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Phosphorus and Potassium Tissue Testing Recommendations Available in New Publication

Antonio Mallarino, John Sawyer, Professors, Department of Agronomy, Iowa State University
June 28, 2018

The practice of conducting tissue testing for phosphorus and potassium in corn and soybean is a relatively new tool in Iowa crop production. While soil testing has been widely used for decades, proper tissue testing recommendations are still emerging.

A new publication from Iowa State University Extension and Outreach discusses the results of tissue testing research and interpretation at Iowa State University. The publication "Phosphorus and Potassium Tissue Testing in Corn and Soybean" (CROP 3153) provides interpretations specific for Iowa’s growing conditions.

Iowa research into tissue testing in previous decades has shown that either this was not a reliable practice or the research wasn’t sufficient. As interest in tissue testing has grown in the last few years, there was a need for additional research in order to determine the value of tissue testing and develop guidelines on how to interpret test results.

The resulting publication is the first interpretations for tissue testing specific to Iowa, and is based on 66 site-years of research results for phosphorus and 119 site-years for potassium.

Read more.




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