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1.
Reducing the high nitrogen (N) balance surpluses occurring in oilseed rape production through the cultivation of N-efficient cultivars is imperative for environmental reasons. In this study, seed yield and N efficiency parameters of oilseed rape cultivars grown under three N rates were investigated in field experiments performed during five years. Seed yields differed significantly among cultivars especially at limiting N supply, with significant shifts in cultivar ranking according to the N level. At high N supply, cultivar differences relied more on year effects. The importance of N efficiency parameters for yield varied owing to year and N rate effects. N uptake was an important parameter for yield at all N rates. While at low N, the duration of N uptake was most decisive, shoot N uptake capacity during vegetative growth was relatively more important under high N conditions. N utilization efficiency became more important with increasing N supply. At high N supply, cultivars with low seed N concentrations were superior in yield. Harvest index was also significantly correlated to yield across N rates; however, its importance depended much on environmental conditions. In conclusion, the specification of plant traits that might contribute to enhanced N efficiency in oilseed rape will depend very much on the N supply of the target environment and the target yield level.  相似文献   

2.
Sclerotinia sclerotiorum is one of the most important pathogens of winter oilseed rape plants. It causes the white mould disease of rape, thus significantly reducing the yield. The aim of our research was to use a spring oilseed rape variety sown in autumn or an early-flowering variety of winter oilseed rape to predict the infection pressure of S. sclerotiorum in a given year. Field experiments were conducted in 2008–2012 at the experimental station of the Czech University of Life Sciences Prague at Červený Újezd, 20 km west of Prague. In the experiment, we used one variety of spring oilseed rape (Lužnice, LU) and one early-flowering variety of winter oilseed rape (Californium, CA). The methodology of the petal test involved isolating pathogenic fungi from fallen petals on a nutrient medium (potato dextrose agar) in Petri dishes. The first term of collection was the beginning of petal fall (BBCH 61) and the last term was the end of flowering (BBCH 69). The dishes with petals were visually analysed after 1 week. The results were compared with the actual occurrence of white mould of rape in the stand. The occurrence of white mould of rape was strongly influenced by the progress of weather conditions over the given year. Infected petals and stems with symptoms of white mould of rape were found to be moderately correlated (r = 0.80). Spread of white mould spores was mostly observed in two terms (BBCH 62 and BBCH 65). Statistically significant differences were not observed in the infection of petals of spring (LU) and winter (CA) oilseed rape. Spring oilseed rape (LU) and early-flowering varieties of winter oilseed rape (CA) can be used to determine the strength of infection pressure of S. sclerotiorum in the stand in a given year, thereby improving protection against white mould of rape.  相似文献   

3.
Sclerotinia sclerotiorum causes serious yield losses in oilseed rape and other crops worldwide. Field trials were conducted at two locations to evaluate two formulations of oilseed rape seed containing the plant-growth promoting bacterium Bacillus megaterium A6 for suppression of this pathogen. Treatments containing strain A6 in pellet and in wrap formulations resulted in oilseed rape seed yields that were similar to the chemical control and significantly greater than the untreated seed control at both locations. Treatments containing A6 in pellet and wrap formulations also resulted in an incidence of disease caused by S. sclerotiorum that was similar to the chemical control. Both of these treatments significantly decreased disease incidence relative to the untreated seed control and to the respective formulated seed controls (that did not contain strain A6) at both locations. Strain A6 applied to oilseed rape seed in these two formulations promoted growth in greenhouse pot studies conducted with autoclaved soil. In two experiments, these treatments resulted in significant increases in mean shoot dry weight per pot and mean % total N per plant relative to their respective controls containing formulated oilseed rape seed without strain A6 and to the untreated seed control. Both formulations provided stable B. megaterium A6 (≥106 CFU) and seed germination (>85%) over a six month period at room temperature. Experiments reported here indicate the commercial potential of these formulations of B. megaterium A6 for suppression of S. sclerotiorum on oilseed rape.  相似文献   

