02156naa a2200241 a 450000100080000000500110000800800410001910000190006024501070007926000090018652014810019565000150167665000140169165000190170565000130172465300120173765300130174965300100176265300100177270000240178270000260180677300820183213552662016-09-14       1984    bl uuuu     u00u1 u    #d1 aLOGANATHAN, P.  aEvaluation of the phosphorus status of some coconut growing soils of Sri Lanka.h[electronic resource]  c1984  aThe phosphorus status of 58 soil samples representing 15 soils series and four soil orders (Ultisol, Entisol, Alfisol and Oxisol) in the major coconut-growing regions of Sri Lanka was evaluated by determining the available P extracted by methods of Olsen, Bray and Kurtz numero 1, Bray & Hurtz numero 2 and NH4 OAc(pH 4.8) and the various P forms. Total P in the soils ranged from 37 to 338 mg/kg with organic P and active P constituing only about 20 and 50% of the total P respectively. In general the sandy soils of the Entisols and Oxisols had lower total and organic P but higher active and available P than the rest. The relative abundance of the various inorganic P forms was generally in the decreasing order of inactive P, Fe-P, Al-P and Ca-P, Al-P and Ca-P were positively correlated with percentage sand and negatively correlated with percentage silt and percentage clay whereas total P and organic P had the opposit trend. Available P extracted by the four methods was very low in almost all soils except some of the sandy soils (Entisols) which had marginal to moderate P concents. They are positively correlated with Al-P, Ca-P percentage sand and negatively correlated with percentages of slit, clay and organic carbon. Phosphorus concentrations (0.074-0.116%) in the 14th leaf of coconut at the soil sites were all lower than the critical leaf-P concentration (0.120%). Leaf-P correlations with Bray & Kurtz numero 2-P and NH4 OAc-P were significant (P&lt0.05).  aphosphorus  aSri Lanka  aCocos Nucifera  aFósforo  aCoconut  aCoqueiro  aSoils  aSolos1 aDAYARATNE, P. M. N.1 aSHANMUGANATHAN, R. T.  tJournal of the Coconut Research Institute of Sri Lankagv. 2, p. 29-43, 1984.