Principal investigators: Christopher Topp, Donald Danforth Plant Science Center; Andrew Leakey, University of Illinois; Ivan Baxter, USDA-ARS
Associated with: National Science Foundation
National Science Foundation Award number: (PGRP) IOS-1638507
Realizing the enormous potential of root systems to boost and stabilize crop yields under stress and to reduce unsustainable levels of fertilizer use will require a thorough understanding of their genetics and physiology. Image based phenotyping has enabled high-throughput and accurate measurements of roots, but despite many new and promising methods, each has inherent tradeoffs that limit their individual power. This project employs an integrated root phenomic and physiological profiling approach to resolve the genetic basis and functional consequences of maize root architecture. It will profile the root architecture of two maize populations in four complementary ways: 3D/4D imaging of young plants in a gel based system, optical and X-ray based imaging of root crowns excavated from the field, and minirhizotron imaging of roots growing across the soil profile in the field. Quantitative genetic analyses from each of these methods will allow identification of the genes controlling these traits. Additionally, this integrated analysis of identical genotypes will generate the most comprehensive comparison of root phenotyping methods to date. One population will be selected from screening of the NAM parent lines in the first two years of the project, the other population will be the Illinois Protein Strain Recombinant Inbreds (IPSRIs). Over five years, this approach will address the following aims:
1. Identify genes driving phenotypic variation of root architecture,
2. Identify genes controlling phenotypic plasticity of root architecture to nitrogen supply,
3. Determine the functional impacts of root architecture on plant nitrogen status, elemental content and seed quality.