Xylem Structure & Function
Does xylem organization influence disease and drought tolerance?
Xylem and phloem networks are complex transport systems that deliver water, nutrients, and signals across long distances in plants. They are also the preferred habitat for a variety of xylem- and phloem-dwelling pathogens. Our research is aimed at developing a better understanding of the tradeoffs faced by plants in assembling transport systems that are both safe and efficient. We use a combination of ecophysiological instruments as well as non-invasive in vivo imaging systems (microCT) to explore the relationships between plant structure and function.
High-resolution microCT scans like this image of a red oak stem (Quercus rubra) allow us to explore the spatial organization of the xylem conduits, their connections to other cell types, and how those connections influence the overall function of the plant.
High-resolution microCT scans also allow us to explore xylem networks from different perspectives, which is generally not possible with other techniques like light microscopy and scanning electron microscopy. Here, a transverse view of red maple (Acer rubrum) shows the distribution of vessels (large white circles) within a matrix of fibers (smaller circular features) and ray cells (vertical striations). Cells within this matrix are interconnected, and microCT imaging in combination with other methods allows us to advance our understanding of how those connections influence plant function over a range of environmental conditions.
Flowers have promoted the rapid diversification of both plants and animals, and they form the basis of the global food supply. Recent evidence suggests that the incredible diversity of flowers apparent today may be due to key innovations that happened early in the evolution of flowering plants. By applying physiological and biomechanical approaches, EF3 will characterize these physiological innovations and elucidate the constraints on floral design that have evolved over the last ~150 million years. Furthermore, it will develop approaches for predicting floral physiological functioning in the future. This is an interdisciplinary collaboration between ecophysiologists Adam Roddy and Craig Brodersen and biomechanics expert Madhusudhan Venkadesan in the School of Engineering and Applied Science (LINK).
Photo credit: Adam Roddy
Leaf Form & Function
We are also interested in how cell shape and organization influence light propagation through leaves. The complexity and diversity of internal leaf anatomy suggests that leaves are finely tuned to specific light environments, and our lab is focused on determining how changes in environmental conditions influence a leaf’s ability to efficiently process light and maximize photosynthesis. Using a custom laser-based chlorophyll fluorescence detection system, we’re able to visualize where light of different directional and spectral quality are absorbed.
