Showing papers on "Rapeseed published in 2008"

In-depth investigation of the soybean seed-filling proteome and comparison with a parallel study of rapeseed.

Abstract: To better understand the metabolic processes of seed filling in soybean (Glycine max), two complementary proteomic approaches, two-dimensional gel electrophoresis (2-DGE) and semicontinuous multidimensional protein identification technology (Sec-MudPIT) coupled with liquid chromatography-mass spectrometry, were employed to analyze whole seed proteins at five developmental stages. 2-DGE and Sec-MudPIT analyses collectively identified 478 nonredundant proteins with only 70 proteins common to both datasets. 2-DGE data revealed that 38% of identified proteins were represented by multiple 2-DGE species. Identified proteins belonged to 13 (2-DGE) and 15 (Sec-MudPIT) functional classes. Proteins involved in metabolism, protein destination and storage, and energy were highly represented, collectively accounting for 61.1% (2-DGE) and 42.2% (Sec-MudPIT) of total identified proteins. Membrane proteins, based upon transmembrane predictions, were 3-fold more prominent in Sec-MudPIT than 2-DGE. Data were integrated into an existing soybean proteome database (www.oilseedproteomics.missouri.edu). The integrated quantitative soybean database was compared to a parallel study of rapeseed (Brassica napus) to further understand the regulation of intermediary metabolism in protein-rich versus oil-rich seeds. Comparative analyses revealed (1) up to 3-fold higher expression of fatty acid biosynthetic proteins during seed filling in rapeseed compared to soybean; and (2) approximately a 48% higher number of protein species and a net 80% higher protein abundance for carbon assimilatory and glycolytic pathways leading to fatty acid synthesis in rapeseed versus soybean. Increased expression of glycolytic and fatty acid biosynthetic proteins in rapeseed compared to soybean suggests that a possible mechanistic basis for higher oil in rapeseed involves the concerted commitment of hexoses to glycolysis and eventual de novo fatty acid synthesis pathways.

Regulation of growth, fatty acid composition and delta 6 desaturase expression by dietary lipids in gilthead seabream larvae (Sparus aurata)

Abstract: The Δ6 and Δ5 desaturases and elongases show only very limited activity in marine fish, and little is known of the possibility of enhancing Δ6 desaturase gene expression in these fish. The use of plant oils in marine fish diets is limited by their lack of n−3 highly unsaturated fatty acids (HUFA) despite an abundant content of the 18C fatty acid precursor linoleic and α-linolenic acids. The objective of the present study was to determine the ability of larval gilthead seabream to utilize vegetable oils and assess the nutritional regulation of Δ6 desaturase gene expression. Seventeen-day-old gilthead seabream larvae were fed during a 17-day period with one of four different microdiets formulated with either sardine fish oil (FO), soybean, rapeseed or linseed oils, respectively, or a fifth diet containing defatted squid meal and linseed oil. Good larval survival and growth, both in terms of total length and body weight, were obtained by feeding the larvae either rapeseed, soybean or linseed oils. The presence of vegetable oils in the diet increased the levels of 20:2n−9 and 20:2n−6, 18:2n−9, 18:3n−6, 20:3n−6 and 20:4n−6, in larvae fed rapeseed and soybean oils in comparison to those fed FO. In addition, a sixfold increase in the relative expression of Δ6 desaturase-like gene was found in larvae fed rapeseed and soybean oils, denoting the nutritional regulation of desaturase activity through its gene expression in this fish species. However, feeding linseed oil did not increase the expression of the Δ6 desaturase gene to such a high extent.

Anti-Nutritional Components, Fibre, Sinapine and Glucosinolate Content, in Australian Canola ( Brassica napus L.) Meal

Abstract: Canola meal is highly regarded as a component of animal feed with a high protein content and a desirable amino acid profile. The presence of some components, in particular glucosinolates, sinapine and fibre, affects the value of the meal and reduces the amount that can be used in animal feed formulations. Glucosinolates in traditional cultivars (rapeseed) had very high amounts and this severely limited the usefulness of the meal. Canola breeding programs have successfully reduced glucosinolate content to trace amounts. However sinapine remains at levels sufficiently high to cause problems, particularly in poultry feed. The relatively high fibre level in canola also reduces the value of the product for animal feed. This study has determined the level of sinapine, glucosinolates and fibre in current cultivars of canola in Australia to illustrate advances made by breeding programs and limitations which still remain to raise the usefulness of a potentially valuable feedstock. Although glucosinolate levels in meal were shown to have been reduced to 11 μmol/g in some cases, sinapine remained at traditional levels of about 12–15 g/kg and neutral detergent fibre levels were about 30–40%. These issues are important priorities for canola breeders.

