This document discusses using maximum dilution and accumulation curves to convert nutrient uptake of nitrogen, phosphorus, and potassium to crop yield. It explains that physiological nutrient use efficiency curves relate root yield to nutrient uptake, with maximum and minimum efficiency parameters for each nutrient. An example is given of how the curves would show maximal dilution of phosphorus and maximal accumulation of nitrogen and potassium under phosphorus deficiency but ample supply of nitrogen and potassium.