Inheritance and molecular markers for high oleic and low linolenic acids in canola (Brassica napus) and impact of genotype and environment on these traits
Pure doubled haploid (DH) plants were developed from two new high oleic and low linolenic (HOLL) canola varieties (NPZ, Germany our Industry partner). A number of reciprocal crosses were made between selected lines and a DH line of commercial variety (Monty-028DH) (ex CBWA Pty Ltd). Four reciprocal crosses were selected and F1 plants were used to produce 1200 haploid plantlets. Seed harvested from fertile DH plants were used as the base DH populations to study the genetic segregation of fatty acid in each cross. About 400 lines were grown at Manjimup Hort. Res. Inst. during summer 2004-05 for seed increase and leaf samples were taken for molecular work. Different primers for FAD2, FAD3, FAD6 and FAD7 fatty acid genes were developed. These primers were used to amplify and sequence parents. On the basis of polymorphism found in parents, CAPS markers were developed and are being used on the population.
1. Specialty canola oil (HOLL) is in demand from the oil industry and there is a competition from other oil seed crops as well.
2. Molecular markers will help to increase the speed of breeding new HOLL varieties adapted to Australian conditions.
3. QTL analysis will be used to locate the candidate gene(s) for fatty acid metabolism, if the candidate gene approach fails.
4. In breeding, only minimal quantities of seed for fatty acid analysis are available at the first harvest: therefore it is crucial for DH and transgenic population/breeding to be able to test just one or a few seeds for FA profile.