Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/29/2000
Publication Date: 11/1/2000
Citation: LORY, J.A., POTE, D.H., ZHANG, H., SCHARF, P.C. 2000. INITIAL SOIL TEST PHOSPHORUS (P) EFFECT ON THE REACTION RATE OF ADDED P. MEETING ABSTRACT. p. 317.
Technical Abstract: Runoff from applied phosphorus may depend on initial soil test phosphorus (STP) level. This laboratory experiment investigated the hypothesis that STP level has no effect on the reaction rate of applied phosphorus with the soil. We obtained 9 soils (3 soil types X 3 STP levels); initial Mehlich III STP levels ranged from agronomic to greater than 1000 mg/kg because of a history of poultry or beef manure applications. Three replicates of 3 treatments (100 kg P/ha as potassium phosphate or poultry litter or a 0 P control) were applied in a randomized block design. The soils were samples 0, 2, 4, 8, 16, 32, 64, and 128 days after P application and analyzed for water soluble P and Mehlich III P. Initial STP level had no significant effect on the increase in water soluble P from applied P for an acidic Missouri soil but the interaction with initial STP level was significant for the calcareous Texas soil. Applied P resulted in lower increases in water soluble P in the high STP calcareous soil.