Peter Melcher (Biology) presented a talk at the American Society of Plant Biology Northeastern sectional meeting in Rhode Island, March 30th, 2014.
Title of talk "A new approach to measure hydraulic resistance in plants"
Measuring xylem hydraulic resistance in plants is a common procedure that relies on well-established methods. Results from comparative measures of xylem hydraulic conductivity using traditional and a new protocol on eight woody species will be discussed. The new method was developed to reduce errors associated with samples that are: shorter than their xylem conduit lengths; and from fluid moving through artificially created flow paths when measurements are made on samples that are excised on both ends, such as fluid moving through xylem conduits located in older vascular growth rings that may not be conducting in the intact samples. The new method produced much lower values of hydraulic conductivity in 7 of the 8 species studied. However, there was a large species-dependent range observed between the two methods. For example, the new method produced conductivity values that were two times lower for Acer rubrum samples compared to traditional hydraulic methods. And in some species, the differences between the two methods were only about 10%. For Robinia pseudoacacia conductivity values were found to be the same for both methods. Reasons for these variations will be discussed.
Meeting website: http://web.uri.edu/neaspb/