Genetics and Genomics Commons^™

Beef Production Systems In The Nebraska Sandhills, Mckay Erickson

Department of Animal Science: Dissertations, Theses, and Student Research

Four studies were conducted to determine the effectiveness of improving production systems of beef cattle in the Sandhills region of Nebraska. These studies were to determine impacts of modified estrus synchronization protocols, genomic testing heifer calves for longevity, and evaluation of 2 differing calving systems (March or May) for improving biological outcome and improved production. Experiment 1 utilized 180 yearling heifers to determine the effectiveness of a second dose of prostaglandin F_2α(PGF) with those females not expressing estrus after an initial 14 d MGA-PG estrus synchronization protocol. The treatment of PGF did increase estrus expression, but did not …

Addressing The Challenges Facing Wheat Production: Nebraska And International Breeding Efforts, Sarah Blecha

Doctor of Plant Health Program: Dissertations and Student Research

Bread wheat, Triticum aestivum L., provides 20 percent of the global daily calorie intake. It is the third most important food crop, after rice and corn. Biotic challenges significantly reduce wheat yield; chemical control can be a solution but can be cost prohibitive for subsistence farmers. For many farmers, genetic resistance to biotic stresses can be the most cost effective solution.

The International Center for Agricultural Research in the Dry Areas (ICARDA) and the Nebraska Small Grains Breeding Program have been addressing these wheat production challenges. ICARDA is part of an international research consortium to increase wheat yield and tolerance …

Genome-Wide Association Studies In Maize And Sorghum, Preston Hurst

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Genome-wide association studies are used to identify genetic variants associated with a particular phenotype. GWAS has been used in a variety of taxa, from humans, to fish to plants . The present analysis is focused on two species important to the human species: maize and sorghum. A GWAS in maize was carried out on the modification of the Ga1-s allele. The Ga1 locus has long been studied as being involved in a unilateral crossing barrier . However, it has long been suspected that the locus is modified by background genetic factors . GWAS was used to observe candidates for this …