Off-campus UNL users: To download campus access dissertations, please use the following link to log into our proxy server with your NU ID and password. When you are done browsing please remember to return to this page and log out.
Non-UNL users: Please talk to your librarian about requesting this dissertation through interlibrary loan.
Rapid Cycling in Spring Wheat: Genetics and Use in Converting Winter Wheat for Rapid Cycling
Backcrossing winter wheat (Triticum aestivum L.), due to vernalization, takes 4–5 years. Rapid cycling of spring wheat reduces generation times, thus expediting backcrossing. In this study, a spring wheat ‘Apogee’ was crossed to winter wheats ‘Goodstreak’, ‘Overland’, and ‘NW07505’ to understand and transfer rapid cycling genes. Our aims were to 1) study rapid cycling genes in segregating populations of Overland × Apogee, NW07505 × Apogee, and Goodstreak × Apogee; 2) evaluate allelic variation and effects of rapid cycling genes Vrn-A1, Ppd-D1, Rht-B1 and Rht-D1 on flowering date and plant height in the F5 of Goodstreak × Apogee and in the BC1F1 of Goodstreak//Goodstreak/Apogee; 3) develop rapid cycling recurrent parent (RCRP) of the three winter wheat lines; 4) determine which generation of selfing population is better for creating RCRP; 5) verify phenotypic data with molecular markers to identify rapid cycling lines. ^ Segregation analysis revealed that not less than three or four rapid cycling genes segregated in winter x spring crosses. The effect of Vrn-A1 was greater than the other loci on flowering in the F 5 and BC1F1 populations. The F5 progenies that contained Apogee genotype flowered earlier and was shorter than Goodstreak and epistasis between Rht-B1b/Rht-D1b was the major effect on reducing plant height in the F5 population. These results indicated that rapid cycling progeny can be used for reducing generation time in backcross breeding. Supplementing molecular markers with phenotypic data can be used to understand the effect of rapid cycling genes and assist selection for the earliest flowering lines.^
Boontung, Rungravee, "Rapid Cycling in Spring Wheat: Genetics and Use in Converting Winter Wheat for Rapid Cycling" (2017). ETD collection for University of Nebraska - Lincoln. AAI10608760.