Thesis (Ph. D.)--Washington State University, May 2006. / Includes bibliographical references.

Thesis (Ph. D.)--Colorado State University, 2004. / Includes bibliographical references.

Thesis (M.S.)--Oregon State University, 2011. / Printout. Includes bibliographical references (leaves 66-72). Also available on the World Wide Web.

LD2668 .T4 1940 M33 / Master of Science

Graduation date: 1991

Thesis (M. Sc.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on Jan. 26, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Agricultural and Resource Economics, Department of Rural Economy, University of Alberta. Includes bibliographical references.

Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 149-168). Also available on the World Wide Web.

Thesis (M.Sc.)--University of Alberta, 2009. / Title from pdf file main screen (viewed on August 28, 2009). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of master of science in Agricultural and Resource Economics, Rural Economy Department. Includes bibliographical references.

No description available.

A higher level of efficiency in the production of doubled-haploids must be achieved if this procedure is to be beneficial in plant improvement. Of equal importance is the development of protocols, which are not genotypic specific and result in progeny that represent a random sample of gametes from the parental lines. To address these issues seven diverse winter wheat genotypes and a spring wheat, previously shown to be responsive in haploid plant production from anther culture, represented the experimental material. Two methods of generating haploid plants were employed. These were anther culture and the intergeneric hybridization of wheat with maize. Three induction media (MN6, P2 and Liang's) in liquid and semi-solid forms were employed with anther culture a direct culture. A modified floret culture along with different concentrations (20 and 100 ppm) and mode of application of 2,4-D were examined for the wheat x maize approach, Measurements included callus and embryo production and haploid plantlet regeneration. Two winter genotypes 'Gene' and 'Yamhill' did not respond to the anther culture methodology. For responsive genotypes MN6 was superior to P2 and Liang's medium for the traits measured. In contrast 'Chris' the spring wheat was more responsive for plantlet regeneration on P2 medium. No differences in haploid plantlet regeneration for the traits were observed between liquid and semi-solid medium forms. For the wheat x maize approach, direct culture was superior to the modified floret culture for embryo and haploid plantlet production. No differences were found in either 2,4-D concentration or whether 2,4-D was applied through tiller injection or placed as droplets on the florets. The wheat x maize approach was superior to anther culture for both embryo and green haploid plant production based on the number of florets used. Albino plants were produced in all responsive genotypes with anther culture. In contrast, no albino plants were regenerated with the wheat x maize approach. All genotypes were responsive for both embryo production and haploid plant regeneration in the intercrossing approach. In addition no regeneration distortion was observed for specific population employing this protocol. The wheat x maize approach was superior to anther culture for embryo production. This was also true for green haploid production based on the number of florets used. A higher proportion of albino plants was also observed when anther culture was employed. A further attribute of the wheat x maize approach was that all genotypes tested were responsive to embryo and haploid production. It was also revealed that no segregation distortion was present in three doubled haploid populations developed from wheat x maize crosses. / Graduation date: 1999