Table 1.
Root system architecture (RSA) traits captured by ARIA 2.0 software
| Trait name | Symbol | Unit | Trait description |
|---|---|---|---|
| Total root length | TRL | cm | Cumulative length of all the roots in centimeters |
| Primary root length | PRL | cm | Length of the Primary root in centimeters |
| Lateral root length | LRL | cm | Cumulative length of all lateral roots in centimeters |
| Mean lateral root length | MSL | cm | Mean length of all lateral roots in centimeters |
| TRLUpper | TRLUpper | cm | Total root length of the upper one third |
| TRLLower | TRLLower | cm | Total root length of the lower two third |
| Perimeter | PER | cm | Total number of network pixels connected to a background pixel |
| Depth | DEP | cm | The maximum vertical distance reached by the root system |
| Width | WID | cm | The maximum horizontal width of the whole RSA |
| Diameter | DIA | cm | Diameter of the primary root |
| Lateral root branches | LRB | Count | Number of lateral root branches |
| Nodes of lateral roots | NLR | Count | Number of nodes of lateral roots |
| Independent root branches | IRB | Count | Number of independent lateral root branches |
| Lateral root tip | RTA | Count | Number of lateral root tips |
| Median | MED | Count | The median number of roots at all Y-location |
| MaximumR | MAX | Count | The maximum number of roots at all Y-location |
| Maximum number of roots | MNR | Count | The 84th percentile value of the sum of every row |
| Network area | NWA | Count | The number of pixels that are connected in the skeletonized image |
| Convex area | CVA | cm2 | The area of the convex hull that encloses the entire root image |
| RhizoArea | RHZO | cm2 | Length of 2 mm surrounding the TRL |
| TRArea | TRArea | cm2 | Area of the RSA as observed in the 2D projected view |
| Primary root surface area | PRA | cm2 | Surface area of the primary root |
| TRAUpper | TRAUpper | cm2 | Total root area of the upper one third |
| TRALower | TRALower | cm2 | Total root area of the lower two third |
| Volume | VOL | cm3 | Volume of the primary root |
| Lateral root branching angle | LBA | Angle | Lateral root branching angle near the primary root node |
| Lateral root angles | LRA | Angle | Root angles along the extent of all lateral roots |
| Lateral root tip angle | RTA | Angle | Root angle at lateral root tips |
| Width/depth ratio | WDR | Ratio | The ratio of the maximum width to depth |
| Solidity | SOL | Ratio | The fraction equal to the network area divided by the convex area |
| Bushiness | BSH | Ratio | The ratio of the maximum to the median number of roots |
| Length distribution | LED | Ratio | TRLUpper/TRLower |
| LRL by PRL | LSLPL | Ratio | Number of the Lateral root per unit length of the Primary root |
| Center of mass | COM | Ratio | Center of gravity of the root/Depth |
| Center of point | COP | Ratio | Absolute center of the root regardless of root length/Depth |
| Center of mass (Top) | CMT | Ratio | Center of gravity of the top 1/3 of the root (Top)/Depth |
| Center of mass (Mid) | CMM | Ratio | Center of gravity of the middle 1/3 root (Middle)/Depth |
| Center of mass (Bottom) | CMB | Ratio | Center of gravity of the bottom 1/3 root (Bottom)/Depth |
| Center of point (Top) | CPT | Ratio | Absolute center of the root regardless of root length (Top)/Depth |
| Center of point (Mid) | CPM | Ratio | Absolute center of the root regardless of length (Middle)/Depth |
| Center of point (Bottom) | CPB | Ratio | Absolute center of the root regardless of root length (Bottom)/Depth |