Plant Root Simulators: An efficient tool for in-field nutrient mapping
Greer, K.J. and J.J. Schoenau. 1995. In Soils and Crops Workshop Proc., pp102-105. Univ. Saskatchewan
Abstract
Plant Root Simulator (PRS™) technology is based on the principle of ion exchange between the soil and a synthetic resin membrane. The name Plant Root Simulator was given to this technology because the mode of action of this type of test is, in many ways, analogous to nutrient ion movement and uptake by plants. The ion exchange mechanism between synthetic resin beads or membranes has been of great utility in assessing the availability of a wide variety of ions existing in the soil (Olness and Rinke, 1994; Van Raij, 1994). The main advantage of this type of testing is that multiple ions can be determined from a single test on a given soil sample. Our research using the PRS™ technology has further advanced this method of testing by developing a system where the ion exchange testing can be done on undisturbed soil, thereby eliminating soil sampling and handling. Such an efficient method of mapping nutrient variability within a field has immediate appeal to those who wish to make variable rate fertilizer application. The concept of "Farming by Soil" or "Precision Farming" is hampered for the most part by the high cost of intensive soil testing (Anonymous, 1994). The purpose of this paper is to describe how the PRS™ system can be used to create nutrient maps and how these levels could guide fertilizer application to obtain a balanced nutrient supply.