Zero erucic acid trait of rapeseed ( Brassica napus L.) results from a deletion of four base pairs in the fatty acid elongase 1 gene

Abstract: The fatty acid elongase 1 (FAE1) gene is a key gene in the erucic acid biosynthesis in rapeseed. The complete coding sequences of the FAE1 gene were isolated separately from eight high and zero erucic acid rapeseed cultivars (Brassica napus L.). A four base pair deletion between T1366 and G1369 in the FAE1 gene was found in a number of the cultivars, which leads to a frameshift mutation and a premature stop of the translation after the 466th amino acid residue. This deletion was predominantly found in the C-genome and rarely in the A-genome of B. napus. Expression of the gene isoforms with the four base pair deletion in a yeast system generated truncated proteins with no enzymatic activity and could not produce very long chain fatty acids as the control with an intact FAE1 gene did in yeast cells. In the developing rape seeds the FAE1 gene isoforms with the four base pair deletion were transcribed normally but failed to translate proteins to form a functional complex. The four base pair deletion proved to be a mutation responsible for the low erucic acid trait in rapeseed and independent from the point mutation reported by Han et al. (Plant Mol Biol 46:229–239, 2001).

Effects of α-Tocopherol on Oxidative Stability and Phytosterol Oxidation During Heating in Some Regular and High-Oleic Vegetable Oils

Abstract: The first part of this study evaluated oxidative stability in high-oleic rapeseed oil, palm olein, refined olive oil, low erucic acid rapeseed oil and sunflower oil. The results showed oxidative stability in the order: palm olein > high-oleic rapeseed oil > refined olive oil > low erucic acid rapeseed oil > sunflower oil, as determined by the Rancimat method. Addition of α-tocopherol at high levels of up to 0.2% increased the oxidative stability of refined olive oil, whereas the opposite effect was generally observed in the other oil samples. In the second part of the study, high-oleic rapeseed oil, palm olein, refined olive oil and refined olive oil containing 0.2% α-tocopherol were heated for 3, 6, 9 and 12 h at 180 °C. The peroxide and p-anisidine values generally increased over time in the samples, including olive oil containing 0.2% α-tocopherol. High-oleic rapeseed oil contained the highest amount of total sterols and total phytosterol oxidation products (POPs), but during heating the total POPs content increased moderately (~10%), in contrast to the threefold increase after 12 h of heating in palm olein and refined olive oil. Very high levels of 6-hydroxy derivatives of brassicastanol, campestanol and sitostanol and of 7-ketobrassicasterol were observed in high-oleic rapeseed oil samples. Addition of 0.2% α-tocopherol during heating significantly decreased POPs formation in refined olive oil (P < 0.05).

Graphic Analysis of Trait Relations of Rapeseed Using the Biplot Method

Abstract: Interest in growing winter rapeseed (Brassica napus L.) in Iran is increasing due to its potential returns relative to other oilseed crops. The objectives of this study were (i) to investigate the interrelationships among different traits ofwinter rapeseed and (ii) to determine the effects ofsowing date and variety on the seed yield and other traits ofwinter rapeseed with application of the biplot methodology in visualizing agronomic research data. Four winter rapeseed varieties were grown on three sowing dates during 2 yr. The results showed that variety 1 (SLM046) produced maximum seed yield and oil content in the second (21 September) and the third sowing dates (1 October). Thousand seed weight was positively and significantly associated with seed yield and the number of pods per plant, but oil content was not correlated with yield or the other traits. The study revealed that treatment by trait (TT) biplot can graphically display the interrelationships among traits and facilitate visual comparison of treatments.

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.