4.
Brassica oilseed yield trend has declined in Finland by over 20% during the last 15 years. Improved genetic yield potential of turnip rape (B. rapa L.) and oilseed rape (B. napus L.) can be better realised with increased understanding of yield determining processes under northernmost growing conditions. This study aimed at (1) determining the genetic improvements in seed yield, yield components, quality traits and duration of the main growth phases and (2) comparing all these traits in turnip rape and oilseed rape. This work is based on the dataset from long-term Official Variety Trials (1976–2006), covering the entire historically relevant period of rapeseed cultivation in Finland. The results indicated that number of seeds per square metre dominated production of high yields, while single seed weight was not correlated with yield. Over the years, seed yields were produced with very different combinations of seed numbers and weights, differing markedly between the two crops. While high seed numbers were required for production of superior seed yields, single seed weights were not particularly high. Environmental variation markedly affected seed yield, seed number per square metre and duration of flowering compared with its effect on single seed weight. Duration of flowering was, however, negatively associated with seed number. Even though seed weight was largely determined by genotype, no marked plant breeding improvements were identified, contrary to those in number of seeds per square metre, seed yield, oil content and oil yield. For oilseed rape the increase in seed yield (41%) was far higher than for turnip rape (19%) without being associated with a longer seed-filling phase and later ripening, but rather the contrary.  相似文献   

5.
氮磷钾肥施用对甘蓝型春油菜产量及肥料利用效率的影响   总被引:6,自引:0,他引:6  
利用大田试验研究了氮、磷、钾肥对青海省互助县种植的甘蓝型春油菜产量、养分吸收量和肥料利用效率等指标的影响。结果表明,氮肥和磷肥对春油菜(甘蓝型杂交油菜青杂2号)籽粒产量的提高有显著作用,钾肥的影响相对较小;与不施肥对照相比,氮、磷、钾肥的施用可显著促进成熟期春油菜地上部N、P、K素累积量(P<0.05);不同肥料的春油菜农学利用率分别为5.3kg/kg N、5.6kg/kg P2O5和1.7kg/kg K2O;肥料表观利用率分别为N 33.6%、P2O5 7.8%和K2O 52.0%, N、P、K肥对油菜籽产量的偏生产力分别为28.0kg/kg N、46.7kg/kg P2O5和26kg/kg K2O。青海省互助县种植条件下,当春油菜产量水平在3 504kg/hm2时,NPK配施条件下每生产100kg籽粒需要吸收N、P2O5、K2O量分别为4.6kg、2.0kg和5.6kg,氮磷钾比为1:0.43:1.21。油菜生产实践中实现高产目标需同时关注地力培肥和平衡施肥两方面。  相似文献   

6.
Increasing interest in vegetable oils for use in green chemistry has stimulated research into high-erucic Brassicaceae species such as winter oilseed rape (Brassica napus L. var. oleifera) and Ethiopian mustard (Brassica carinata A. Braun). The objective of this study was to determine the yield response of recently released cultivars of these species under high and low production inputs. The varieties Maplus and Hearty of B. napus, and BRK1 of B. carinata were cultivated with autumn sowing in a large-scale field trial at the experimental farm of the University of Padova in Legnaro (NE Italy, 45°21′N). The genotypes were compared under high and low input management systems: high input was characterised by conventional soil tillage, chemical weed control, and high N–P–K fertilization, and low input by minimum tillage, mechanical weed control, and limited N–P–K fertilization.Oilseed rape varieties had greater seed yield than BRK1, and interactions with input level and cultivation year were significant. Maplus yielded most at high input (3.78 vs. 3.31 t ha−1 DM at low; average of two years), whereas Hearty showed no significant differences between inputs (3.49 t ha−1; average of years and inputs), indicating its better adaptability to extensive agricultural management. Yield performance of BRK1 B. carinata was very stable at varying agricultural managements, but not very high (2.73 t ha−1 on average) – a fact that may limit its competitiveness with oilseed rape in autumn sowing, especially at higher latitudes. B. carinata was also more variable across the years than oilseed rape in terms of seed yield, oil content, and percentage of erucic acid. This was mainly due to the particular climatic conditions of the second year of the experiment (mild winter; hot, dry spring) which led to considerable winter elongation and pre-flowering, and later to incomplete seed filling. In these conditions, BRK1 had both lower oil seed content (36.7% vs. 47.1%) and erucic acid (41.3% vs. 49.1%) than oilseed rapes.In general, with few exceptions, the reduction in inputs did not affect either seed oil content or the amount of erucic acid, regardless of variety and year, but seed crude proteins were reduced mainly because of N shortage.  相似文献   

7.
Vegetative and reproductive growth information of lesquerella (Physaria fendleri), a new oilseed crop targeted for bio-products, is important to understand especially in the early commercialization stage of this new crop. The objective of this study was to determine the effect of fall, winter, and spring planting dates over three years on the ontogeny of the crop including biomass, floral buds, flowers, and siliques. Fall plantings always produced more than the other plantings due to the extended season. Winter and spring plantings had less biomass and produced fewer buds, flowers, and siliques. The compensation of lower crop management costs and a shorter growing season could make winter a viable option for planting in the southwest. Spring planting could become viable if seed shatter due to summer rains could be reduced. The information will help decide growing regions suitable for crop production and determine what reproductive stages could be manipulated to improve seed yields.  相似文献   

