Recipient Organization
OHIO STATE UNIVERSITY
1680 MADISON AVENUE
WOOSTER,OH 44691
Performing Department
Horticulture and Crop Science
Non Technical Summary
Genetic variation plays an important role in a number of critical issues facing agriculture. Evolutionary processes, both natural and human-mediated, control patterns of genetic variation, and thereby future performance, in cultivated and related wild species. Climate change will alter abiotic factors, such as temperature, precipitation, and CO2 levels, thereby affecting agricultural production, including where landrace (traditional) crop varieties adapted to current local conditions are commonly used. It is imperative to understand the patterns of adaptive and neutral genetic diversity found in crop centers of diversity (e.g., Mexico for maize and chile pepper) and try to discern how these crops will respond to climatic challenges through altering their growth, morphology, or developmental timing (i.e., phenotypic plasticity) or changing evolutionarily (i.e., adaptation). Clarifying how crop diversity has responded to selection in the past (e.g., during domestication) and continues to do so, will help illuminate the capacity of crops to adapt to future climates. While rooted largely in Mexican collections, this work provides understanding for how to adapt US agriculture to climate change by managing crop genetic resources. Our work in these areas requires field experiments with diverse genetic materials under multiple environmental conditions, as well as manipulative experiments performed under more controlled conditions. Phenotypic work will be combined with physiological and molecular genetic analysis (genetic sequencing of DNA and RNA) to better clarify the patterns of genetic structure and assess genes of interest for adaptation to environmental variation. Clarifying how manipulation of genetic diversity can boost ecosystem functions (e.g., weed control, productivity) may augment the resilience of ecosystems in the face of climate or land use change. Field and controlled experiments investigating and manipulating genetic variation will be used to clarify the impacts of genetic diversity on important functions.
Animal Health Component
5%
Research Effort Categories
Basic
90%
Applied
5%
Developmental
5%
Goals / Objectives
Agriculture faces a number of challenges in the 21st century, including maintaining or increasing productivity under conditions of climate change; reducing the environmental impact of production; and managing crop genetic diversity for future use. It is the responsibility of public scientists to explore the basic processes underlying these issues to inform improvement in agricultural systems. As many of these issues are global in scope, such as the continued maintenance of genetic resources, it is required that we work internationally towards better understanding in ways that also enhance US agriculture.Objective 1: Explore the geographic patterns of molecular and quantitative genetic diversity, plasticity, and local adaptation of landraces of important crops (e.g., maize and chile pepper).Objective 2: Discern how crop diversity responds, and has responded, to historic and current human-mediated and natural selection, including by abiotic conditionsObjective 3: Determine how management of genetic diversity and agroecosystems may affect ecosystem services and resilience to climatic and land use change, using biological and social approaches.
Project Methods
Methods in evolutionary ecology generally involve field experiments and common gardens that allow for the comparison of growth (e.g., germination, morphology, phenology), and physiological function (e.g., photosynthesis, respiration, UV-B protectant compounds), fitness (e.g., survival, seed production), and traits associated ecosystem function (e.g., primary productivity, weed control, root growth and structure) across multiple genotypes and multiple environments. In this way, they also allow for assessment of G x E interactions (i.e., interactions between genetics and environment). Landraces (or traditional varieties) of maize and chile pepper collected from farmers living at different elevations and under different climatic conditions will be planted into common gardens in the field and/or grown under controlled growth chamber and greenhouse conditions. These methods allow us to explore variation in response to environmental conditions, through the morphological, physiological, and fitness traits mentioned above, as well as plasticity and local adaptation. Similar studies can allow us to also quantify the capacity of crop landraces or wild relatives to adapt to new conditions.Phenotypic work can then be paired with molecular analyses to further discern adaptive genetic variation. Using genome sequencing (genotyping-by-sequencing; GBS) and population genetic analysis (e.g., using MANOVA and STRUCTURE) we will clarify population structure. We will probe further to identify genomic regions associated with adaptive traits (e.g., drought tolerance) by using three strategies. First, we will submit sequence data to outlier analyses used to identify regions of the genome that have undergone selection. Second, we will use genome wide association studies (GWAS) in which we associate biogeographic and climatic information with molecular GBS data. Similarly, we will use quantitative trait loci (QTL) analyses to link phenotypic responses to water deficit to molecular GBS data.Studies of the management of diversity for maintaining ecosystem function, even in the face of climate change and land use change, will likely require evaluating accessions for traits of interest (see above), empirical studies of the functions imparted by more and less diverse mixtures, and reciprocal transplant experiments. In addition, social science analysis of the issue may be warranted, using surveys, interviews, or historical/political analysis.