The Correlation and Path Analysis of Yield and Yield Components of Different Winter Rapeseed (Brassica napus ssp. oleifera L.) Cultivars

Abstract: This research was conducted in Ankara conditions during 1999-2000 and 2000-01 using 25 winter oilseed rape cultivars. The experiment was carried out in randomized complete block design with 3 replications. The aim of the study was to determine the correlation and path coefficient analyses among some characters and the direct and indirect effect of these characters on seed and oil yield in winter rapeseed. Correlation analysis results showed a high, positive and statistically significant (P < 0.01) statistically correlation between branches per plant, the number of pods on the main stem and plant height during both years. Plant height indicated negative correlation with seed yield, 1000-seed weight, and oil ratio during the first year of the trial. Based on a comparison of the effects of seed and oil yield on different yield components, it was observed that seed yield directly affected oil contents directly. Comparing the indirect effects on oil yield, interactions with other yield components of seed yield had the greatest effect, and except for oil ratio, the indirect effect of all characters was higher during the first year. An increased plant height affected rise in branching adversely, which increased lodging resulting in reduced seed yield.

Why is it so difficult to produce high‐quality virgin rapeseed oil for human consumption?

Abstract: Virgin rapeseed oil becomes increasingly popular for the consumer because of the pleasant seed-like and nutty taste and smell. The oils are produced in small and medium-sized facilities by extraction of rapeseed using only a screw press and purifying the oil by sedimentation or filtration. Thus, the producers have no chance to improve the oil quality if the seed quality is bad. Therefore, it is an art to produce high-quality virgin rapeseed oil that is accepted by the consumer. The most important step in the production chain of virgin rapeseed oil is the period after harvest until the processing, while extraction of the oilseed and purification has only a minor influence on the oil quality. The paper describes the pitfalls during the production of virgin rapeseed oil which primarily wait for the producer during storage of the seeds. Improper storage conditions result in increased metabolic processes in the seeds and an increase of the populations of microorganisms and insects, which finally leads to the degradation of nutrients and the formation of unpleasant aroma compounds.

Fatty Acid Composition, Tocopherols and Beta-Carotene Content in Polish Commercial Vegetable Oils

Abstract: The fatty acid composition, tocopherols and β-carotene content in the following vegetable oils: rapeseed, olive, arachide, sunflower, soybean, corn, grapeseed, pumpkin seed, sesame and linseed were evaluated. The study comprised commercial refined and cold pressed oils from different manufacturers. The fatty acid composition was determined by Gas Chromatography (GC) method on a 50m capillary column with a CP Sil 88 phase. α-, β-, γ-, δ-tocopherols and β-carotene contents were analyzed by HPLC method with a Lichrospher Si 60 column. The study showed that β-carotene was present only in some cold pressed oils. The amount of tocopherols varied much between oil types and between the same type of oil from different producers. Among all tested oils, sunflower oil had the highest vitamin E content. The rapeseed oil, the most popular on Polish market was characterized by the highest content of α-linolenic acid and the lowest 18:2/18:3 ratio. The α-tocopherol equivalent to polyenoic content ratio was the highest in olive oil and the lowest in commercial linseed oil. Only 1.6% of linolenic acid in the total fatty acid composition was observed in the linseed oil.

Genetic Variation and Genotype × Environment Interactions of Phytosterol Content in Three Doubled Haploid Populations of Winter Rapeseed

Abstract: Phytosterols are natural constituents of vegetable oils and are known for their cholesterol-lowering properties. The oil of rapeseed (Brassica napus L.) is one of the richest natural sources of phytosterols. Genetically enhancing the phytosterol content could give an added value to the rapeseed oil and derived products. Our objectives were to develop a gas-liquid chromatographic method for the analysis of phytosterol content in seeds of oilseed rape, to determine the genetic variation and the genotype x environment interactions, and to estimate correlations between phytosterols and other important seed quality traits in three doubled haploid populations of winter rapeseed. The populations were tested during several years in three to four environments. Sitosterol and campesterol were detected as the two major phytosterols followed by brassicasterol, avenasterol, and stigmasterol. Large differences were found in total phytosterol content (2.57 to 4.15 g kg -1 seed), with predominant genetic variance components resulting in high heritabilities ranging from 0.84 to 0.91. Phytosterol content was not negatively correlated with oil content and there were no close correlations to protein and glucosino-late content. The large genetic variation along with high heritabilities indicate that an effective breeding for enhanced phytosterol content and modified composition should be possible without negative impacts on oil, protein, or glucosinolate content.

