Water is transported in plants through vascular tissue called xylem. Within the xylem of flowering plants, water is transported through multi-celled hollow tubes called vessels. Most vessels are quite short and water must move from one vessel to another, through microscopic pits in the walls of vessels, to travel long distances within a plant. The many interconnected xylem vessels within the vascular tissue combine to form the xylem vessel network. Although knowledge of xylem vessel structure and function is important in understanding plant water use and water transport, the structure of vessel networks remains little studied. This study will examine xylem vessel network structural traits as they relate to the xylem's ability to efficiently and safely transport water. The overarching hypothesis to be tested is that vessel structure determines xylem hydraulic function; however, the focus of the research will be on three specific structural traits that have been little studied: vessel length, connectivity, and network pit area. Importantly, all three of these traits represent xylem structural features at the tissue level and all are features of the three-dimensional xylem vessel network. This represents an important step beyond traditional xylem structure-function studies that often rely on two-dimensional cross-sectional analyses. The information generated by completion of the proposed study will provide integral knowledge of the links between plant hydraulic structure and function, and, specifically, the influence of vessel network structure on hydraulic function in woody plants.
The project will integrate research on xylem structure and function with community outreach and educational programs designed to involve students from diverse backgrounds and scholastic levels in the scientific process. Research and educational activities will be combined through involvement in a K-12 outreach program, participation in a program for students and teachers from regional high schools and the regional community college, and through involvement of undergraduate and graduate students from the PI's home institution, which is a minority serving institution. Undergraduate and graduate students will participate in data collection, analysis, and the dissemination of results, including presentation of results at national conferences. Additionally, the PI, who is an early career female investigator at a predominantly undergraduate institution, and her students will benefit from active integration of research and teaching.
