, and the period between beginning of ear growth
until the end of ear growth lasts 2*PHINT. CERES asumes 80 degree days from
then on until anthesis.
 
I work in crop physiology of wheat in Balcarce, Argentina. We fitted the
genetic coefficients with data from our experiments by trial and error,
modifying them until recorded and simulated values were paired. In order to
adjust P1V and P1D, records of TS date would be useful. In Argentina, double
riedge is paired with Zadok's stage 14 and TS with 31. If you do not have TS
records, P1V, P1D and PHINT can be adjusted by means of date of anthesis: in
order to adjust the 3 coefficients unequivocally, at least 3 records of
anthesis date are needed.
 
Pablo Abbate
Unidad Integrada Balcarce
Buenos Aires, Argentina
 
 
>Dear DSSAT Folks
>The phenology codes which are used in DSSAT3 for wheat
>are rather physiological stages which usually are not one
>observe and record in the field. The codes used in the model
>is:
>Terminal Spikelet
>End of vegetative growth
>End of ear growth
>End of ear growth
>Beg. of grain filling
>Maturity
>now my problem is that our recorded phenolgy data are in
>Zadoks scale, so when I want to compare for example LAI
>at a recorded time with simulated one I cannot track the
>identical time in the simulated time.
>Is there any suggestion regarding this ?
>Thanks
>Mohammad Bannayan
>PhD student
>Nottingham University
>UK
>
>