The control of seed oil polyunsaturate content in the polyploid crop speciesBrassica napus.
Many important plant species have polyploidy in their recent ancestry, complicating inferences about the genetic basis of trait variation. Although the principal locus controlling the proportion of polyunsaturated fatty acids (PUFAs) in seeds ofArabidopsis thalianais known (fatty acid desaturase2;FAD2), commercial cultivars of a related crop, oilseed rape (Brassica napus), with very low PUFA content have yet to be developed. We showed that a cultivar of oilseed rape with lower than usual PUFA content has non-functional alleles at three of the four orthologousFAD2loci. To explore the genetic basis further, we developed an ethyl methanesulphonate mutagenised population, JBnaCAB_E, and used it to identify lines that also carried mutations in the remaining functional copy. This confirmed the hypothesised basis of variation, resulting in an allelic series of mutant lines showing a spectrum of PUFA contents of seed oil. Several lines had PUFA content of ~6 % and oleic acid content of ~84 %, achieving a long-standing industry objective: very high oleic, very low PUFA rapeseed without the use of genetic modification technology. The population contains a high rate of mutations and represents an important resource for research inB. napus.
John Innes Centre, Norwich Research Park, Norwich, NR4 7UH UK.
Rachel
R
Wells
John Innes Centre, Norwich Research Park, Norwich, NR4 7UH UK.
Martin
M
Trick
John Innes Centre, Norwich Research Park, Norwich, NR4 7UH UK.
Eleni
E
Soumpourou
John Innes Centre, Norwich Research Park, Norwich, NR4 7UH UK ; The Genome Analysis Centre, Norwich Research Park, Norwich, NR4 7UH UK.
Leah
L
Clissold
John Innes Centre, Norwich Research Park, Norwich, NR4 7UH UK.
Colin
C
Morgan
KWS UK Ltd., 56 Church Street, Thriplow, Hertfordshire, SG8 7RE UK.
Peter
P
Werner
KWS UK Ltd., 56 Church Street, Thriplow, Hertfordshire, SG8 7RE UK.
Carl
C
Gibbard
Monsanto UK Ltd., PO Box 663, Cambridge, CB1 0LD UK.
Matthew
M
Clarke
Saaten-Union UK Ltd., Rosalie Field Station, Bradley Road, Cowlinge, Newmarket, Suffolk, CB8 9HU UK.
Richard
R
Jennaway
John Innes Centre, Norwich Research Park, Norwich, NR4 7UH UK ; Department of Biology, University of York, Heslington, York, YO41 5DD UK.
Ian
I
Bancroft
Brassica; Desaturation; EMS; Fatty acid biosynthesis; Oleic acid; Polyunsaturated fatty acids