University of Tehran perss Journal of Crops Improvement 2008-8337 18 4 2017 02 19 Evaluation chemical extractants in determination of available potassium for pistachio in calcareous soils of Rafsanjan Evaluation chemical extractants in determination of available potassium for pistachio in calcareous soils of Rafsanjan 935 947 56666 10.22059/jci.2017.56666 FA Samaneh Zadehparizi M.Sc. Student, Soil Science Department, College of Agriculture, Vali-e-Asr University of Rafsanjan - Iran Ahmad Tajabadi Pour Associate Professor, Soil Science Department, College of Agriculture, Vali-e-Asr University of Rafsanjan - Iran Isa Esfandiarpoor Associate Professor., Soil Science Department, College of Agriculture, Vali-e-Asr University of Rafsanjan - Iran Journal Article 2016 01 10 <strong>Potassium is a very important plant nutrient not only because of its large demand, but also because of its important physiological and biological functions in plant. Therefore, understanding of soil potassium status can lead to better use of potassium fertilizers. This study was done to evaluate 10 extractants for estimating available potassium for pistachio in 28 calcareous soils of Rafsanjan in a completely randomized design with three replications in greenhouse conditions in Vali-e-Asr university of Rafsanjan in 2014. Potassium was extracted by 1 M NH₄OAc, 0.01 M CaCl₂,2 M NaCl, 0.1 M HNO₃, boiling 1 M HNO₃, distilled water, 1M NaOAc, Mehlich₁, Mehlich₃ and DTPA-NH₄HcO₃_.The results showed that extraction of K decreased in the order: boiling 1 M HNO₃> 2 M NaCl > 1M NaOAc > Mehlich₃> 1 M NH₄OAc > 0.1 M HNO₃> DTPA-NH₄HcO₃> Mehlich₁> 0.01 M CaCl₂> distilled water. 1M NaOAc was selected as the most suitable extractant for potassium in calcareous soils of Rafsanjan on its high correlation with leaf and shoot K concentration. Multiple regression equations indicated that potassium extracted from the soil dependent to different physical and chemical properties of soil such as amount of clay and cation exchange capacity.</strong> <strong>Potassium is a very important plant nutrient not only because of its large demand, but also because of its important physiological and biological functions in plant. Therefore, understanding of soil potassium status can lead to better use of potassium fertilizers. This study was done to evaluate 10 extractants for estimating available potassium for pistachio in 28 calcareous soils of Rafsanjan in a completely randomized design with three replications in greenhouse conditions in Vali-e-Asr university of Rafsanjan in 2014. Potassium was extracted by 1 M NH₄OAc, 0.01 M CaCl₂,2 M NaCl, 0.1 M HNO₃, boiling 1 M HNO₃, distilled water, 1M NaOAc, Mehlich₁, Mehlich₃ and DTPA-NH₄HcO₃_.The results showed that extraction of K decreased in the order: boiling 1 M HNO₃> 2 M NaCl > 1M NaOAc > Mehlich₃> 1 M NH₄OAc > 0.1 M HNO₃> DTPA-NH₄HcO₃> Mehlich₁> 0.01 M CaCl₂> distilled water. 1M NaOAc was selected as the most suitable extractant for potassium in calcareous soils of Rafsanjan on its high correlation with leaf and shoot K concentration. Multiple regression equations indicated that potassium extracted from the soil dependent to different physical and chemical properties of soil such as amount of clay and cation exchange capacity.</strong> https://jci.ut.ac.ir/article_56666_b90b68a89274ab9b23e1c36872ca04ac.pdf