caa a22 4500 477110436 CHVBK 20180405111607.0 cr unu---uuuuu 170330e19960101xx s 000 0 eng 10.1007/BF00011581 doi (NATIONALLICENCE)springer-10.1007/BF00011581 Utilization of organic phosphorus in calcium chloride extracts of soil by barley plants and hydrolysis by acid and alkaline phosphatases [Elektronische Daten] [B. Seeling, A. Jungk] Organic phosphorus is often a major part of total phosphorus in soil solution. The role of this fraction as a P source for plants and the mechanism involved in its transfer from soil to plant is still unclear. We studied the utilization of organic phospharus in 0.01 M calcium chloride extracts by barley and its hydrolysis by isolated acid and alkaline phosphatases. Calcium chloride extracts were used as a nutrient solution in 24 hrs assays. Concentration of organic and inorganic P in equilibrium calcium chloride extracts was 7.8 and 1.8 µmol P L-1, respectively, which was similar to the soil solution P concentration. When soil microbial biomass was destroyed by autoclaving, organic P concentration increased to 64.8 µmol P L-1 whereas the inorganic P was hardly changed. Inoculation of the autoclaved soil with non-sterile soil and incubation for 5 days decreased the organic P concentration to 27.9 µmol P L-1 but did not change inorganic P. In this study barley plants utilized organic P from all extracts. The greatest reduction of organic P concentration occurred in fresh extracts of the autoclaved soil. Inorganic P was depleted to traces in all extracts. Organic P was hydrolyzed by isolated acid and alkaline phosphatases. We conclude that organic P in soil solution is a heterogeneous pool of organic P compounds originating from microbial biomass. Its initial availability to plants was nigh but its susceptibility to phosphatase hydrolysis was quickly reduced but not completely lost. Kluwer Academic Publishers, 1996 barley nationallicence Hordeum vulgare nationallicence microbial biomass P nationallicence phosphatases nationallicence soil solution P nationallicence Seeling B. JCRISAT Asia Center, 502 324, Patancheru, A. P., India aut Jungk A. Institute for Agricultural Chemistry, Georg-August University, von Siebold-Str. 6, D-37075, Göttingen, Germany aut Plant and Soil Kluwer Academic Publishers; gopher://gopher.wkap.nl 178/2(1996-01-01), 179-184 0032-079X 178:2<179 1996 178 11104 https://doi.org/10.1007/BF00011581 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00011581 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Seeling B. JCRISAT Asia Center, 502 324, Patancheru, A. P., India aut NATIONALLICENCE 700 1- Jungk A. Institute for Agricultural Chemistry, Georg-August University, von Siebold-Str. 6, D-37075, Göttingen, Germany aut NATIONALLICENCE 773 0- Plant and Soil Kluwer Academic Publishers; gopher://gopher.wkap.nl// 178/2(1996-01-01), 179-184 0032-079X 178:2<179 1996 178 11104 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer