Characterization of Various Crop Root Hairs Using High Resolution Imaging.

In the dryland agriculture areas of the Pacific Northwest, where wheat (Triticum aestivum) cultivation dominates, farmers have few rotational crops at their disposal.  Oilseed producing crops, along with serving as biodiesel feedstock, may also serve as alternative rotational crops.  Understanding the root structures and their respective rhizospheres of these crops may lead to a better understanding of their function.  A portable rhizotron system was devised by burying high resolution (4800 dpi) desktop scanners in containers filled with field soil and used to characterize root hair length and density under two water availability and phosphorus concentration levels for canola (Brassica napus), camelina (Camelina sativa), flax (Linum usitatissimum),  lentil (Lens culinaris), and wheat.  Marked differences in root structure were observed between species.  Among them, root hair lengths were 0.08, 0.03, 0.04 cm and root hair densities were 828, 2227, and 1752 root hairs cm^-1 respectively for canola, lentil, and wheat.  Variation in root structure among species suggest differences in active root surface area that would  lead to differences in nutrient uptake efficiency and rhizosphere soil volume.