Split-root system as a useful tool to study woody plant biology

Abstract

AbstractThe split-root system technique has been used to analyse plant biology for several decades, but woody plants have not received enough attention in this experimental approach. Historically, several methods have been developed, ranging from the simplest method of dividing a root into two parts and placing them in separate containers to more complex methods, such as grafting a second root from another plant. Each method has advantages and disadvantages that determine the goals of the experiment. Thus far, research using the split-root system has covered only 62 species of woody plants, mainly to investigate the water shortage effect on water acquisition. Many studies have also considered the significance of functional root-system diversity for plant fertilisation, which allows a better understanding of ion transport regulation mechanisms and some anatomical and functional features of woody plants. Ion uptake and transport have been studied frequently using isotope labelling. The split-root system method also offers interesting possibilities for studying the interactions of plants with other organisms. For example, this method was used to study root colonization strategies by mycorrhizal fungi. The comprehensive analysis of the split-root system technique in this review provides fine-scale information on the future concepts needed to study root-system biology, as the ability of roots to play a range of functions in the plant remains largely untested.