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.

Effects of saturated fat in rats fed rapeseed oil.

Abstract: The effects of increasing the saturated fatty acids in a dietary vegetable oil composed mostly of unsaturated fatty acids were studied in rats. A mixture of palm oil and Swedish rapeseed oil fed fo...

Academic and Economic Importance of Brassica napus Rapeseed

Abstract: Rapeseed or canola (B. napus) is the second most important oilseed crop of the world. It is also a favourite plant for basic and breeding research. Due to its origin and evolution, rapeseed has a complex polyploid genome. Recent sequencing of the corresponding genomes provides the basis for a better understanding and exploitation of the genetic diversity involved in major rapeseed traits. However, directed selection for major quality characteristics, i.e. minimal erucic acid content and low glucosinolate level, has caused genetic bottlenecks limiting genetic variation in the current gene pools of cultivated oilseed rape (OSR). Therefore, broadening genetic diversity is an important aim of research and a necessary prerequisite for further progress by OSR breeding. In agricultural production, rapeseed is nowadays an indispensable component of crop rotations in major growing areas such as Australia, Western Canada, Central China and many countries of the European Union. In many cases, OSR is the only leaf crop among dominating cereal species. Therefore, OSR as a component of crop rotations helps to maintain soil fertility and contributes to sustainable production therefore. As a major cash crop OSR substantially contributes to farmers’ incomes and therefore helps to stabilize rural populations. Beyond that, as major globally traded agricultural commodities rapeseed/canola and rapeseed/canola oil and meal significantly input the national products of a number of countries e.g. Canada. Rapeseed/canola is a raw material for vegetable oil and extraction meal as feed, food and fuel. The oil is mainly used as a high-value salad oil for dressings etc. due to its high contents of oleic acid (ca. 60%) and poly-unsaturated linolenic acid (omega-3, ca. 10%). Nevertheless, a large part is also used as a mobility fuel for diesel cars and tractors, particularly in Germany and Europe. The extraction meal (and protein) from oil processing is now recognized as a highly valuable animal feed, particularly for ruminants (cattle) but also for monogastric farm animals (pigs, poultry). Furthermore, the interest in rapeseed protein for the purpose of human nutrition is increasing. Optimal contents of the major compounds mentioned before represent the main requirements for rapeseed/canola varieties today. Consequently, quality characteristics are major criteria for variety testing and registration therefore. Other major requirements for modern rapeseed varieties are yield and various agronomic traits securing seed yield, i.e. resistance against fungal diseases and insect pests. Because of the environmental concerns and the rejection of agrochemicals such as insecticides (e.g. ban of neonicotinoids in the EU), genetic approaches of establishing resistant crop cultivars constantly gain importance. OSR breeding has long been a relatively ordinary process of repeated selection for resistance, quality and yield, the propagation of improved populations and their release as new open pollinated (OP) varieties. Since this approach is not very effective, breeders have been interested in breeding hybrids instead. Today, F1 hybrids represent the major variety type. They are produced with genetic male sterility systems, most of which are based on cytoplasmic mutations causing male sterility (cms). The higher performance of hybrids is caused by “heterotic effect” which largely depends on the genetic distance between the parents. Therefore, distant genetic pools need to be generated for the development of female and male parents. The future potential of variety design is consequently determined by the usefulness of the genetic pools and the performance of hybrid parents extracted from them. Modern breeding tools based on biotechnology and genomics can substantially contribute to a better exploitation of useful genetic diversity, i.e. specific genes and genetic networks. Better varieties are a precondition for further crop improvement. Future quality OSR cultivars deserve high yield potential, combined with good stability due to disease and pest resistance. This will be the basis for exploiting the great agronomical and industrial advantages of the rapeseed plant.

QTL for phytosterol and sinapate ester content in Brassica napus L. collocate with the two erucic acid genes

