Performing Department
(N/A)
Non Technical Summary
Oat is a healthful cereal crop that is widely grown for food and use in consumer skin care products. The health-promoting properties of oats are due to many different compounds, including avenanthramides, antioxidants found almost exclusively in oats. In addition to contributing to consumer well-being, avenanthramides also serve an important role in oat production because they are implicated in reducing severity of plant disease outbreaks. Avenanthramides are thus important, multi-functional compounds in oats. However, avenanthramide concentrations are highly variable across environments, creating a challenge for plant breeders to reliably increase concentration and for growers to predictably harvest high avenanthramide oats. This project addresses that challenge by developing new plant breeding and management strategies to fine-tune oat avenanthramide production. Specifically, this project will test how purposely activating plant immune responses - the changes in expression of genes and biochemical pathways in response to a biological stress - can lead to more consistent avenanthramide production in order to to improve oat nutritional quality and disease resistance. This project will evaluate how avenanthramide biosynthesis changes in response to immune activation using genome sequence, gene expression, and biochemical pathway analysis. Importantly, oats will also be evaluated under field conditions of high disease pressure and across multiple geographic locations to pinpoint factors that contribute to avenanthramide variability and the degree to which variability may be mitigated by immune activation. Overall, the goal of this project is to improve oat performance (disease resistance) and grain nutritional quality (antioxidants) through enhancing avenanthramide levels. Improving consistency and output of avenanthramides benefits oat growers, processors and consumers by expanding oat cultivationand increasing access to health-promoting oat varieties. Finally, targeting avenanthramides and immune responses in plant breeding is an innovative approach to breeding for disease resistance, and will serve as a template for similar efforts in other crops.
Animal Health Component
30%
Research Effort Categories
Basic
70%
Applied
30%
Developmental
(N/A)
Goals / Objectives
Oat (Avena sativa L.) seeds contain a suite of health-promoting compounds, some of which also contribute to plant disease resistance. It is beneficial to oat growers, processors and consumers to improve consistency and output of these compoundslike avenanthramides, antixoidants found in oat seeds and other tissues. The goal of this project is thus to investigate how oat genetic variation and management practices can be leveraged to increase seed avenanthramidesby triggering plant immune responses, and testing how both avenanthramides and immune activation can reduce severity of multiple diseases. This project will encompass pre-breeding efforts that incorporate quantitative genetics and phenomics to improve oat nutrition and plant disease resistance.The objectives of this project are to:Characterize variation in constitutive oat seed avenanthramides, and avenanthramides induced upon activating plant immune responses at the genomic, transcriptomic and metabolomic levels.Test the degree to which activated plant immune responses reduce severity of multiple diseases (crown rust, Fusarium head blight, barley yellow dwarf virus and loose smut), and how infection and treatment interact to affect avenanthramide concentration.Assess genotype-by-environment variance in avenanthramides to identify and characterize environments in which treatment may be most productive.
Project Methods
Objective 1.Characterize variation in oat seed avenanthramides when immune responses are triggered, at the genomic, transcriptomic and metabolomic level?s.We will measure oat seed avenanthramides that are constitutively present and also avenanthramides that areinduced by application of a salicylic acid analog, an immune activation treatment. These phenotypes will be measured in diverse oat germplasm that are representative of North American spring oats. We hypothesize that avenanthramide concentration will increase with treatment, but the magnitude of change will be genotype-dependent. We will then conduct a genome-wide association studies (GWAS) and identify a subset of the germplasm with contrasting constitutive and induced avenanthramide concentrations for more intensive analysis. Specifically, in this subset of germplasm, we will characterize avenanthramideaccumulation, the full metabolome profile and gene expression during seed development to key identify genes and regulatory pathways underlying variation in seed avenanthramide biosynthesis and in response to treatment.Objective 2.Test the degree to which activated plant immune responses reduceseverity of multiple diseases, and interact with avenanthramides.We will test the degree to which plant immune activation reduces the severity of oat crown rust, Fusarium head blight, barley yellow dwarf virus and loose smut. Disease severity will be evaluated in the field in dedicated disease nurseries that promote the spread of the individual disease over two field seasons. We predict that, because many of these diseases demonstrate salicylic acid mediated resistance, treatment with a salicylic acid analog will be efficacious in a disease-dependent manner. We will also assess changes in avenanthramide concentration, as well as metabolome-wide shifts to elucidate the interactive effect of treatment and pathogen infection. Although avenanthramides often increase during infection, we predict that treatment will moderate further induction by disease, resulting in more consistent avenanthramide production.Objective 3.Assess genotype-by-environment variance in avenanthramides to identify and characterize environments in which immune activation may be most productive.To promote incorporation of immune activation treatments and responsive germplasm into oat management, we will conduct multi-year multi-location field trials to ascertain the degree of genotype-by-environment (GxE) interaction in avenanthramide variation, and characterize the contribution of environmental factors. Specifically, we will analyze avenanthramide content in a set of elite and experimental spring oat varieties grown in multiple environments over two years in the upper Midwest to (1) estimate the heritability, (2) quantify environment and GxE variance, and (3) identify environmental factors influencing avenanthramidecontent. We hypothesize that GxE will be highest in locations with high pathogen pressure. We will also evaluate how treatment affects avenanthramides and other agronomic and quality traits in field trials, and predict that treatment will reduce GxE. Specifically, this will complementthe larger GxE experiment by evaluating avenanthramides with and withouttreatment in yield nurseries (not disease nurseries) in a subset of locations. Together, these results will provide information for on-farm application of this research, including which environments and conditions benefit most from treatment in optimizing avenanthramide levels.