أثر الأسمدة الآزوتية في تراكم النترات في التربة و المياه و ثمار البندورة

الملخص EN

This study aimed to determine the effect of nitrogen fertilizers on nitrate accumulation in soil, water, and fruit tomato in several fields of private farms planted with tomato (lecum) in Mahja site of Daraa province, during the growing season of2010/2011.

Five fields were chosen (W1, W2west, E1, E2 east and West North Mahja) with a surface area of (0.5ha) for every field.

All Fields were irrigated with nearly well water, and fifteen surface soil samples were collected, with three composit samples consisting of three replications for every sample in one field.

Solubility compound fertilizers (20, 20, 20) and urea were added (180 kgN/ha) for W1 field according to the agriculture ministry recommendation, but the other four fields were fertilized with 350kg N/ha.

according to the traditional farming systeme in the area farms.

Soil, well water were described and nitrate content was determined.

Results showed that the nitrate content increased in the soil of studied fields in a comparison to unfarmed soil (with out mineral fertilization), whereas in the WN (North West Mahja) fields the nitrate content reached the highst concentration (32) and (38) mgN-NO3 /kg soil, which amounted to 60% and 90%, in the med and end of season, respectively.

However the lowest nitrate concentration in was in W1field and reached 24 and 28 mgN-NO3 /kg, which increase by 23% and 40% of nitrate concentration in a comparison to its content in soil before faming.

The results also showed no significance difference of nitrate content in well water, and in nitrate concentration during the season.

The nitrate concentration of tomato fruit increased, and the highest was in W2 field at med and end of season (230 and 300) mgN-NO3/kg fruit with additional percentage (39% and 50%) respectively in W1 field (naturally).