آزاد سازي فسفر قابل استفاده با كاربرد كودهاي آلي شيميايي و جذب آن توسط گندم در خاكهاي آهكي

Phosphorus release and uptake in wheat using organic and chemical fertilizers on calcareous soils

This study was conducted to evaluate the release of Phosphorus available by application of organic and chemical fertilizers in three soils with different values available phosphorus: very low (S1)، low (S2) and medium (S3)، in each soil applied 50 mg of phosphorus per kg of soil from sheep manure، municipal solid waste compost and triple super phosphate. The amounts of phosphorus were measured at the time of 1، 3، 7، 14، 28، 40، 60 and 90 days. The results showed that the impact of the application of phosphorus fertilizer source was different on changes in available phosphorus in the S1 during the incubation period. Even though phosphorus availability with the use of triple super phosphate was higher than municipal waste compost and sheep manure، but these differences are significantly reduced over time. In S1، differences in phosphorus concentrations with the use of triple super phosphate and sheep manure at the beginning of the period was 11.01 and the end of incubation was 0.50 mg kg-1. These amounts with the use of municipal waste compost were 15.87 and 1.30 mg kg-1. In S2، sheep manure was able to released available phosphorus at the end of incubation and was a suitable substitute for chemical fertilizer to supply phosphorus for the soil. Phosphorus released from triple super phosphate fertilizer was 12.88 mg kg-1 of period time. With the use of sheep manure، was 12.70 mg kg-1 of incubation. Phosphorus released in S3 with triple super phosphate was 25.51mg kg-1 at the beginning of period and 19.08 mg kg-1 at the end of the incubation time. These values for sheep manure were 17.45 and 11.63 mg kg-1 and municipal waste compost 8.24 and 8.86 mg kg-1 respectively. In the greenhouse phase، plant total phosphorus concentration was larger amount than other treatments in S2. So that the ratio to treatment with sheep manure، 28.7% of municipal solid waste compost، 15.7% and compared to the control، increased 21.2%.