The Effect Of Tithonia Diversifolia (Hemsley) A. Gray Biomass On The Solubility Of Rock Phosphates: A Laboratory Incubation Experiment. Tropical And Subtropical Agro Ecosystems.
Date
2004Author
Karanja, NK
Gachene, CKK
Savini
Smithson, PC
Type
ArticleLanguage
enMetadata
Show full item recordAbstract
A 16-week laboratory incubation experiment was conducted to evaluate the effect of
Tithonia diversifolia leaves on the dissolution of Minjingu (MPR) and Busumbu (BRP) rock phosphates in a Kenyan Oxisol. Triple superphosphate (TSP) fertilizer
was included as a positive control. Soil samples were extracted with anion exchange resin (AER) and mixed anion-cation exchange resin (ACER) after 1, 7, 14, 28, 56 and 112 days to estimate plant available P. Soil P fractionation was carried out using solutions of 0.5M NaHCO3, 0.1M NaOH and 1M HC
l. The highest mean AER-extractable P concentrations for BRP and MPR treatments were 6.0 and 20 mg kg-1 respectively; while that of the TSP treatments was 24 mg kg-1. The AER-extractable P concentrations were in the order TSP >MRP > BRP. The ACER-extractable P concentrations were higher than those of AER. Application of tithonia at 10 tons ha-1 in combination with MPR caused a significant (P<0.05) depression in AER-extractable P.
The TSP treatments had the highest NaHCO3-Pi and NaOH-Pi (labile and moderately labile inorganic P) fractions which ranged from 22 to 32% and 45 to 59% of total added P, respectively; followed by MPR treatment which had NaHCO3-Pi and NaOH-Pi fractions ranging from 13 to 22% and 26 to 34% of the total added P, respectively. Addition of tithonia decreased the NaHCO3-Pi and NaOH-Pi fractions from the MPR treatments by 2 to 8%. The RP treatments had the highest HCl-Pi (undissolved RP) fraction.
URI
http://profiles.uonbi.ac.ke/nancy/publications/effect-tithonia-diversifolia-hemsley-gray-biomass-solubility-rock-phosphates-labohttp://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/49772
Citation
The effect of Tithonia diversifolia (Hemsley) A. Gray biomass on the solubility of rock phosphates: A laboratory incubation experiment. Tropical and Subtropical Agro ecosystems..Publisher
University of Nairobi Department of Land Resource Management and Agricultural Technology