James Anderson, Professor
Department of Agronomy and Plant Genetics
Sponsor: Forever Green Initiative, Clean Water Fund
Award Amount: $63,700
The perennial grain intermediate wheatgrass (IWG) shows great potential to be developed as a crop for food use, and provides sustainable environmental benefits. In past and current projects we found all IWG breeding populations that we analyzed to have higher fiber and protein contents, yet different protein profiles than wheat. Milling and starch damage data collected indicated that IWG kernels have soft endosperms. Differences in endosperm texture affect the properties of the flour. In wheat, hardness is strongly controlled by the lipid binding Puroindoline proteins that are produced by two tightly linked Pin genes at the Ha locus on chromosome 5DS. Common wheat has variation in the Pin genes that result in hard wheat (e.g. hard red spring wheat).
Our examination of near-isogenic wheat lines differing in Pin alleles and containing hard or soft endosperm revealed effects on protein content and gluten protein profile. The hard wheat with knocked-out Pin genes had higher protein content and higher glutenin to gliadin ratio than its counterpart. Current IWG germplasm is deficient in glutenins, the proteins responsible for dough strength and elasticity, and are high in gliadins. Producing IWG with hard endosperm may result in enhanced protein profile and hence functionality. DNA sequence analysis indicates a close homoeology between wheat Pin genes and those in IWG, so our hypothesis is that non-functional Pin alleles conferring harder endosperm may already exist in IWG or could be developed by induced mutation and/or crossing or selfing of germplasm encoding for specific non-functional Pin allele variants.
We will develop primer sequences based on Pin genes in IWG and screen collections of germplasm and induced mutation populations to identify alleles with predicted changes in protein sequence that would result in hard endosperm. Simultaneously, we will phenotype a subset of 50 genets from the breeding program to examine existing differences in endosperm hardness and protein profile. Germplasm with non-functional or knockout alleles at Pin loci will be further developed and screened for their hardness and protein profile.