Edgar P Spalding

Achieving a better understanding of seedling growth and development is our team’s overarching goal. In particular, we want to know how light, gravity, temperature, and other variables influence the vital processes that produce an independent seedling from a dormant embryo within a seed. The plant hormone auxin (indole-3-acetic acid) is a mobile coordinator of many of these processes. Understanding its transport mechanism will further our understanding of the whole. We believe posing auxin transport questions in a rigorous thermodynamic framework and making electrophysiological measurements on isolated transporters and mutant plants lacking them will produce an enabling new view of many seedling phenomena.

Our investigations typically employ methods from the fields of molecular biology, genetics, electrophysiology, and digital image analysis. Arabidopsis thaliana and maize are the primary species we use. Increasing measurement throughput is key to leveraging the genetic resources built up around these model systems. For this reason, we develop computational tools that automate measurements of phenotypes. The beauty in a measurement well made becomes power in the many.

A jargon-free essay about the computational work published in the Wisconsin State Journal may be found here.
My biography prepared for the occasion of becoming an ASPB Legacy Society Founding Member is here.
Our team engages in community outreach as described here.
Teaching is an important component of my job. I teach an upper-level course in plant physiology each spring. Each fall I co-teach general botany.

some representative publications
Che X, Splitt BL, Eckholm MT, Miller ND, Spalding EP (2022) BRXL4-LAZY1 interaction at the plasma membrane controls Arabidopsis branch angle and gravitropism. The Plant Journal online early

Yoshihara T, Miller ND, Rabanal FA, Myles H, Kwak I-Y, Broman KW, Sadkin B, Baxter I, Dilkes BP, Hudson ME, Spalding EP (2022) Leveraging orthology within maize and Arabidopsis QTL to identify genes affecting natural variation in gravitropism. Proceedings of the National Academy of Sciences USA 119: e2212199119

Varela JI, Miller ND, Infante V, Kaeppler SM, de Leon N, Spalding EP (2022) A novel high-throughput hyperspectral scanner and analytical methods for predicting maize kernel composition and physical traits. Food Chemistry 391: 133264

Deslauriers SD, Spalding EP (2021) Electrophysiological evidence of synergistic auxin transport by interacting Arabidopsis ABCB4 and PIN2 proteins. Plant Direct 5: e361

Yoshihara T, Spalding EP (2020) Reversing the direction of Arabidopsis stem gravitropism by altering two amino acids in AtLAZY1. Plant Physiology 182: 1039-1051

Wu G, Miller ND, de Leon N, Kaeppler SM, Spalding EP (2019) Predicting Zea mays flowering time, yield, and yield components by analyzing aerial images. Frontiers in Plant Science 10: 1251

Miller ND, Stelpflug SC, Kaeppler SM, Spalding EP (2018) A machine vision platform for measuring imbibition of maize kernels: quantification of genetic effects and correlations with germination. Plant Methods 14: 115

Yoshihara T, Spalding EP (2017) LAZY genes mediate the effects of gravity on auxin gradients and plant architecture. Plant Physiology 175: 959-969

Miller ND, Haase NJ, Lee J, Kaeppler SM, de Leon N, Spalding EP (2017) A robust, high-throughput method for computing maize ear, cob, and kernel attributes automatically from images. The Plant Journal 89: 169-178

Wu G, Carville JS, Spalding EP (2016) ABCB19-mediated polar auxin transport modulates Arabidopsis hypocotyl elongation and the endoreplication variant of the cell cycle. The Plant Journal 85: 209-218

Heckwolf S, Heckwolf M, Kaeppler SM, de Leon N, Spalding EP (2015) Image analysis of anatomical traits in stalk transections of maize and other grasses. Plant Methods 11: 26

Cho M, Henry EM, Lewis DR, Wu G, Muday GK, Spalding EP (2014) Block of ATP-binding cassette B19 ion channel activity by 5-nitro-2-(3-phenylpropylamino)-benzoic acid impairs polar auxin transport and root gravitropism Plant Physiology 166: 2091-2099

Moore CR, Johnson LS, Kwak I-Y, Livny M, Broman KW, Spalding EP (2013) High-throughput computer vision introduces the time axis to a quantitative trait map of a plant growth response. Genetics 195: 1077-1086

Vincill ED, Clarin AE, Molenda JN, Spalding EP (2013) Interacting glutamate receptor-like proteins in phloem regulate lateral root initiation. The Plant Cell 25: 1304-1313

Spalding EP, Miller ND (2013) Image analysis drives a renaissance in growth measurement. Current Opinion in Plant Biology 16: 100-104

Moore CR, Gronwall DS, Miller ND, Spalding EP (2013) Mapping quantitative trait loci affecting Arabidopsis thaliana seed morphology features extracted computationally from images. G3: Genes, Genomes, Genetics 3: 109-118 featured on the cover

Spalding EP (2013) Diverting the downhill flow of auxin to steer growth during tropisms. American Journal of Botany 100: 203-214

See the Science Nation video about our Phytomorph project, related articles in Popular Science and Vision Systems Design, and an article about our use of high-throughput computing.