Trait | Abbreviation | Category | Description |
---|---|---|---|
Shoot dry weight | SDW | Weight | Dry weight of the shoot after drying at 60 °C |
Root dry weight | RDW | Weight | Dry weight of the root after drying at 60 °C |
Shoot-to-root ratio | SRR | Weight | Ratio of the shoot-to-root weight after drying at 60 °C |
Average root width | ARW [cm] | Size | Mean value of the root width estimation computed for all pixels of the medial axis of the entire root system (Fig. 2A) |
Network area | NeA [cm2] | Size | Number of network pixels in the image |
Network length | NeL [cm] | Size | Total number of pixels in the network skeleton (total root length, Fig. 2A) |
Network perimeter | NeP [cm] | Size | Total number of pixels connected to a background pixel (perimeter of the root system, Fig. 2A) |
Network surface area | NeSA [cm2] | Size | Sum of the local surface area at each pixel of the network skeleton, as approximated by a tubular shape whose radius (Fig. 2A) is estimated from the image |
Network volume | NeV [cm3] | Size | Sum of the local volume at each pixel of the network skeleton, as approximated by a tubular shape whose radius (Fig. 2A) is estimated from the image |
Major ellipse axis | MaEA [cm] | Extent | Length of the major axis of the best fitting ellipse enclosing the network (Fig. 2B) |
Minor ellipse axis | MiEA [cm] | Extent | Length of the minor axis of the best fitting ellipse enclosing the network (Fig. 2B) |
Network convex area | NeCA [cm2] | Extent | Area of the convex hull that encompasses the root system (Fig. 2C) |
Network depth | NeD [cm] | Extent | Number of pixels in the vertical direction from the uppermost network pixel to the lowermost network pixel (Fig. 2D) |
Network width | NeW [cm] | Extent | Number of pixels in the horizontal direction from the leftmost network pixel to the rightmost network pixel (Fig. 2D) |
Maximum number of roots | MaNR | Ditribution | After sorting the number of roots crossing a horizontal line from smallest to largest, the maximum is considered to be the 84th percentile value (Fig. 2E) |
Median number of roots | MeNR | Distribution | Result of a vertical line sweep, in which the number of roots that crossed a horizontal line was estimated and then the median of all values for the extent of the horizontal network was calculated |
Network bushiness | NeB | Distribution | Ratio of maximum to median number of roots (Fig. 2E) |
Network length distribution | NeLD | Distribution | Fraction of the network pixel found in the lower two-thirds of the network (Fig. 2 D) |
Network solidity | NeS [cm2 cm−2] | Distribution | Total network area divided by the convex area (Fig. 2C) |
Specific root length | SRL [cm cm−3] | Distribution | Total root length divided by the network volume (Fig. 2A) |
Ellipse axes ratio | EAR [cm cm−1] | Shape | Ratio of the minor to the major axis of best-fitting ellipse (Fig. 2B) |
Network width to depth ratio | NeWDR | Shape | Value of the network width divided by the value of the network depth (Fig. 2D) |