Rapeseed

About: Rapeseed is a research topic. Over the lifetime, 2945 publications have been published within this topic receiving 51790 citations. The topic is also known as: Brassica napus & rape.

Development of an agronomically superior blackleg resistant canola cultivar in Brassica napus L. using doubled haploidy

Abstract: The doubled haploid breeding method and greenhouse screening using cotyledon bio-assay were successfully applied to transfer blackleg resistance from the Australian cultivar Maluka (Brassicas napus), into susceptible advanced B. napus lines from the University of Alberta. This approach for blackleg resistance breeding was effective and efficient as several superior blackleg resistant breeding lines were identified within 4 yr from the initial cross. One of these lines (91–21864NA) was entered in the 1993 trials of the Western Canada Canola/Rapeseed Recommending Committee. Key words: Blackleg resistance, Leptosphaeria maculans, doubled haploid, Brassica napus

Effect of frost damage on the quality of canola(B. napus)

Abstract: Samples of frost-damaged rapeseed from the 1982 Western Canadian Crop were tested for oil content, protein content, fat acidity, chlorophyll content, fatty acid composition, glucosinolate content, conductivity and germination. These quality factors were related to two frost-related damage factors, green seeds and external “frost-damage,” used in the Canadian grain grading system. The green seed factor was positively correlated with chlorophyll, free fatty acids and conductivity, and a negative correlation was found with linolenic acid, iodine value and germination. The frost-damage factor was positively correlated with conductivity, free fatty acids and palmitic acid and negatively correlated with linolenic acid, iodine value, oil content and germination. The effects of frost damage were explained by assuming that the seed maturation process was halted due to freezing.

Breeding high-stearic oilseed rape ( Brassica napus ) with high- and low-erucic background using optimised promoter-gene constructs

Abstract: Seed lipids of oilseed rape (Brassica napus) usually contain small proportions (<3%) of stearic acid. The objective of this study was to increase the content of stearic fatty␣acid in rapeseed oil. An antisense down-regulation of the endogenous stearoyl-ACP desaturase (SAD) catalysing the reaction step from stearic to oleic acid in two different genetic backgrounds was studied. The result of down-regulation of the SAD yielded an about 10-fold increase of stearic acid from 3.7% up to 32% in single seeds of transgenic low-erucic acid rapeseed (LEAR), while high-erucic acid rapeseed (HEAR) showed a 4-fold increase of C18:0 from 1% up to 4%. It could be shown in pooled T2 seed material of LEAR rapeseed, that the stearic acid content is highly correlated with the down-regulation of SAD as indicated by the␣stearate desaturation proportion (SDP). The importance of the promoter strength for the alteration of a trait was confirmed in this study as no change in the fatty acid composition of transgenic plants was achieved with gene constructs controlled by the weak FatB4 seed-specific promoter from Cuphea lanceolata.

Biological evaluation of hydrogenated rapeseed oil

Abstract: A 91-day feeding study evaluated soybean oil, rapeseed oil, fully hydrogenated soybean oil, fully hydrogenated rapeseed oil, fully hydrogenated superglycerinated soybean oil and fully hydrogenated superglycerinated rapeseed oil at 7.5% of the diet in rats; a 16-wk feeding study evaluated soybean oil and the three rapeseed oils or fats at 15% of the diet. Each fat was fed to 40 rats as a mixture with soybean oil making up 20% of a semi-synthetic diet. No significant differences in body weight gains or diet-related pathology were seen in the 91-day study although the rats fed liquid rapeseed oil had slightly heavier hearts, kidneys and testes than the others. The rats fed the four fully hydrogenated fats ate more feed and had lower feed efficiencies than those fed oils but no differences were seen among the four hydrogenated fats. In the 16-wk feeding study, no pronounced pathology related to the diet was seen although the rats fed liquid rapeseed oil had a slightly higher incidence of histiocytic infiltration of cardiac muscle than the rats in the other groups. The female rats fed the three rapeseed oil fats gained significantly less weight and the females fed liquid rapeseed oil had enlarged hearts compared to the other groups. The absorbabilities of the six fats were measured in the 91-day study when fed as a mixture with soybean oil and as the sole source of dietary fat in a separate 15-day balance study. The four fully hydrogenated fats were poorly absorbed and the absorption of behenic acid from the two hydrogenated rapeseed oils was found to be 12% and 17% in the balance study and 8-40% in the feeding study. The adverse biological effects of unhydrogenated rapeseed oil containing erucic acid as reported in the literature do not occur with fully hydrogenated rapeseed oil. In addition, the low absorbability of the fully hydrogenated rapeseed oil is an added factor in its biological inertness.