Broadening of genetic diversity in spring canola (Brassica napus L.) by use of the C-genome of Brassica oleracea var. alboglabra and B. oleracea var. botrytis

• Author / Creator

  IFTIKHAR, RAMEEZ

• Spring oilseed Brassica napus L. (AACC, 2n = 38) canola is one of the most important crop in Canada, widely grown in the Prairie Provinces Alberta, Manitoba and Saskatchewan. Presence of genetic diversity in breeding material is pre-requisite for developing new cultivars with desirable traits as well as for progress in breeding. The narrow genetic diversity in spring B. napus canola can be broadened by enriching its C-genome with the C-genome of progenitor species Brassica oleracea L. The present research was undertaken to study the feasibility of introgressing allelic diversity from B. oleracea var. alboglabra and B. oleracea var. botrytis into Canadian spring B. napus canola for the improvement of this crop. For this, Brassica napus × B. oleracea interspecific crosses were made and the F1’s were either self-pollinated for F2 or backcrossed to the B. napus parent for BC1 seeds. The F2- and BC1-derived populations were subjected to self-pollination with selection in each generation for different agronomic and seed quality traits including erucic acid and glucosinolate contents from where F8 and BC1F7 families were developed. The interspecific cross derived plants were analysed by a flow cytometer to estimate their approximate chromosome number; while the extent of genetic diversity introgressed from B. oleracea into these plants was assessed by the use of simple sequence repeat (SSR) markers.
  
  Plant fertility was low in early generation populations. However, inbreeding with selection for fertile plants resulted in B. napus plants in advanced generation populations. Silique size and number of seeds per silique in many of the advanced generation plants was comparable to the B. napus parent.
  
  Segregation for erucic acid and glucosinolate contents in the populations derived from this interspecific cross involved only the C-genome alleles; this enabled efficient selection of canola quality plants from both F2- and BC1-derived populations. Molecular marker analysis showed that the plants derived from both F2 and BC1 are genetically distinct from the B. napus parent; this demonstrated the feasibility of introgressing allelic diversity from B. oleracea var. alboglabra and B. oleracea var. botrytis into spring B. napus canola.

• Subjects / Keywords

  • Genetic diversity
  • Brassica napus
  • spring canola
  • Brassica oleracea

• Graduation date

  Fall 2015

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R34M91J7P

• 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.