dc.contributor.author | Isaac, Savini | |
dc.contributor.author | Paul, C. Smithson | |
dc.contributor.author | Nancy, K. Karanja | |
dc.contributor.author | Hideo, Yamasaki | |
dc.date.accessioned | 2013-07-25T07:14:24Z | |
dc.date.available | 2013-07-25T07:14:24Z | |
dc.date.issued | 2006 | |
dc.identifier.citation | Savini, I., Smithson, P. C., Karanja, N. K., & Yamasaki, H. (2006). Influence of Tithonia diversifolia and triple superphosphate on dissolution and effectiveness of phosphate rock in acidic soil. Journal of Plant nutrition and soil science, 169(5), 593-604. | en |
dc.identifier.uri | http://onlinelibrary.wiley.com/doi/10.1002/jpln.200521931/pdf | |
dc.identifier.uri | http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/50924 | |
dc.description.abstract | An incubation and a pot experiment were conducted to evaluate the dissolution and agronomic effectiveness of a less reactive phosphate rock, Busumbu soft ore (BPR), in an Oxisol in Kenya. Resin (anion and anion + cation)-extractable P and sequentially extracted P with 0.5 M NaHCO3, 0.1 M NaOH, and 1 M HCl were analyzed. Dissolution was determined from the increase in anion resin (AER)–, NaHCO3-, and NaOH-extractable P in soil amended with PR compared with the control soil. Where P was applied, resin P significantly increased above the no-P treatment. Busumbu-PR solubility was low and did not increase significantly in 16 weeks. Anion + cation (ACER)-extractable P was generally greater than AER-P. The difference was greater for PR than for triple superphosphate (TSP). The ACER extraction may be a better estimate of plant P availability, particularly when poorly soluble P sources are used. Addition of P fertilizers alone or in combination with Tithonia diversifolia (TSP, BPR, TSP + Tithonia, and BPR + Tithonia) increased the concentration of labile inorganic P pools (NaHCO3- and NaOH-Pi). Cumulative evolved CO2 was significantly correlated with cumulative N mineralized from Tithonia (r, 0.51, p < 0.05). Decrease in pH caused NHequation image-N accumulation while NOequation image-N remained low where Tithonia was incorporated at all sampling times. However, when pH was increased, NHequation image-N declined with a corresponding rise in NOequation image-N. Tithonia significantly depressed soil exchangeable acidity relative to control with time. A significant increase (p < 0.05) was observed for P uptake but not dry-mass production in maize where BPR was applied. The variations in yield and P uptake due to source and rates of application were statistically significant. At any given P rate, highest yields were obtained with Tithonia alone. Combination of Busumbu PR with TSP or Tithonia did not enhance the effectiveness of the PR. The poor dissolution and plant P uptake of BPR may be related to the high Fe content in the PR material. | en |
dc.language.iso | en | en |
dc.publisher | University of Nairobi, | en |
dc.subject | Busumbu phosphate rock | en |
dc.subject | Ca;ph | en |
dc.subject | P fractions | en |
dc.subject | resin P | en |
dc.subject | Tithonia | en |
dc.title | Influence of Tithonia diversifolia and triple superphosphate on dissolution and effectiveness of phosphate rock in acidic soil | en |
dc.type | Article | en |
local.publisher | college of agriculture and veterinary services, | en |