Fig. 4
Extraction of root surface area from images and correlation with nematode counts. A A visual representation of the pipeline used for calculating the root surface area. From left to right the features are extracted from the image and a region of interest is defined. Artefacts picked up in the pipeline: A1 Damage to the agar (purple arrow) and a leaf touching the agar (brown arrow). A2 A small particle on the surface of the plastic (pink arrow), clustered roots interpreted as a singular root (blue arrow). B An example of the ability to extract the leaf surface area using colour thresholding. Artifacts are introduced by difference in leaf colour (pink arrow) and damage to the agar (blue arrow). C Two models describing the relationship between number of nematodes and root surface area for two A. thaliana genotypes. The models are described as follows; Columbia 0, Males: y = 5.4 + 5.7 × 10−6x, Females: y = 17.5 + 6.33 × 10−6x. N804585, Males: y = 10 + 2.34 × 10−5x, Females: y = 11 + 1.26 × 10−5x