Erin Sparks, University of Delaware
George Chuck, University of California, Berkeley

U.S. agricultural crop production faces the challenge of growing more food on increasingly limited land area and under increasingly harsh environmental conditions. Meeting this production challenge requires new innovations and the identification of new areas to target for increasing plant resilience. One of these overlooked target areas is optimization of aerial root function. Given their central role in water uptake, nutrient use, and anchorage, aerial roots are an important, yet poorly understood area for crop improvement. This proposal focuses on maize (corn), the number one commodity crop in the US, and how targeted changes in aerial root development can lead to functional outcomes. Specifically, this research will identify which root developmental programs can be altered to generate beneficial agronomic results. The outcomes of this basic research will help develop sustainable crop systems, which will enhance scientific knowledge and help secure our food supply. Undergraduate and graduate students will gain interdisciplinary training through research opportunities in the lab, attendance at national conferences, and engagement with the agricultural community through participation in the annual University of Delaware Ag Day event.

This proposal aims to define the fundamental link between root development and function using maize nodal roots as a model system. There are only a few genes known to alter nodal root development and they have not been placed in a larger genetic context that will allow an understanding of root functional consequences. In this proposal, squamosa promoter binding protein (SBP) transcription factors, known regulators of the juvenile-to-adult phase transition, will be used to alter and regulate nodal root development and the functional outcomes will be analyzed. This proposal specifically tests the hypothesis that “SBP genes directly regulate nodal root development to determine nodal root number and alter root function.” Using brace roots as a model for nodal root development, the researchers will test this hypothesis by quantifying the root phenotypic outcomes of modulating sbp expression, defining the genetic mechanisms underlying SBP-regulation of nodal root development, and determining the functional consequences of these root phenotypic changes. The results from this proposal will provide a foundational understanding of how modulating root development can elicit targeted root functional outcomes.

Publications Associated with this Award

Sparks EE. “Maize Plants and the Brace Roots that Support Them” Tansley Insight, New Phytologist, 2023 Jan. https://doi.org/10.1111/nph.18489