A study of the growth of Pseudallescheria boydii isolates from sewage sludge and clinical sources on tributyrin, rapeseed oil, biodiesel oil and diesel oil.

Abstract: The study compared the growth of Pseudallescheria boydii isolates from sew- age sludge and from clinical sources on tributyrin, rapeseed oil, biodiesel oil and diesel oil agars. The isolates grew on all substrates tested. The highest growth was observed on rapeseed oil agar, while the lowest on diesel agar. On tributyrin agar, hydrolysis zones were observed around or underneath the colonies. On rapeseed oil agar, no hydrolysis zones were formed, while most isolates formed such a zone on biodiesel oil agar. Rape- seed oil and biodiesel oil stimulated the growth of P. boydii isolates, while tributyrin inhibited fungal growth. The stimulation or inhibition effect of diesel oil was dependent on the specifi ed strain. In clinical isolates, fungal growth and activity were found to be more variable compared to sludge isolates. The data suggest that contamination of the environment with these oils could favor the growth of P. boydii. However, no association was found between the growth and oil utilization by this fungus and its pathogenicity.

Gene expression profiles associated with intersubgenomic heterosis in Brassica napus

Abstract: In order to understand the genetic mechanism of heterosis that has been observed in hybrids between Brassica napus and partial new-type B. napus which had exotic genome components from relative species, this study focused on the difference in gene expression patterns among partial new-typed B. napus lines, B. napus cultivars and their hybrids using the cDNA amplified fragment length polymorphism technique (cDNA-AFLP) technique. First, three partial new-type B. napus lines were compared with their original parents. One new line contained the exotic genomic components from B. rapa, and the other two new lines were obtained by the introgression of genomic components from B. rapa and B. carinata. The experimental results showed that the introgression of Ar and Cc genome components from B. rapa and B. carinata led to considerable differences in the gene expression profiles of the partial new-type lines when compared with their parents. Secondly, the gene expression profiles of nine cross-combinations between three partial new-type lines and three B. napus cultivars were compared. Twenty transcript-derived fragments (TDFs) associated with intersubgenomic heterosis were randomly selected and converted into PCR-based molecular markers. Some of them were mapped in the confidence intervals of quantitative trait loci (QTLs) for yield and yield-related traits in three segregative populations of B. napus. These results suggested that a proportion of the heterosis-associated TDFs were really responsible for fluctuating seed yield in rapeseed.

Are there indications of climate change induced increases in variability of major field crops in the northernmost European conditions

Abstract: As the northern hemisphere will experience the greatest increases in temperature and indications of climatic change are already visible in the north (in the 2000s average temperatures exceeded the long-term mean), we sought to establish if there are already signs of increased variability in yield and quality of the major field crops grown under the northernmost European growing conditions: spring and winter cereals (barley Hordeum vulgare L., oat Avena sativa L., wheat Triticum aestivum L., rye Secale cereale L.), spring rapeseed (turnip rape Brassica rapa L., oilseed rape B. napus L.), pea (Pisum sativum L.) and potato (Solanum tuberosum L.). We used long-term yield datasets of FAO for Finland (1960s to date) and MTT Agrifood Research Finland (MTT) Official Variety Trial datasets on yield and quality of major field crops in Finland since the 1970s. Yield variability was exceptionally high in the 1980s and 1990s, but previously and subsequently national yields were clearly more stable. No progressive increase in yield variability was recorded. No marked and systematic changes in variability of quality traits were recorded, except for rapeseed, which exhibited reduced variability in seed chlorophyll content. This may at least partly attribute to the differences in intensity of input use and thereby responsiveness of the crops before and after 1980 and 1990 decades. We also noted that in the 2000s average temperatures were higher than in earlier decades and this was the case for all months of the growing season except June, which represents, however, the most critical phase for yield determination in most of the field crops in Finland. Also in the 2000s precipitation increased in the first three months of the growing season and thereafter decreased, but without signs of significantly increased numbers of heavy showers (extreme rain events). Hence, in general constant, increased average temperatures during the growing seasons of the 2000s were identified, but with reduced yield variability, which was partly attributable to the diminished use of inputs, especially fertilisers.