8.
Crop-derived feed protein production is alarmingly low in Europe. Finland represents the northernmost growing region in the world and consequently lacks wide-ranging alternatives to improve crop-based protein production. Spring rapeseed, both turnip rape (Brassica rapa L.) and oilseed rape (Brassica napus L.), are adapted to such northern conditions. This study examines the potential for genotype and environment induced trade-off between oil and protein in rapeseed in order to enhance further the status of rapeseed as a protein crop for northern areas. Datasets on advanced breeding progenies (including cultivars) were provided by Boreal Plant Breeding Ltd., while environment-induced variability in combinations of protein and oil content was studied by using long-term, multi-location datasets of MTT Official Variety Trials. Oilseed rape has more potential as a protein producer than turnip rape, with some 100 kg/ha difference in protein yields. Selecting lines superior in seed protein content at the expense of oil was not a potential means to consolidate protein production capacity per hectare: seed and protein yields were higher the better the capacity of the line to store oil. This can only mean that obviously the lower energy demand for oil synthesis was not alternatively used to boost protein production, but actually vice versa. In the case of environment-induced variation, the highest protein yields were produced in experiments where relatively high protein content was associated with modest oil content, but such conditions were characterised as inefficient in general production capacity and thereby, excessive in applied nitrogen fertiliser. Hence, we were not able to identify promising opportunities for prompt and energy-efficient trade-off between protein and oil in rapeseed.  相似文献   

9.
Understanding the potential for the evolution of herbicide tolerance in weeds following gene flow from transgenic crops is important for their management. The inter-specific hybrids formed between four Brassica juncea populations with different glyphosate-susceptibility and transgenic oilseed rape was studied, emphasizing on the possible population difference. Compared with both parents, the fitness-related components and photosynthetic capacity of hybrids decreased dramatically, but significant differences were observed among different hybrids. All F1 hybrids exhibited highly enhanced but similar herbicide tolerance level regardless of the wild B. juncea parent, indicating that genetically engineered herbicide tolerance may over-dominate phenotype ones by wild-crop hybridization. The analysis of parental loci transmission revealed a higher transfer ratio of male-specific loci detected in F1 hybrids, suggesting that oilseed rape genetic markers can be transferred at relatively high frequencies to the next generation. Therefore, higher transfer ratio of oilseed rape-specific loci, coupled with variation of populations in fitness-related parameters in F1 hybrids, could complicate environmental risk assessment of transgenic oilseed rape, especially in current agroecosystems with increasing application of glyphosate.  相似文献   

10.
Under semiarid Mediterranean conditions irrigated maize has been associated to diffuse nitrate pollution of surface and groundwater. Cover crops grown during winter combined with reduced N fertilization to maize could reduce N leaching risks while maintaining maize productivity. A field experiment was conducted testing two different cover crop planting methods (direct seeding versus seeding after conventional tillage operations) and four different cover crops species (barley, oilseed rape, winter rape, and common vetch), and a control (bare soil). The experiment started in November 2006 after a maize crop fertilized with 300 kg N ha−1 and included two complete cover crop-maize rotations. Maize was fertilized with 300 kg N ha−1 at the control treatment, and this amount was reduced to 250 kg N ha−1 in maize after a cover crop. Direct seeding of the cover crops allowed earlier planting dates than seeding after conventional tillage, producing greater cover crop biomass and N uptake of all species in the first year. In the following year, direct seeding did not increase cover crop biomass due to a poorer plant establishment. Barley produced more biomass than the other species but its N concentration was much lower than in the other cover crops, resulting in higher C:N ratio (>26). Cover crops reduced the N leaching risks as soil N content in spring and at maize harvest was reduced compared to the control treatment. Maize yield was reduced by 4 Mg ha−1 after barley in 2007 and by 1 Mg ha−1 after barley and oilseed rape in 2008. The maize yield reduction was due to an N deficiency caused by insufficient N mineralization from the cover crops due to a high C:N ratio (barley) or low biomass N content (oilseed rape) and/or lack of synchronization with maize N uptake. Indirect chlorophyll measurements in maize leaves were useful to detect N deficiency in maize after cover crops. The use of vetch, winter rape and oilseed rape cover crops combined with a reduced N fertilization to maize was efficient for reducing N leaching risks while maintaining maize productivity. However, the reduction of maize yield after barley makes difficult its use as cover crop.  相似文献   

