Vili, please find attached my latest paper where I used Substor-Potato to assess the impact of CC on potato production in England and Wales.
Substor potato has a small bug when used to simulate multiple years with the same parameters, it simulates only the first year. The group who developed Substor has kindly developed for me a small patch to resolve that bug but unfortunately this was not included in the latest version of DSSAT.
Jon, thank you for your initiative I am highly interested in joining the "potato team" and ready to help/share my Substor experience with anyone interested
Best Regards
Andre 
    
Andrè Daccache  MSc  PhD
Research Fellow- Agricultural Water Management
 
Department of Environmental Science and Technology
Cranfield University, Cranfield, Bedfordshire MK43 0AL
Vincent Building (B52 A)
T :+44(0)1234750111 ext 5572
M: +44 (0) 7788988146 
F: +44 (0) 01234 754036
 


-----Original Message-----
From: DSSAT - Crop Models and Applications [mailto:[log in to unmask]] On Behalf Of Jon I. Lizaso
Sent: Monday, October 24, 2011 8:40 AM
To: [log in to unmask]
Subject: Re: need assistance with Substor Potato model evaluation

Dear all,
I believe the potato model has always have fresh weight yield. The original
model description by Griffin, Johnson and Ritchie (1993), shows simulated
results in both fresh and dry weight. I have DSSAT v4.0.2.0 and it does have
fresh weight as well.

Dr. Boote I don't have anything ready yet. I'm currently processing data of
a second year of field data that together with other data sets should lead
to a deep revision and hopefully improvement of the DSSAT potato model.
Anyone interested in joining this effort, please contact me directly
([log in to unmask]).

Best regards,
Jon

Jon I. Lizaso
Universidad Politecnica de Madrid
Dpto. Produccion Vegetal: Fitotecnia
Av. Complutense s/n
28040 Madrid, SPAIN
Tel:  (+34) 91 452 4900 ext 1671
Fax: (+34) 91 544 9983
http://www1.etsia.upm.es/GRUPOSINV/AgSystems/


-----Mensaje original-----
De: DSSAT - Crop Models and Applications [mailto:[log in to unmask]] En
nombre de Boote,Kenneth J
Enviado el: Monday, October 24, 2011 5:38 AM
Para: [log in to unmask]
Asunto: Re: need assistance with Substor Potato model evaluation

All,

The latest potato model will also have a fresh weight prediction ability
(but I don't know if version 4.0 has it).

There will be a potato team to test and compare potato crop models against
data and against each other.  The team will be formed soon.

Meanwhile, those of you who have potato comparison papers with Substor or
other models, please send them to Vili.  John Lizaso, did you have anything
in black and white on this?

Ken Boote
________________________________________
From: Viliamu Iese [[log in to unmask]]
Sent: Sunday, October 23, 2011 9:08 PM
To: Boote,Kenneth J; [log in to unmask]
Subject: need assistance with Substor Potato model evaluation

Bula everyone!

Thank you very much Dr. Boote for the explanation it is very helpful.

Please, we have a student who is interested to evaluate the Substor Potato
model here in Fiji. If you have papers on evaluating the potato model could
you kindly please send them over to assist us with our experimental designs
and collection of data.

Vinaka
Vili


-----Original Message-----
From: DSSAT - Crop Models and Applications [mailto:[log in to unmask]]
On Behalf Of Boote,Kenneth J
Sent: Monday, October 24, 2011 7:39 AM
To: [log in to unmask]
Subject: Re: Multiple Harvesting of Tomato Harvesting

Behnam,

I think you are not comparing this correctly.  Typically the crop model
outputs yield on dry matter basis, and that is what you are getting from
your version of DSSAT.  Your experimental value of 70 ton/ha is fresh
weight.  In the latest version of DSSAT, we have the ability to output fresh
weight of tomato (but that is Version 4.5, which was probably released after
the version that you are using).  So, until you get the latest version, you
cannot make comparison on fresh weight basis.

So, please make your comparison on the base of dry matter yields.  Tomato
fruits are not much more than 6% dry matter concentration, so you would be
off by more than a factor of ten, if you compare model output as dry matter,
to your data as fresh mass.

Multiple harvesting is not the source of your problem.  DSSAT has a "pest"
routine that could mimic partial multiple harvests if you want.  You would
need to create a fraction "pod = tomato" removal on given harvest dates and
enter that in the File T, and also turn on disease (to "Y") via the
simulation controls via XBUILD.  But multiple harvest is not the cause of
your lack of comparability.

Ken Boote

-----Original Message-----
From: DSSAT - Crop Models and Applications [mailto:[log in to unmask]]
On Behalf Of Behnam Ababaei
Sent: Sunday, October 23, 2011 3:55 AM
To: [log in to unmask]
Subject: Multiple Harvesting of Tomato Harvesting

Dear Users,

In the region of my study, tomato is harvested more than 5 times (even 7).
So, the total yield part exceeds even 70 ton/ha. But, in DSSAT, total yields
hardly becomes more than 16 ton/ha. I think this is because DSSAT doesn't
consider the number of harvesting. Am I right? Is there any way to simulate
such a situation (Multiple harvesting)?





Sincerely Yours.

Behnam Ababaei, Ph.D. Candidate,

Department of Irrigation & Reclamation Engineering,

Faculty of Agricultural Engineering & Technology,
College of Agriculture & Natural Resources,

University of Tehran, Karaj, Iran, 31587-77871.

P.O. Box: 4111.