Effects of compost and green manure of pea and their combinations with chicken manure and rapeseed oil residue on soil fertility and nutrient uptake in wheat-rice cropping system

Abstract: Farmers use huge chemical fertilizers for cereal production, which causes health and environmental hazards. Adoption of legumes in cereal based cropping systems and improvement of organic fertilizers are needed to reduce chemical fertilizer use. Pot experiments were carried out with compost and green manure of pea plant residue with dried chicken manure and/or rapeseed oil residue to find out effects of compost and green manure on soil fertility and nutrient uptake by wheat and rice. Pea residue was mixed with chicken manure or rapeseed oil residue or half of chicken manure plus rapeseed residue or nothing was mixed for composting and green manuring for wheat. We also examined the residual effects of the fertilizers on rice. Composts of pea residue with chicken manure and chicken manure plus rapeseed residue enriched soil with N, P, K and other nutrients, and increased nutrient accumulation. Higher values were found for compost than for green manure but green manure with rapeseed residue also supplied higher residual nutrients and improved uptake and yield components. Rapeseed residue released nutrients slowly but chicken manure was efficient and stimulated the former when they were mixed. Pea compost with chicken manure or chicken manure plus rapeseed oil residue is recommended to improve soil fertility for wheat and rice.

The phytotoxic effects and biodegradability of stored rapeseed oil and rapeseed oil methyl ester

Abstract: The aims of this study were to determine the phytotoxicity of stored rapeseed (Brassica rapa) oil (RSO) and rapeseed oil methyl ester (RME) after “spill like” contamination on the growth of barley (Hordeum vulgare) and the biodegradability of these substances in OECD 301F test conditions and in ground water. Rapeseed oil and rapeseed oil methyl ester were both stored for a period of time and their fuel characteristics (e.g. acid number) had changed from those set by the fuel standards and are considered to have an effect on its biodegradation. The phytotoxicity was tested using two different types of barley cultivars: ‘Saana’ and ‘Vilde’. The phytotoxic effect on the barley varieties was determined, after the growth season, by measuring the total biomass growth and the mass of 1000 kernels taken from the tests plots. Also visual inspection was used to determine what the effects on the barley growth were. These measurements suggest that both RSO and RME have a negative impact on barley sprouts and therefore the total growth of the barley. RSO and RME both decreased the total amount of harvested phytomass. The weight of 1000 kernels increased with low concentrations of these contaminants and high contamination levels reduced the mass of the kernels. The results of these experiments suggest that the stored rapeseed oil and rapeseed oil methyl ester are both phytotoxic materials and therefore will cause substantial loss of vegetation in the case of a fuel spill. The RSO and RME biodegraded effectively in the measurement period of 28 days under OECD test conditions: the degree of biodegradation being over 60%. The biodegradation in the ground water was much slower: the degree of biodegradation being about 10% after 28 days.

Rapeseed And Mustard

Abstract: Rapeseed (Brassica campestris) and Mustard (Brassica juncea) are the major rabi oilseed crops of India. India is one of the largest producer of these crops in the world. The production of rapeseed and mustard in India accounts for about 18% of the total oilseed production of the country. Sarson and toria (lahi) are generally termed as rapeseed, rai or raya or laha is termed as mustard. The seed and oil are used as condiment in the preparation of pickles and for flavouring curries and vegetables. The oil is utilized for human consumption throughout northern India in cooking and frying purposes. The oil cake is used as a cattle feed and manure. Green stems and leaves are a good source of green fodder for cattle. The leaves of young plants are used as green vegetables as they supply enough sulphur and minerals in the diet.

Inheritance of long chain fatty acid content in rapeseed ( Brassica napus L.)

Abstract: A large industrial oil market has recently developed for high erucic acid (>500 g kg−1) rape (Brassica napus L.) cultivars. This research was conducted to: (i) determine genetic effects for five fatty acids, (ii) determine if maternal effects influence fatty acid content of progeny, and (iii) estimate correlations among fatty acid contents in hybrid progeny. Lines with very high erucic acid content and very low erucic acid content were used to develop eight generations to estimate additive, dominance, and epistatic effects for fatty acid content using Generation Means Analyses. Mean oleic, linoleic, linolenic, eicosenoic and erucic acid content differed among generations and additive genetic effects were important for control of all five fatty acids, contributing from 84% to 97% of the total sums of squares for each fatty acid. Epistasis was observed in the inheritance of eicosenoic acid. Maternal effects were not detected.

