|Pan, William - WASHINGTON STATE UNIV.|
|Bolton, Ronald - WASHINGTON STATE UNIV.|
Submitted to: Western Society of Weed Science
Publication Type: Abstract Only
Publication Acceptance Date: February 6, 1998
Publication Date: N/A
Technical Abstract: The study of root systems of weeds using destructive sampling and manual measurement is time-consuming, expensive and laborious. Rhizotrons allow the examination of spatial and temporal in situ root development. Permanent rhizotron installations provide 2-D images of whole root profiles, but their immobility limits the number of soil-plant systems that can be studied. Over the past three years, we have developed a portable rhizotron and scanning system to provide the capability to study the development of Russian thistle (Salsola iberica) root systems with temporary rhizotron installations that can be inserted at the beginning of the growing season and removed at the end of the growing season. This system combines the full profile images afforded by conventional rhizotrons with the portability of cylinder-based mini-rhizotron systems, and at a fraction of the cost of either system. Covered, rectangular 11 by 33 by 130 cm hollow boxes with a transparent glass face are inserted into a field soil, and a seed or seed piece is planted in the soil adjacent to the glass. The glass face transverses the equivalent distance of one wheat row. Images of roots growing along the glass face are captured with two 120 cm long scans with a portable scanner. Over a 14 day period, the tap root has been observed to extend over 60 cm while the shoot height increased 5 cm. This root observation method is a promising tool for monitoring root morphological development of Russian thistle and other weeds under field conditions.