Phenotypic trait relationship. Correlation matrix of phenes and phene aggregates evaluated for bean root phenotypes (a). Correlation matrix of phenes and phene aggregates evaluated for maize root phenotypes (b). The color scale indicates Spearman correlation coefficient between traits (red, negative; blue, positive). Color intensity and size of the circle are proportional to the correlation coefficients between two traits. Correlations between phenes are indicated by the points in the red box; the green box contains the correlations between phene aggregates. BR: basal roots; HBR: hypocotyl-borne roots; PR: primary root; SR: seminal roots; NR: nodal roots; #: number of axial roots; Diam: axial root diameter; LRBD: lateral root branching density; Axial Length: axial root length; Lat Length: lateral root length; Lat Diam: lateral root diameter.