The effect of nitrogen fertilization on tocopherols in rapeseed genotypes

Abstract: Tocopherols (α-, β-, γ- and δ-tocopherol) are naturally occuring antioxidants in vegetable oils. In rapeseed oil, α- and γ-tocopherols are the predominant isomers, while δ-tocopherol contributes much lower amounts to the total tocopherol content. Enhanced tocopherol content in seeds appears favourable, and breeding for tocopherol content has become an increasingly important objective in winter oilseed rape. The main objectives of this research were to quantify the amount of tocopherols in a number of rapeseed varieties and to investigate the effect of nitrogen fertilization on tocopherol concentration in the seed. The field trials were carried out in 2004–2005 and 2005–2006 at Dardanos, Canakkale on the Turkish West Coast (10 km south of the city centre) with 13 varieties, three replications and three nitrogen levels (N0: 0 kg/ha, N1: 130 kg/ha and N2: 260 kg/ha). The trial used a randomized complete block design with 6 m2 plots. Tocopherol analysis was done using an HPLC system. Significant differences were found among the varieties and between the nitrogen levels. The average total tocopherol concentration was 118.7 mg kg−1 for N1, 134.1 mg kg−1 for N2 and 133.6 mg kg−1 for N3 fertilization level. MDS analysis indicated a rough grouping of line versus hybrid varieties and suggested that hybrids require more breeding effort to reach the level of tocopherols existed in line varieties.

Cultivar improvement and environmental variability in yield removed nitrogen of spring cereals and rapeseed in northern growing conditions according to a long-term dataset

Abstract: The balance between applied and harvested nitrogen (yield removed nitrogen, YRN %) is a recognized indicator of the risk of N leaching. In this study we monitored the genetic improvements and environmental variability as well as differences among crop species (spring cereals and rapeseed) in YRN in order to characterize changes that have occurred and environmental constraints associated with reducing N leaching into the environment. MTT long-term multi-location field experiments for spring cereals ( Hordeum vulgare L., Avena sativa L. and Triticum aestivum L.), turnip rape (Brassica rapa L.), and oilseed rape (B. napus L.) were conducted in 1988–2008, covering each crop’s main production regions. Yield (kg ha -1 ) was recorded and grain/seed nitrogen content (N grain , g kg -1 ) analyzed. Total yield N (N yield , kg ha -1 ) was determined and YRN (%) was calculated as a ratio between applied and harvested N. A mixed model was used to separate genetic and environmental effects. Year and location had marked effects on YRN and N yield . Average early and/or late season precipitation was often most advantageous for N yield in cereals, while in dry seasons N uptake is likely restricted and in rainy seasons N leaching is often severe. Elevated temperatures during early and/or late growth phases had more consistent, negative impacts on YRN and/or N yield for all crops, except oilseed rape. In addition to substantial variability caused by the environment, it was evident that genetic improvements in YRN have taken place. Hence, YRN can be improved by cultivar selection and through favouring crops with high YRN such as oat in crop rotations.

Development of a SCAR Marker to Track Canola Resistance Against Blackleg Caused by Leptosphaeria maculans Pathogenicity Group 3

Abstract: Blackleg of rapeseed and canola (Brassica napus) is caused by various pathogenicity groups (PG) of Leptosphaeria maculans. The disease occurring in the Canadian prairies for the last two decades was caused by PG2 and was controlled by host resistance. PG3 and PG4 isolates have been found recently in Canada, but there is no resistance available against these pathogenicity groups in commercial Canadian varieties. This study sought to identify canola cultivars that could be used as sources of resistance to PG3 and to develop molecular markers for marker-assisted selection. Resistance to PG3 specifically was found in B. napus 'Dunkeld' and 'Quinta', while B. juncea 'Cutlass' and 'Domo' proved to be resistant to PG2, PG3, and PG4. A set of F2 progeny of 'Westar' (susceptible) × 'Dunkeld' was used to identify genetic markers linked to PG3 resistance. These markers were physically located on a BAC clone from B. rapa subsp. pekinensis containing a homolog to a serine threonine 20 (ste20)-like kinase in Arabidopsis thaliana. Thus, we have developed a sequence characterized amplified region (SCAR) marker available for marker-assisted selection in breeding canola for resistance against blackleg caused by L. maculans PG3. This work has received a provisional patent (serial # 60/977,933 - Oct. 5, 2007).

