ACTA AGRONOMICA VOLUME 38. (A MTA AGRÁRTUDOMÁNYI KÖZLEMÉNYEI, 1989)
1989 / 1-2. szám - SOIL SCIENCE AND AGROCHEMISTRY - M. IQBAL MAKHDUM-M. NAWAZ-A. MALIK-FAZAL ILLAHI: Application of electro-ultrafiltration (EUF) method in soil phosphorus determination
Acta Agronomica Hungarica, Vol. 38 (1-2), pp. 3-8 (1989) Soil science and agrochemistry APPLICATION OF ELECTRO-ULTRAFILTRATION (EUF) METHOD IN SOIL PHOSPHORUS DETERMINATION M. IQBAL MAKDHUM, M. NAWAZ, A. MALIK and FAZAL ILLAHI CHOUDHRY CENTRAL COTTON RESEARCH INSTITUTE, MULTAN, PAKISTAN (Received: 22 June 1987; accepted 26 August 1987) The EUF method has established itself as a useful tool for the evaluation of soil fertility. It differs from most other methods of soil analysis in that it not only yields extractable quantities of nutrients but also the rates with which these quantities are desorbed when an external force is applied. The EUF-P values can best be closely correlated with conventional NaHC03 extracted phosphorus (Olsen's method), provided dilution factor is accounted for in calculation of EUF-P in Nemeth's formula. Keywords: Electro-ultrafiltration, EUF-P fractions, rapid determination, soil analysis Introduction The possibility of determining the amount of effectively available and exchangeable nutrients and the desorhing rate of exchangeable nutrients in the soil by means of Electro-ultrafiltration (EUF) method of Nemeth (1972) has been noted with great interest by many soil scientists. Knowledge of such characteristics as EUF-P, K, Na and Ca nutrients dynamics (Nemeth and Makhdum 1981) provides a possibility for considering the dynamics nature of those plant nutrients that are essential for improved regulation of the nutrient supply to the cultivated crops. Following the acquisition of an EUF equipment by the Plant Physiology and Chemistry Section, plans were made to test the EUF method's applicability in the soil analysis and fertilizer recommendations. As a first step, the precision of the method was investigated. EUF extraction removes only certain fractions of the total nutrient content in the soil. These fractions are not absolute quantities in the same way as the total content; the amount of the fraction released depends on the voltage applied and desorption time Therefore, studies on the standardization of the EUF method and its comparison with conventional method were carried out to find its suitability in routine soil phosphorus analysis as a test element. Acta Agronomica Hungarica 38, 1989 Akadémiai Kiadó, Budapest 1»