Broadening of genetic diversity in spring canola (Brassica napus L.) by use of the C genome of Brassica oleracea var. italica and Brassica oleracea var. capitata

  • Author / Creator
  • Spring canola Brassica napus L. (AACC, 2n = 38) is one of the major crops in Canada. A decline in genetic diversity in breeding populations is a threat for continued improvement of this crop from a long-term perspective. Genetic diversity in Canadian spring B. napus canola can be broadened through introgression of allelic diversity from its diploid progenitor species Brassica rapa L., Brassica oleracea L., and other allied species of the family Brassicaceae. This M.Sc. thesis research investigated the feasibility of introgression of new alleles from two variants of B. oleracea, viz. B. oleracea var. italica (broccoli) and var. capitata (cabbage) into spring B. napus canola. For this, B. napus × B. oleracea interspecific crosses were made and the F1 plants were self-pollinated for F2 seeds as well as backcrossed to the B. napus parent for backcross (BC1) seeds. The F2 and BC1 populations were self-pollinated for several generations with selection for canola quality traits for the development of euploid B. napus (2n = 38) plants. Plant fertility was poor in early generations; however, it improved with the progression of generation. Flow cytometric analysis for nuclear DNA content showed that the majority of the advanced generation plants were similar to the B. napus parent. Segregation for erucic acid and glucosinolate contents was found in all populations where selection for zero erucic acid and low glucosinolate content led to the development of canola quality lines in advanced generation. Estimation of genetic diversity in F4 and BC1F3 populations by the use of simple sequence repeats (SSR) markers showed that B. oleracea alleles introgressed in the progeny derived from B. napus × B. oleracea crosses. Thus, the results from this study demonstrated the viability of introducing alleles from broccoli and cabbage into spring B. napus canola.

  • Subjects / Keywords
  • Graduation date
    Spring 2016
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.