Soil variables vs. mineral analyses of citrus

Abstract

Abstract Leaf and root samples from 120 citrus trees, representing four species from each of six different locations in Egypt, were assayed for mineral elements with an emission spectrograph. The areas represented newly reclaimed lands as well as established orchards in the Nile River Delta. There were symptoms of Zn, Mn, and Fe deficiencies at some, but not all, of the locations. There was a negative correlation between root and leaf concentrations for Mg and positive correlations for B, Fe, P, and K. There were strong positive and negative correlations between plant concentrations of some nutrients and certain soil characteristics (percent soil organic matter, pH in paste, electrical conductivity on a saturation extract, and percent CaCO3). Stepwise regression analyses were therefore made among the soil and plant variables. This test indicated that the soil CaCO3 level was responsible for most of the variation in Fe, Mn, and Al in leaves. Soil organic matter or electrical conductivity of the saturation ...