Renewed interest in Camelina sativa is primarily due to the unique fatty acid profile of the seed oil and its potential value in industry, cosmetics and human nutrition. To exploit C. sativa in western Canada, more information is needed on the performance of this crop in this region. Following a preliminary evaluation in 2001, replicated agronomic trials were conducted in 2002 and 2005 with 19 C. sativa and three oilseed Brassica accessions at Saskatoon and Scott, Saskatchewan and Beaverlodge, Alberta. The C. sativa accessions matured relatively early and were more tolerant of drought and flea beetle infestations than the Brassica oilseeds. Some C. sativa accessions had seed yields competitive with those of the Brassica oilseeds, but seed size was significantly smaller. Seed yields and oil contents of all crop species tested were highest at Beaverlodge, the most northern location. The Brassica oilseeds generally had higher oil contents than C. sativa; the highest oil contents of each crop species tested were associated with the lowest protein contents. In general, average oil and protein contents for C. sativa ranged from 38 to 43% and from 27 to 32%, respectively; for the Brassica checks, oil and protein contents ranged from 38 to 53% and from 21 to 33%, respectively, across all species. Variation in fatty acid composition was higher among the C. sativa accessions than among locations, but overall the ranges of individual fatty acids were relatively narrow. The most abundant fatty acids were oleic (12.8–14.7%), linoleic (16.3–17.2%), linolenic (36.2–39.4%) and eicosenoic (14.0–15.5%). The prospects of developing improved C. sativa germplasm for particular western Canadian environments are good; of primary importance are increased seed size and oil content. Additionally, stand establishment, fertility requirements and broadleaf weed control options need to be investigated. Acceptance of this species as a new oilseed crop for western Canada will also require developing sustainable markets for the oil and meal. Key words: Camelina sativa, seed quality, agronomic trait, oil and protein content, fatty acid
Information on genetic diversity and genetic relationships among genotypes of Brassica carinata is currently limited. The objectives of this study were to evaluate patterns and levels of genetic diversity in B. carinata based on amplified fragment length polymorphisms (AFLP) as compared with Brassica juncea and Brassica nigra, and to evaluate agronomic and seed quality data for plants grown in the field in western Canada. A total of 296 AFLP bands were generated from four primer pair combinations and scored for presence/ absence in 66, 20 and 7 accessions of B. carinata, B. juncea and B. nigra, respectively. B. carinata was less genetically diverse than the other two species. Differences in diversity were evident in the proportion of polymorphic loci within each species: 23, 35 and 50% for B. carinata, B. nigra and B. juncea, respectively. Pair-wise similarity measures based on the Jaccard coefficient were highest among accessions of B. carinata and showed the narrowest range: 0.911 (0.810-0.981) compared to B. nigra: 0.569 (0.438-0.660) and B. juncea: 0.715 (0.345-0.951). AFLP-based genetic distance information can be used by plant breeders to select diverse genotypes. AFLPs are also useful for fingerprinting cultivars and two primer pair combinations were sufficient to uniquely identify all the accessions of B. carinata. More variation among accessions was identified in the agronomic trial than had previously been described in studies of B. carinata in western Canada, but the data were too limited to draw conclusions regarding specific accessions. Overall, the findings were in agreement with other published work describing the favourable agronomic potential of this species.
Blackleg, caused by Leptosphaeria maculans, is one of the most economically important diseases of Brassica napus worldwide. Two blackleg-resistant lines, 16S and 61446, were developed through interspecific hybridization between B. napus and B. rapa subsp. sylvestris and backcrossing to B. napus. Classical genetic analysis demonstrated that a single recessive gene in both lines conferred resistance to L. maculans and that the resistance alleles were allelic. Using BC(1) progeny derived from each resistant plant, this locus was mapped to B. napus linkage group N6 and was flanked by microsatellite markers sN2189b and sORH72a in an interval of about 10 cM, in a region equivalent to about 6 Mb of B. rapa DNA sequence. This new resistance gene locus was designated as LepR4. The two lines were evaluated for resistance to a wide range of L. maculans isolates using cotyledon inoculation tests under controlled environment conditions, and for stem canker resistance in blackleg field nurseries. Results indicated that line 16S, carrying LepR4a, was highly resistant to all isolates tested on cotyledons and had a high level of stem canker resistance under field conditions. Line 61446, carrying LepR4b, was only resistant to some of the isolates tested on cotyledons and was weakly resistant to stem canker under field conditions.
We report the tagging of genes involved in blackleg resistance, present in the French cultivar Crésor of B. napus, with RFLP markers. A total of 218 cDNA probes were tested on the parental cultivars Crésor (resistant) and Westar (susceptible), and 141 polymorphic markers were used in a segregating population composed of 98 doubled-haploid lines (DH). A genetic map from this cross was constructed with 175 RFLP markers and allowed us to scan for specific chromosomal associations between response to blackleg infection and RFLP markers. Canola residues infested with virulent strains of Leptosphaeria maculans were used as inoculum and a suspension of pycnidiospores from cultures of L. maculans, including the highly virulent isolate Leroy, was sprayed to increase disease pressure. QTL mapping suggested that a single chromosomal region was responsible for resistance in each of the four environments tested. This QTL accounted for a high proportion of the variation of blackleg reaction in each of the assays. A second QTL, responsible for a small proportion of the variation of blackleg reaction, was present in one of four year-site assays. A Mendelian approach, using blackleg disease ratings for classifying DH lines as resistant or susceptible, also allowed us to map resistance in the region of the highly significant LOD scores observed in each environment by interval mapping. Results strongly support the presence of a single major gene, named LmFr 1 controlling adult plant resistance to blackleg in spring oil-seed rape cultivar Crésor. Several RFLP markers were found associated with LmFr 1.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.