RHIZOMETRICS: A REVIEW OF THREE IN SITU TECHNIQUES FOR OBSERVATION AND MEASUREMENT OF PLANT ROOT SYSTEMS IN CONTAINERS
Rhizometrics is a term derived from rhizo- (rhizosphere) and -metrics (series of parameters or measures of quantitative assessment used for measuring, comparisons or tracking performance or production), to describe several methods either developed or examined by North Carolina State University to observe and quantify root growth of plants in containers. Three new techniques have been developed and/or investigated as potential new methods of quantifying root growth; 1) Mini-Horhizotron; 2) Rhizometer; and 3) Hydraulic Conductance Flow Meter (HCFM). First, the mini-Horhizotrons have a clear, three-arm configuration suitable for observing root growth of small container plant material. The clear arms allow for visible access and measure¬ments of plant roots. Potential measurements include root length, quantity of root hairs, and root architecture. Second, the Rhizometer is made from a clear cylinder that is 7.6 cm tall x 7.6 cm inside diameter, which allows for visible observations of root systems and they can be fitted in the North Carolina State University Porometer for in situ measurements of the influence of root growth on physical properties in containers during crop production. Thirdly, the HCFM is an apparatus that measures root and shoot conductance based on pressure and water flow through the roots, in the opposite direction of normal transpiration under quasi-steady-state conditions. Conductance values are directly indicative (and correlated) with root mass. These Rhizometric techniques are novel methods of observing and quantifying root growth and potentially identifying ways of improving root growth productivity and efficiency to maximize crop growth. These techniques have also been used to quantify root growth differences between/among various substrates. A summary of the initial experiments testing the usefulness of these three techniques for quantifying undisturbed root growth have yielded promising results.
Judd, L.A., Jackson, B.E. and Fonteno, W.C. (2014). RHIZOMETRICS: A REVIEW OF THREE IN SITU TECHNIQUES FOR OBSERVATION AND MEASUREMENT OF PLANT ROOT SYSTEMS IN CONTAINERS. Acta Hortic. 1034, 389-397
hydraulic conductance flow meter, mini-Horhizotrons, Rhizometer, rhizosphere