Strategies for establishing adequate phosphorus levels in three soils with different phosphorus fixing capacities
| dc.contributor.author | Eliuth, Stephan Ngailo | |
| dc.date.accessioned | 2025-02-18T10:06:55Z | |
| dc.date.available | 2025-02-18T10:06:55Z | |
| dc.date.issued | 2004 | |
| dc.description | Dissertation | |
| dc.description.abstract | A study was conducted under pot and field conditions to establish adequate levels of phosphorus in three soils with different P fixing capacities. These soils were from Magadu, Morogoro District, classified as Oxic Haplustidt, Sasanda, in Mbozi District, classified as Drystropept and Nkundi in Nkasi District, classified as Acruoxic Kancliustult. A pot experiment was conducted at SUA- Department of Soil Science while field experiment was carried out at Sasanda in Mbozi District in Mbeya region. The treatments were 0, 40, 80 and 160 mg P/kg of soil for Nkundi, 0, 100, 200 and 400 mg P/kg of soil for Magadu and 0, 800, 1600 and 3200 mg P/kg of soil for Sasanda soil. For field experiment the treatments were 0, 800, 1600 and 3200 kg P/ha. The sources of P were TSP and MPR. There were seven treatments for field and eight treatments for pot experiment. The experiment was laid out in a Randomized Complete Block Design. The tested crop was maize {Zea mays var UH 615). The objectives of the study were to identify rates of P required for optimizing maize dry matter grain yields, and associated available P levels in the soils. Results of the study showed that, both TSP and MPR were effective sources of P in the soils studied. Both TSP and MPR significantly (P = 0.05) increased DM and grain yield, P uptake and available P over the control by 97.7, 95.8, 76,8 and 95.3%, respectively in Sasanda soil. This was attributed to 95.3% increase in available P in the soil after TSP and MPR application in Sasanda soil. This was supported by the highest grain yield, DM yield, and P uptake of 2.97 t/ha, 64.18 g, and 124.8 mg/kg at the rates of 3200 kg P/ha and 3200 mg/kg, respectively in Sasanda soil. However, MPR was slightly less effective than TSP for most of the aspects studied. The optimum rates were 160, 200 and 3200 mg P/kg for Nkundi, Magadu and Sasanda soils, respectively under pots. However, these rates have to be confirmed under field conditions. In Sasanda field experiment, P application did not significantly (P = 0.05) increase available P and the available P was below the critical level. This was attributed to high fixing capacity of the soil. The rale of 1600 kg P/ha gave the highest grain yield of 2.97 t/ha in the current study. Results from the current study indicated that MPR has the potential of supplying P for maize production therefore it could be used as an alternative source of P to TSP. A large, one-time application of P on highly P deficient soils is not always the solution for correcting P deficiency in all soils like in Sasanda soil. A gradual seasonal P application might be the most cost-effective approach for high P-fixing soils. | |
| dc.description.sponsorship | DANIDA | |
| dc.identifier.uri | https://www.suaire.sua.ac.tz/handle/123456789/6563 | |
| dc.language.iso | en | |
| dc.publisher | Sokoine University of Agriculture | |
| dc.subject | Sasanda- Mbozi district | |
| dc.subject | Soils | |
| dc.subject | Soil science | |
| dc.title | Strategies for establishing adequate phosphorus levels in three soils with different phosphorus fixing capacities | |
| dc.type | Thesis |