Abstract: Improving oil and protein quality for food and feed purposes is an important goal in rapeseed (Brassica napus L.) breeding programs. Rapeseed contains phytosterols, used to enrich food products, and sinapate esters, which are limiting the utilization of rapeseed proteins in the feed industry. Increasing the phytosterol content of oil and lowering sinapate ester content of meal could increase the value of the oilseed rape crop. The objective of the present study was to identify quantitative trait loci (QTL) for phytosterol and sinapate ester content in a winter rapeseed population of 148 doubled haploid lines, previously found to have a large variation for these two traits. This population also segregated for the two erucic acid genes. A close negative correlation was found between erucic acid and phytosterol content (Spearman’s rank correlation, rs = −0.80**). For total phytosterol content, three QTL were detected, explaining 60% of the genetic variance. The two QTL with the strongest additive effects were mapped on linkage groups N8 and N13 within the confidence intervals of the two erucic acid genes. For sinapate ester content four QTL were detected, explaining 53% of the genetic variance. Again, a close negative correlation was found between erucic acid and sinapate ester content (rs = −0.66**) and the QTL with the strongest additive effects mapped on linkage groups N8 and N13 within the confidence intervals of the two erucic acid genes. The results suggests, that there is a pleiotropic effect of the two erucic acid genes on phytosterol and sinapate ester content; the effect of the alleles for low erucic acid content is to increase phytosterol and sinapate ester content. Possible reasons for this are discussed based on known biosynthetic pathways.

Honey bee foraging in spring oilseed rape crops under high ambient temperature conditions

Abstract: Honey bee foraging activity on the flowers of two spring rapeseed varieties ‘SW Savann’ and ‘Ural’ was evaluated. High air temperature throughout the study period allowed us to investigate the interaction between plants and their pollinators under weather conditions unusual for Lithuania. Analysis of flowering intensity and honey bee density in the two rape varieties showed that ‘Ural’ produced on average 4.6% more flowers than ‘SW Savann’, however, honey bee density in ‘Ural’ plots was about 4% lower than that in ‘SW Savann’ plots. A decrease in flowering intensity was followed by a decrease in honey bee density in both rape varieties. A strong increase in ambient temperature had a negative impact on the foraging of honey bees on flowering plants. The lowest honey bee density in the investigated rape plots was recorded in the afternoon, when air temperature reached +43°C. High ambient temperature affected oilseed rape flowering and pollinator density on flowers and this could have had a negative effect on seed yield of oilseed rape.

Digestibility by growing pigs of amino acids in canola meal from North America and 00-rapeseed meal and 00-rapeseed expellers from Europe.

Abstract: The digestibility of CP and AA by growing pigs in coproducts from canola and 00-rapeseed may be influenced by the variety of seeds that was grown and the processing method used to extract the oil from the seeds. Therefore, the objective of this experiment was to determine the apparent ileal digestibility (AID) and the standardized ileal digestibility (SID) of CP and AA in canola meal, 00-rapeseed meal, and 00-rapeseed expellers fed to growing pigs. Canola meal and 00-rapeseed meal are the coproducts produced after the residual oil has been solvent extracted from canola seeds and 00-rapeseeds, respectively, whereas 00-rapeseed expellers is the coproduct from 00-rapeseeds that have been only expeller pressed. Twenty-three barrows (initial BW: 28.8 ± 2.64 kg) that had a T-cannula installed in the distal ileum were allotted to a 9 × 23 Youden square design with 9 periods and 23 dietary treatments. The 23 diets included 7 diets based on the 7 samples of canola meal, 10 diets based on the 10 samples of 00-rapeseed meal, 5 diets based on the 5 samples of 00-rapeseed expellers, and a N-free diet. Each source of canola or rapeseed coproducts was used as the only source of CP and AA in 1 diet. The SID of CP and all AA except Val, Cys, and Glu were not different between canola meal and 00-rapeseed meal, but 00-rapeseed expellers had greater (P < 0.01) SID of CP and all AA except Thr, Trp, and Gly than 00-rapeseed meal, which possibly is due to heat damage in 00-rapeseed meal. For Lys, Met, Thr, and Trp, SID values of 70.6%, 84.5%, 73.0%, and 82.6%, and 71.9%, 84.6%, 72.6%, and 82.6% were obtained in canola meal and rapeseed meal, respectively, whereas values in 00-rapeseed expellers were 74.7%, 87.1%, 74.0%, and 83.4%. The SID for most AA was different (P < 0.05) among the 7 sources of canola meal, among the 10 sources of 00-rapeseed meal, and among the 5 sources of 00-rapeseed expellers. The concentration of standardized ileal digestible indispensable AA in canola and 00-rapeseed coproducts can be predicted from the concentration of the corresponding AA with only a low to moderate correlation (r(2) = 0.206 to 0.655). In conclusion, AA digestibility is not different between canola meal and 00-rapeseed meal, but 00-rapeseed expellers have greater digestibility of most AA than 00-rapeseed meal. Prediction equations may not always adequately estimate the concentration of indispensable AA and standardized ileal digestible indispensable AA in canola and 00-rapeseed coproducts.