Description
Potassium-use efficiency (KUE) is the outcome of a complex interaction among crop internal physiology, the environment and the management practices imposed on the production system. Four metrics of KUE are discussed: partial factor productivity (PFPK), partial nutrient balance (PNBK), agronomic efficiency (AEK), and recovery efficiency (REK). The chapter also explores genetic modifications to increase KUE by either improving the efficiency of K acquisition from the soil, improving the efficiency with which K is used by the plant to produce harvestable biomass, or both. The chapter also reviews management of K inputs, such as fertilizer form, fertilizer rate, fertilizer placement and application timing, all of which can all affect KUE. Crop management also impacts KUE. Both intra- and interspecic variations in KUE exist, and it may be possible to sequence crops in such a way that species with greater access to non-exchangeable soil K may increase the exchangeable soil K supply and thereby benefit crops with less access to non-exchangeable K.
Table of contents
1 Introduction
2 Potassium dynamics in soils
3 Potassium fertilizer use
4 Assessing potassium-use efficiency (KUE)
5 Improving potassium-use efficiency through breeding
6 Partitioning of potassium to reproductive plant organs
7 Fertilizer management to improve potassium-use efficiency
8 Crop management strategies
9 Conclusion
10 References