Dear Modeller

Happy New Year!
I have been trying to simulate wheat yield by new DSSAT-4 in four
different soils of Japan. The variety is a Japanese cultivar. Actually I
like to see N responses; so I have 4 nitrogen levels (i.e. 0, 80, 160 &
240 kg N/ha application). The data set of 160 N kg/ha treatment of one
soil was used to determine the Genetic Coefficients.

the simulated values for phenology, grain yield, biomass, grain N,
aerial biomass N and straw N were mostly within 20% or near predicted
values in fertilized plots (i.e. 80, 160 & 240 kg N/ha) of three soils.
However, in 0 N plots (no N application), simulated values for grain
yield and biomass is overestimated though the simulated values for
phenology, grain N, aerial biomass N and straw N were mostly within 20%
or near predicted values. Can anyone give some reasons please for
overestimation of grain yield and biomass in 0 N plots.

Thanks in advance.

Anwar



Dr M. R. Anwar
Department of Soils & Fertilizers
National Agricultural Research Center (NARC),
3-1-1 Kannon-dai, Tsukuba,
Ibaraki 305-8666, JAPAN
Telephone: Work: + 81 – 298-388827, Home: + 81 – 298-588007
Fax: + 81 – 298-388837 (work), E-mail: [log in to unmask]