Fig. 10

Minirhizotron root image of spring barley roots appearing with the presence of dead roots of red fescue with root length quantified by grid counting and by automated multispectral image analysis. a RGB type image with a grid structure applied for root quantification as performed in this study. Manual observers counted the number of times living white spring barley roots intersected with superimposed gridlines (red circles). b Transformed image using normalized canonical discriminant analysis (nCDA) c Final centerline extracted root length after noise removal using a vesselness enhancement filter