Shiraz University Iran Agricultural Research 1013-9885 34 1 2015 03 21 Development of an alternative to the olsen test for determining corn plant-available phosphorus in calcareous soils توسعه روش جایگزین آزمون اولسن جهت تعیین فسفر قابل جذب ذرت در خاک‌های آهکی 92 104 3096 10.22099/iar.2015.3096 EN Mohammad Maghsoodi Department of Soil Science, College of Agriculture, University of Tabriz, Tabriz, I. R. Iran A Reyhanitabar Department of Soil Science, College of Agriculture, University of Tabriz, Tabriz, I. R. Iran Nosratolla Najafi Department of Soil Science, College of Agriculture, University of Tabriz, Tabriz, I. R. Iran Journal Article 2013 12 31 In this research, several chemical extractants and modified Olsen methods were studied in 25 surface-calcareous soils (0-30 cm) for determining available phosphorus (P) for corn (<em>Zea mays </em>L.) plant. In this experiment, the highest correlation was obtained between extracted P by Olsen and Colwell methods (NaHCO<sub>3</sub>-extractable P) and dry weight of corn shoot (r =0.67 and 0.75, p Calcareous soils corn Olsen test Phosphorus https://iar.shirazu.ac.ir/article_3096_200fb83796aa7c775e92ff86cb6bc96d.pdf