Roots can be arranged to reduce overlap and crossing while floating in the trays.
Prior to acquiring root images, roots may be stained . Staining can increase contrast in the image, which improves the accuracy of measurement, and can improve the determination of root diameter. However, it is an additional step, which requires more time and handling of samples. Staining may especially be problematic when plants are very small and the entire root is being scanned as staining could prevent further chemical analysis of tissue. We recommend a preliminary trial where a sample is scanned before and after staining to determine if staining is necessary or not. We have successfully used Neutral Red (0.162 g/L in water) for root staining.
Roots are floated in water in acrylic trays on the scanner. This allows the roots to be arranged to reduce overlap and crossing of roots. We use plastic forceps and very fine plastic pipettes as tools. This is delicate work; good lighting and steady hands are helpful.
