Fig. 1.

Root architecture plasticity within an accession (Col-0) broadly recapitulates natural variation quantified across 69 accessions. (A) Root phenotypes of Col-0 plants were grown under five conditions: IAA, CK, ABA, KNO₃, and NH₄Cl plus a control (KCl); roots of three treatment conditions are shown. (B) Root variation between 69 accessions grown under one condition (KNO₃). (C) Landmark template to capture the root system architecture (11). Primary landmarks (black circles) are defined according to corresponding features in all roots; secondary landmarks (white circles) are evenly spaced between primary landmarks (11). (D) Two PCs capture more than 75% of the variation both within Col-0 (PC_COL) and between accessions (PC_VAR). PC1_COL and PC2_COL have high correlation to PC1_VAR and PC2_VAR, respectively. PC1_COL is mainly a size effect, whereas PC2_COL captures mainly root allometry, the length and distribution of lateral roots long the primary root. SD, standard deviation.