High-throughput phenotyping identifies plant growth differences under well-watered and drought treatments

Abstract

The ability to screen larger populations with fewer replicates and non-destructive measurements is one advantage of high-throughput phenotyping (HTP) over traditional phenotyping techniques. In this study, two wheat accessions were grown in a controlled-environment with a moderate drought imposed from stem elongation to post-anthesis. Red-green-blue (RGB) imaging was performed on 17 of the 22 d following the start of drought imposition. Destructive measurements from all plants were performed at the conclusion of the experiment. The effect of line was significant for shoot dry matter, spike dry matter, root dry matter, and tiller number, while the water treatment was significant on shoot dry matter and root dry matter. The temporal, non-destructive nature of HTP allowed the drought treatment to be significantly differentiated from the well-watered treatment after 6 d in a line from Argentina and 9 d in a line from Chile. This difference of 3 d indicated an increased degree of drought tolerance in the line from Chile. Furthermore, HTP from the final day of imaging accurately predicted reference plant height (r=1), shoot dry matter (r=0.95) and tiller number (r=0.91). This experiment illustrates the potential of HTP and its use in modeling plant growth and development.