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Development of biofortified winter wheat by incorporating low phytate and high grain protein traits

Jorge Patricio Venegas, University of Nebraska - Lincoln

Abstract

Common wheat (Triticum aestivum L.) represents an important source of nutrients for humans. Unfortunately, some minerals are not fully digestible due to the presence of antinutrients such as phytic acid in the wheat kernel. The objectives of this study were to incorporate low phytate (LPA) and high grain protein traits into Great Plains adapted wheats to determine: 1) the effect of lpa1-1 (low phytate) and Gpc-B1 (high protein) alleles in increasing grain total and dialyzed minerals; 2) the effect of allelic combination on grain yield and quality traits; 3) the heredity of the lpa1-1 allele and its location in the wheat genome; and 4) the feasibility of releasing LPA winter wheat germplasm with good agronomic and quality characteristics. The lpa1-1 and Gpc-B1 combination did not lower yield, grain protein concentration, or total grain Fe and Zn concentrations. The lpa1-1 allele alone and in combination with the Gpc-B1 allele increased dialyzed Zn, Ca and Mn. A negative correlation between grain yield and some quality traits was found in this and previous studies. Despite this, the combination of the lpa1-1 and Gpc-B1 allele could be exploited to increase mineral bioaccessibility without reducing grain yield. Inheritance of lpa1-1, as inferred from assay of inorganic phosphate (Pi) best fit a model of two recessive alleles with an epistatic interaction. After linkage and QTL mapping, two major QTLs were identified for the Pi trait that explained 15.78% and 27.33% of the phenotypic variation. Six Kompetitive allele-specific PCR (KASP) markers were designed and they can be used in breeding efforts to reduce phytate in wheat. Ten Great Plains adapted LPA lines were selected for agronomic, quality and rust resistance characteristics. Grain yields of some of the LPA lines were significantly higher than grain yields of some of the control materials. There were no significant differences in yield, grain volume weight, and protein between the LPA lines and the adapted controls. The LPA lines had 35% more grain total iron and 18% more grain total zinc concentration than the adapted controls. These lines are the first winter wheat LPA germplasm to be released in the United States.

Subject Area

Genetics|Plant sciences|Bioinformatics

Recommended Citation

Venegas, Jorge Patricio, "Development of biofortified winter wheat by incorporating low phytate and high grain protein traits" (2017). ETD collection for University of Nebraska-Lincoln. AAI10682150.
https://digitalcommons.unl.edu/dissertations/AAI10682150

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