Proposed modifications of the diagnosis and recommendation integrated system (DRIS) for interpreting plant analyses

Abstract

Abstract The Diagnosis and Recommendation Integrated System (DRIS) is a unique method of interpreting plant analyses. DRIS includes a number of assumptions which distinguish it from “critical concentration”; approaches, the most important being that ratios of nutrient element concentrations are often better indicators of nutrient deficiency than are simple nutrient element concentrations. Though several workers have shown that DRIS often produces more accurate diagnoses of nutrient element deficiency than conventional approaches, the complexity of the DRIS methodology has discouraged its use. This paper offers three modifications of the DRIS methodology which can simplify its use and interpretation. These include simplified calculation of intermediate functions, modified parameter selection, and modified criteria for predicting response to additional fertilizer.