Dear DSSAT list,

         My name is Sutisa Pinitpaitoon. I have a problem of DSSATv4.02
underestimating the simulation of maize yield when compare with
observations. I am simulating maize production in Thailand.  I am wondering
if it may be due to DSSAT not including inputs of phosphorus fertilizer.

       I have set the simulation options for the options and outputs tabs in
the Xbuild to be yes for phosphorus.  It seems that this is not including
inputs of phosphorus fertilizer. Firstly, in the summary file of the
simulation there is a zero value for PI#M   (Number of P applications), PICM
   (Inorganic P applied (kg/ha)) and PUPC (P uptake kg/ha). Secondly in the
simulation overview file two treatments with and without triple super
phosphate showed the same yields, both yields are lower than observed
yields.

      My soil has a high P-fixation capacity and P is a limiting nutrient in
this soil. I think P fertilizer has an influence on the higher yields found
in trials.  Can anyone please advise if applications of phosphorus
fertilizer is an option in the model, and if so what I might be doing wrong
which is causing the model to not include this?

       Thank you for your kindness

       Sutisa