Drought stress is ubiquitous and has played an important selective role in the evolution of plant growth, development, and physiology. It is also a major limiting factor to crop productivity worldwide. This 2010 project will use genome-wide molecular techniques to study the quantitative genetics of adaptation to differences in water availability in the model plant, Arabidopsis thaliana. A major goal of the project is to map and identify genomic regions and characterize genes and gene networks that function in escape, avoidance, and tolerance of drought among plants adapted to habitats spanning extremes of water availability. In addition, new resources will be developed for the study of quantitative genetics in Arabidopsis, including a mapping population and a series of genetic lines capturing genes controlling key components of plant physiology related to drought adaptation. This project builds on the infrastructure of genomic data and tools developed by the Arabidopsis research community, and will link molecular variation of functional genes to evolutionary processes. The ultimate goal of this research is to determine why, as well as how, the Arabidopsis thaliana genome has evolved functional variation in traits important for adaptation to habitats differing in water availability.
The significance of the proposed work in relation to the overall 2010 project objectives is twofold. First, most traits of ecological and agricultural significance are quantitative and influenced by many genes as well as by the environment. Unfortunately, little is known about the molecular genetic details underlying quantitative genetic variation. Understanding the genetics of quantitative variation will be necessary for a complete elucidation of the function of all Arabidopsis thaliana genes. In addition, results of this project will complement ongoing efforts to characterize the genetics of constitutive and inducible traits that enhance stress tolerance in plants. The study of naturally evolved variation is a largely unexplored avenue for understanding the molecular genetic basis of plant stress responses. Secondly, genetic mapping resources, genetic lines, and improved analytical methods developed through the project will facilitate future quantitative genetic studies of Arabidopsis thaliana. The broader impact of the proposed research includes integrated training for students and postdoctoral scholars in molecular genetics, evolutionary biology, physiology, and bioinformatics - skills necessary for the next generation of successful genomic scientists.
All plant materials and associated genotypic data will be made available using The Arabidopsis Information Resource infrastructure (www.arabidopsis.org . Progress and details of particular aspects of the project will be available at the project website (http://orthos.bio.umassd.edu:8080/Arabidopsis/drought), available in October 2004.
