Research Plant Environmental Tolerance
The Plant Abiotic Stress team at Texas A&M AgriLife Research – Dallas focuses on revealing the mechanisms of plant response and adaptation to adverse environmental conditions (abiotic stress), such as drought, extreme temperatures, high soil salinity, and soil nutrient deficiency. The ultimate goal of the team is to use research-generated knowledge to breed and bioengineer the next-generation of hardy plants for urban (lawn and garden) and agricultural applications.
Genetic basis of plant drought tolerance
On a global scale, drought is one of the most devastating and most common forms of natural disaster for agriculture. In Texas, a vast area is classified as semi-arid or arid with limited rainfall. How can certain plants survive in water-limited environments? Can we irrigate less while ensuring plant growth and productivity? Or, can we breed hardier plants that thirst less for water? To address these and related questions, we must understand how plants respond to drought (soil water deficit) and to demystify the genetic makeup that determines their drought tolerance. Our team uses state-of-the-art genetic screens and other approaches to uncover the genetic basis that dictates leaf transpiration regulation and whole plant adaptation to drought stress. The genes identified in the study will be tested for their effectiveness in improving drought resistance in turf grass and agricultural plants.
Root adaptation to drought stress
The plant root system can be an early sensor, and likely, also the first responder to soil water shortage. How can roots sense water status in the soil? What are their possible responses in case of soil water shortage? It is expected that plants with deeper roots are advantageous over those with shallow roots under drought stress. But what determines the growth direction and depth of the root system? Using integrative genetic, molecular biological, and physiological approaches, we are addressing these questions by identifying the genes that control various root responses to soil water deficiency. We hope that by manipulating expressions of these genes, we can help plants to establish a more robust root system that mitigates the impact of drought stress on plants.
Gene regulation under abiotic stress
One major response of plants to environmental stress (abiotic stress) is the activation of a large number of stress-responsive genes. Some of these gene products can mitigate the damaging effects caused by stress, and thus increase plant stress tolerance. As such, it is of critical importance to uncover the processes from stress signal sensing to the transcriptional activation of stress genes. Using molecular genetics, biochemistry, and genomics approaches, we have identified a number of genes important for the regulation of stress-responsive targets. Furthermore, the effects of these gene products on mRNA and non-coding RNA metabolism are also being investigated. Using ChIP-seq, RNA-seq, and other high throughput sequencing techniques, combined with proteomics approaches, we are revealing how specific sets of genes are activated by the general transcription machinery (i.e., RNA polymerase II) in response to stress and stress hormone stimuli, and how the stress-responsive transcripts are processed, translated or eventually, degraded. Physiological studies are also being conducted to reveal the roles of these proteins or non-coding RNAs in improving plant stress resistance.