A transcriptomic approach to uncovering the molecular mechanisms of maize nodal root growth maintenance during drought stress in the field
No Thumbnail Available
Authors
Meeting name
Sponsors
Date
Journal Title
Format
Thesis
Subject
Abstract
Drought is the most important factor limiting crop production across the globe. Therefore, understanding how plants adapt and survive drought conditions is critical for improving food production with lower water input. One such survival mechanism is the maintenance of root elongation, even in very dry environments. In maize, the nodal root system comprises the majority of the root length of the mature plant and is therefore critical for sustaining water uptake. The shoot-borne nodal roots have the ability to maintain growth at low water potentials that inhibit growth of other plant organs. Despite the vital nature of this response to drought survival, the physiological and molecular mechanisms underlying this ability are poorly understood and are the focus of this work. To understand this phenomenon, we are utilizing transcriptomics to explore changes of the maize nodal root growth zone under irrigated and water-limited conditions in two inbred lines, FR697 and B73. These lines have contrasting abilities to maintain nodal root growth under water stress. We are characterizing these changes in the field utilizing a rainout shelter for precise control of drought imposition. This approach allows for the determination of the molecular and physiological changes during "real world" drought conditions. We have identified potential gene candidates involved in nodal root growth maintenance from data collected during two field seasons. In the FR697-specific transcript list we found an enrichment of cell wall modifying proteins, sugar and water transporters. We could speculate these transcript candidates could be assisting in the enhanced nodal root growth observed for this genotype. In the B73-specific transcript list, we found ROS metabolism being heavily enriched, which could play a role in cell production and the inhibition of root growth observed for B73 during water stress. When we compared the transcripts that are enriched in both genotypes, we found ABA to be a strong player during water stress. In all, after the careful design and execution of this experiment, we highlighted many avenues for exploration into the molecular mechanisms of nodal root growth maintenance during drought in the field.
Table of Contents
DOI
PubMed ID
Degree
Ph. D.