Rapid tissue tests as indicators of yield, plant composition, and soil fertility for corn and soybeans

Abstract

Abstract Corn (Zea mays L.) and soybean (Glycine max (L.) Merr.) rapid tissue test data for N, P, K, Mg, and Mn were obtained at two locations from experimental plots receiving varying rates and combinations of N, P, and K. Soil test, plant composition, and yield data for each plot were also obtained. Relatively precise tissue test readings were obtained by using color standard sheets. A simple correlation matrix was used to relate specific pairs of variables for corn and soybean data at both locations. The correlation analysis of five rapid tissue tests with plant composition, fertility, and yield levels for corn and soybeans revealed several significant positive nutrient‐same nutrient, and many negative cross‐nutrient relationships. Most negative correlations could be explained by ionic antagonism effects. The K tissue test proved to be the most applicable for both crops. Critical sap nutrient concentrations were established for four nutrients, in the case of K through the use of critical plant composit...