Performing Department
Plant and Soil Sciences
Non Technical Summary
1. The current issue being studied is climate change and its impact on the strategies we now use to develop disease resistant crop varieties. In our project, the crop of interest is wheat. This is important to all sectors of society because we all depend on the availability of a safe, affordable food supply. If we don't develop a strategy to ensure that we can develop disease resistant varieties in a warming environment, our food security will be threatened.2. We intend to simulate warming using heating cables and thermal fabric that covers the wheat plots at night in order to trap radiation and prevent it from going into the environment. Prior to flowering we will inoculate the wheat plants with disease inoculum and then measure disease symptoms and compare them with symptoms in the non heated controls. The results will tell us if the genes that we are currently using will be as effective in a warmed environment.
Animal Health Component
0%
Research Effort Categories
Basic
20%
Applied
80%
Developmental
(N/A)
Goals / Objectives
The overarching goal of the proposed research is to identify and delineate a clear, workablestrategy for selection for resilience to climate change in plant breeding populations.
Project Methods
Project description: 1) There are two types of resistance genes that have been utilized in breeding for FHB resistance: i) exotic QTL such as Fhb1 which can account for a significant proportion of the variation in resistance, and ii) genes of small effect that more closely fit the classic model of quantitative trait inheritance. Both types of genes are effective and widely used, though only the exotic QTL can be tracked with DNA markers; phenotypic selection is required for the latter. The experimental plan is to derive near-isogenic lines (NIL) from the cross 'Pembroke 2014' / 'IL06 - 14262' from F4 plants that are heterozygous at the Fhb1 locus.Pembroke 2014 (tested as KY03C-1237-32) is homozygous for the resistance allele at this locus (http://www.ars.usda.gov/News/docs.htm?docid=19522; verified 19 May 2015) while the Illinois parent carries the susceptible alleles.This will generate pairs of F4:5 NILs derived from the same plant. While not genetically identical they will be nearly identical and thus provide the opportunity to assess the impact of warming on the Fhb1 locus, the most widely used FHB resistance gene. Though IL06-14262 does not carry Fhb1 type resistance, it does have excellent resistance derived from uncharacterized, unmapped loci that are simply referred to as "native resistance genes" by the wheat breeding community. Thus, we can compare the effect of warming on Fhb1 derived resistance with native resistance. These F4:5 lineswillbe grown in microplots - either hill plots or single row "headrow" type plots under control and warmed conditions. Two warming methods will be used: 1) active rhizosphere warming using heating cables and 2) passive night warming of the canopy using thermal fabric shelters.Warming methods that will be used are: active warming with heating cables (buried); thermocouple wires visible. Warming of the rhizosphere is set to 5 degrees C above ambient, which is achieved when the datalogger turns on the heating cables in response to a temperature differential less than 5 C. In the passive warming treatment, thermal fabric on rollers covers the canopy at sunset and automatically retracts at sunrise to trap heat in the canopy between sunset and sunrise.Evaluation of FHB resistance will be carried out using well established published methods that have been used in our project for years. These plots will be inoculated with scabby corn, but not mist irrigated due to the difficulty of imposing both irrigation and warming infrastructure on the same set of plots. Plant height, anthesis date, FHB incidence and severity will be measured. Fusarium damaged kernels (FDK) and mycotoxin levels will be measured in harvested grain using GC-MS methods.2) The second component of this project pertains to my interest in genomic selection. If we are to efficiently utilize the "native" resistance genes, genomic selection is an attractive approach. We will have FHB phenotypic data and can use the major QTL Fhb1 as a fixed effect in the genomic selection model. This will be an excellent population to study the feasibility of using genomic selection for FHB resistance in wheat. However, it is my intention to integrate genomic selection into the breeding program over the course of this proposal. The first step in this process will be to spend time in the lab of a colleague, who is now using genotyping by sequencing (GBS) technology to facilitate genomic selection for breeding projects in the eastern wheat region. We have recently obtained a Roche LightCycler RT-­?PCR instrument that will be suitable for developing KASP markers from the SNP data generated by GBS. These KASP markers can then be used in marker assisted selection.