Abstract
Image analyzing software aided simple quantitative
analysis method for the formation of root hairs in
lettuce (Lactuca sativa L. cv. Grand Rapids) seedlings
was newly developed. Low-magnification microscopic
images of main roots and root hairs were
first recorded on a magneto-optical disk using a
CCD color camera and an image recorder. Recorded
images were next converted to monochromatic
gray scale images, then binarized to black
and white images using image analyzing software.
Depending on the threshold level for the binarization,
an image of either the main root plus root
hairs or just the main root was extracted as a black
image. Next, “exclusive or” between the image of
the main root plus root hairs and that of the main
root was calculated. The thus-obtained image was
next inverted, and the total number of black pixels
was calculated as equivalent to the total amount of
root hair. The total number of black pixels included
in the long slender window along the surface of the
main root in the image of the binarized root hairs
plus main root was used to represent the density of
the root hairs. Both values showed good correlation
to the values determined by manual measurement
using magnified printed images. This method made
it possible to analyze root hair formation quickly
and accurately.