Chromosomal stability and performance of resynthesized Brassica napus produced for gain in earliness and short‐day response

Abstract: Brassica napus (AACC) was resynthesized by sexual hybridization between the two diploid progenitors, B. campestris (AA) and B. oleracea (CC), represented by short-day adapted accessions selected from a larger collection brought together. The aim to produce a photoperiod insensitive, artificial rapeseed possible to grow during the dry winter season in Bangladesh proved successful. A plant breeding programme adjusting more general features is started. Preliminary results are reported, proving the superior seed yield structure of napus but at the cost of a prolonged period between flowering and maturity. With the aim to evaluate the most convenient approach for the resynthesis, four different methods were applied in combining campestris (always as mother) and oleracea: Method A (2x × 2x), Method B (2x × 2x, followed by colchicine treatment), Method C (4x × 2x) and Method D (4x × 4x). Irrespective of method applied, the euploid AACC (B. napus) constitution proved to have a very high selective advantage. Even hybrids from Method A and C with the constitution AC (2n=19), AAC (2n=29) or ACC (2n=28) had a clear tendency to produce balanced AACC types. This trend was considerably strengthened and followed up by improved pollen- as well as seed fertility, if the primary hybrids were crossed with a natural B. napus. Method D gave the highest frequency of balanced AACC offsprings, but it is questionable whether the extra work to produce 4x progenitors really pays economically.

Effect of honeybees pollination on seed setting, yield and quality characteristics of rapeseed (Brassica napus oleifera)

Abstract: The study was conducted during 2004-06 to determine the effects of pollination using honeybees on seed yield and quality characteristics of the rapeseed 'Pulsar' winter variety of canola (Brassica napus ssp. oleifera) was grown and small colonies of honeybee (Apis mellifera anatoliaca) were placed in mini hives with or without pollen trap. The present study contained 4 pollination treatments, viz. T 1 , an open field; T 2 , a cage without bees, T 3 , a cage with bees in a regular mini hive and T 4 a cage with bees mini hive with pollen trap. Seed yield was 3 205, 1823, 2 360 and 2 357 kg/ ha for the treatments T 1 , T 2 , T 3 and T 4 respectively. The differences in pods/plant, seeds/pod and seed yield/plant were found significant (p<0.05) and highest values were obtained from open field, followed by a cage with bees in a regular mini hives and a cage with bees in a bottom pollen trap hive. Seed weight, branches/plant, harvest index, seed protein and oil content were insignificantly influenced by treatments. Honeybee pollination increased the seed yield significantly but not protein and oil percentage in seeds.

Screening and comparing tocopherols in the rapeseed (Brassica napus L.) and olive (Olea europaea L.) varieties using high-performance liquid chromatography

Abstract: Rapeseed and virgin olive oils are a good source of tocopherols. Tocopherols are the most important compounds having antioxidant activity in both crops. Little is known about the tocopherol contents of rapeseed and olive oil grown in Turkey. The aims of this research were to investigate some new rapeseed varieties and olive genotypes grown in northwest Turkey and to compare the tocopherol fractions and contents of both crops. For rapeseed, the data were collected in two growing seasons (2004-2005, 2005-2006) from a field experiment with 19 new rapeseed varieties. For olives, virgin olive oils produced from 21 different varieties were examined in the 2004-2005 and 2005-2006 growing seasons. The separation and identification of tocopherols and the analysis of their contents were successfully achieved using the high-performance liquid chromatographic method. According to the obtained results, gamma-tocopherol (44.200-118.900 mg/kg) was the major fraction of total tocopherol, followed by alpha-tocopherol (19.300-68.500 mg/kg) and delta-tocopherol (0.00-2.600 mg/kg) for rapeseeds. Regarding olive varieties, the alpha-tocopherol content changed between 52.000 and 194.750 mg/kg, followed by gamma-tocopherol ranging from 0.00 to 39.750 mg/kg. The total tocopherol content ranged between 83.900 and 173.800 mg/kg for rapeseed and between 52.100 and 213.075 mg/kg for olives. This study revealed that an important variability exists for tocopherol content and composition in rapeseed and olive varieties.