Hi everyone,

 

My name is Carlos Berná from Cranfield University (UK) and I am doing a research on Climate change impacts on potato crop in UK.

I am using DSSAT v4.0.2. for modelling potato crop growth.

 

I am using field data to feed into the model, and the yields coming out from DSSAT are much lower than those from the field research. I applied the parameters from the field research to use with the model. I got much lower fresh weight yield in both rainfed and irrigated crops (14.13 and 38.92 tones per hectare respectively) comparing to field's results of 42.2 t/ha for irrigated and 104.1 t/ha for irrigated.

 

Irrigation:

I am irrigating on the same dates and applying the same amount as in the field.

Note: I don't think is here the problem since I get also lower yield with rainfed crop.

 

Fertilizer:

160 kg/ha of fertilizer (Nitrogen) applied at once at the beginning of the season.

I tried splitting the dose in more along the season and I get more yield, not much more thought.

I am using ammonium sulfate, could the 'fertilizer material' make a difference in terms of yield result?

 

I am considering that maybe is related to the consistency of the fertilizer to remain in the soil. The Nitrogen plots show that they are very quickly washed out from the soil. In UK the fertilizer is used as granules, which stay in the soil and slowly break down. That's why the fertilizer is applied at the beginning of the season. But maybe the 'fertilizer material' contained in DSSAT are in a liquid form or similar and they stay less time in the soil and therefore the doses have to be split along the season.

 

Do you think I should consider any other parameter to give answer to this problem with low yields?

 

Please feel free to do any comment on this.

 

Kind Regards,

Carlos