Advances and considerations in technologies for growing, imaging, and analyzing 3-D root system architecture

Authors: Pineros, Miguel; LARSON, BRANDON - Boyce Thompson Institute; SHAFF, JON - Cornell University; Schneider, David; FALCAO, ALEXANDRE - Universidade De Campinas (UNICAMP); LIXING, YUAN - China Agricultural University; CLARK, RANDY - Cornell University; Craft, Eric; Davis, Tyler; PRADIER, PIERRE-LUC - Boyce Thompson Institute; Liu, Jiping; ASSARANURAK, ITHIPONG - Cornell University; SUSAN, MCCOUCH - Cornell University; STURROCK, CRAIG - University Of Nottingham; BENNETT, MALCOM - University Of Nottingham; Kochian, Leon

Submitted to: Journal of Integrative Plant Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/16/2015
Publication Date: 3/1/2016
Citation: Pineros, M., Larson, B., Shaff, J., Schneider, D.J., Falcao, A., Lixing, Y., Clark, R.T., Craft, E.J., Davis, T.W., Pradier, P., Liu, J., Assaranurak, I., Susan, M., Sturrock, C., Bennett, M., Kochian, L.V. 2016. Advances and considerations in technologies for growing, imaging, and analyzing 3-D root system architecture. Journal of Integrative Plant Biology. 58(3):230-241.

Interpretive Summary: There is a growing understanding about how important root systems are to crop traits such as nutrient and water acquisition and utilization, and tolerance to toxic metals in the soil. For example, with regards to tolerance to low phosphorous (P) in the soil, it is now known that root system architecture (RSA), or where the plant places different roots in the soil within the entire root system, plays a key role in the ability for the plant to efficiently acquire P from low P environments. Therefore, for the research detailed in this paper, we investigated a series of improvements we have made to a system to: 1) grow root systems of crop plant species in transparent media (gellan gum or hydroponic media) to maintain the root architecture but enable digital aiming of the root systems; 2) digitally acquire one hundred 2-D images of the entire root system of individual plants in a rapid manner, and 3) use custom designed software to reconstruct the one hundred 2D images into a 3-D model of the root system of individual plants, and then quantify a number of different root architecture, morphology and topology traits of the entire root system. The efficacy and accuracy of imaging root systems grown in gellan gum vs. hydroponics was compared, as well as the quantitation of roots grown in soil-like media and soils. Both the importance of these improveme4nts and the need for further improvements to improve the throughput, accuracy and precision of these root imaging methods is discussed.

Technical Abstract: The ability of a plant to mine the soil for nutrients and water is determined by how, where, and when roots are arranged in the soil matrix. The capacity of plant to maintain or improve its yield under limiting conditions, such as nutrient deficiency or drought, is affected by root system architecture, the 3-dimensional distribution of roots in the soil. The ability to track and quantify these root system attributes in a dynamic fashion are very important for assessing desirable genetic and physiological traits. Recent advances in imaging technology and phenotyping software have allowed for greater progress in describing root system architecture. We have designed a hydroponic growth system which retains the 3-dimensional root system architecture (RSA), while allowing for aeration, solution replenishment, and the imposition of nutrient treatments throughout the growth experiment. The simplicity and elasticity of the system allows for minimal preparation, system modifications to suit root system architecture, and better throughput. This paper outlines some of the recent improvements and innovations in growth and imaging systems which allow for greater sensitivity, higher efficiency, and growing conditions for plants that more closely mimic those found under field conditions.