A Systems Approach to improving Abiotic Stress Tolerance in Peanut
Lack of suitable water is the single-most important limitation to agricultural production in most regions around the world. Irregular rainfall, global climate trends, depletion of groundwater supplies, and competition for freshwater with rapidly-expanding urban areas all place significant constraints on resources for agricultural productivity. Direct improvement in crop germplasm and crop management schemes that results in increased yields under limited input (primarily water) is critical if we are to meet future demands of food and fiber production. The best prospect for meeting future production demands is an integrated program, employing molecular, physiological, and breeding resources in combination with new, field-based approaches for selection that directly address optimized yield in resource-limited production environments.
Our long-term goals are to understand biological adaptations to abiotic stresses that occur in production systems and to develop stress-tolerant cultivars.
For this proposal, we will 1) investigate the physiological and molecular basis of crop response to abiotic stress that occurs in limited-input production systems, and the role of stress acclimation in this response, 2) develop straightforward crop management protocols that maximize plant acclimation capacity and effective water use while maintaining economic and environmental sustainability, and 3) use physiological and molecular methods to assist in selection and development of abiotic stress-tolerant cultivars. Hypotheses include: 1) peanut germplasm pools possess a wealth of novel genes and phenotypes for abiotic stress response and stress acclimation that can be exploited for improving stress tolerance and 2) a combination of laboratory and field-based screening under field-relevant production scenarios will result in successful identification of molecular and morphological traits for improved stress tolerance via breeding or direct gene transfer.
Here, we propose to identify diverse peanut genotypes showing differences in acclimation capacity for water-deficit and thermal stress that arises in production settings using remote-sensing-based phenotyping. Transcriptome analysis (RNA-Seq) will be used to identify molecular mechanisms underlying the acclimation response and fundamental differences between contrasting genotypes. Successful completion of this work will provide insight into the underlying molecular mechanisms controlling peanut abiotic stress responses and the impact of those responses on whole-plant physiology and yield. The identification of novel sources of genetic material for breeding stress tolerance in peanut and generation of new transcriptome data will provide valuable sequence information to the peanut and legume communities and scoreable polymorphisms in populations segregating for abiotic stress tolerance. Additionally, a refined, user-ready irrigation scheduling model for primed acclimation production will be developed for both the Southwest and Southeast U.S. (and similar production regions in other countries) using currently available sensing technology.