11.
Flea beetles of the genus Phyllotreta (Coleoptera: Chrysomelidae), which are severe pests in spring oilseed rape, have become increasingly difficult to control in some areas in Sweden. The current practice for plant protection is to use seed treatments followed by foliar applications of insecticide. Seed treatment with the single, currently registered neonicotinoid insecticide (active ingredient: imidacloprid) was compared to untreated controls and seed treatment with clothianidin using Phyllotreta undulata Kutschera beetles from 10 locations. Beetles from the overwintered generation and the new generation from the same 10 locations were used in bioassays to detect possible reduced sensitivity to the pyrethroid lambda-cyhalothrin. Seed treatment with clothianidin provided better protection for seedlings than imidacloprid. Highly variable results were obtained from the pyrethroid bioassays, but tests performed on beetles collected in August indicated that most sampled beetle populations are still susceptible to lambda-cyhalothrin. It is, however, important that the need for foliar applications is minimized to avoid insecticide resistance selection pressure. This requires seed treatments with adequate efficacy against flea beetles together with cultural control measures that can reduce flea beetle damage.  相似文献   

12.
In 2020, diseased seedlings of winter oilseed rape (Brassica napus) with cankered taproots as well as abundant sclerotium-like structures in the soil surrounding the roots were found in Longxi County of Gansu province of northwestern China. A fungus with production of pycnidia was isolated from the diseased roots, and it was identified based on morphological characteristics, molecular phylogeny (ITS, LSU) and PCR detection with the specific primers. The fungus was identified as Leptosphaeria sclerotioides Gruyter, Aveskamp & Verkley [anamorph: Phoma sclerotioides (Preuss) ex Sacc.]. Re-inoculation of isolates of P9 and P10 of L. sclerotioides on winter oilseed rape (B. napus cultivar ‘Zhongshuang No. 9’) in Wuhan caused formation of abundant sclerotium-like structures in soil surrounding the roots, but failed to produce root cankers as those observed in Gansu possibly due to lack of long peroid of low-temperature conditioning in Wuhan. In spite of this, plant height, pod number and seed yield of oilseed rape were significantly reduced in the treatment with L. sclerotioides P9 and P10, compared to the control treatment. To the best of our knowledge, this is the first report of L. sclerotioides on B. napus in China and the finding broadened our understanding about the natural distribution of this psychrophilic fungus.  相似文献   

13.
Seedborne fungi can reduce survival, growth, and yield of maize (Zea mays L.). Laboratory, field, and growth chamber experiments were conducted to determine the effects of the seed treatment fungicides fludioxonil, mefenoxam, and azoxystrobin on germination, plant population, and grain yield of maize grown from low-quality hybrid seed infected with seedborne fungal pathogens. Study I used seed of four hybrids infected at 0-54% incidence with Fusarium spp., Stenocarpella maydis, Penicillium spp., Rhizopus spp., and/or Aspergillus spp. Study II used three seed lots for each of two hybrids infected at 7-37% incidence with S. maydis. Warm and cold germination for untreated seed varied among hybrids in both studies. Warm germination of the seed lot with the highest incidence of S. maydis in study II treated with azoxystrobin and fludioxonil was significantly greater (+7%) than the nontreated control. Plant population in study I was significantly affected by seed treatment, hybrid, and their interactions. Populations were greater (≥9%) for fludioxonil, fludioxonil + mefenoxam, and fludioxonil + mefenoxam + azoxystrobin treatments compared to controls. In growth chamber experiments with pasteurized soil, emergence (≥5%) and plant dry weight (≥14%) were both greater than controls only with the triple seed treatment. Plant populations in study II for all seed treatments except mefenoxam and azoxystrobin alone were greater (≥4%) than controls. Yield in study I was significantly affected by hybrid and seed treatment. Yield for one hybrid was higher (≥20%) than the control with all seed treatments except fludioxonil, whereas yield with another hybrid was consistently greater (≥26%) only with the triple seed treatment. Yield in study II was significantly affected by hybrid, seed treatment, and their interactions. Yield was greater (≥8%) than the controls for all seed treatments with one hybrid and with all (≥5%) except azoxystrobin for the other hybrid. Highest yields occurred with the triple seed treatment. Results indicate that fludioxonil and azoxystrobin can increase germination, population, and yield of maize grown from seed infected by S. maydis and other fungi.  相似文献   

14.
Both crambe (Crambe abyssinicia, Hochst) and rape (Brassica napus L. and Brassica rapus L.) are cool season crops, thus they may have potential as irrigated, winter rotational crops in the low deserts of the southwestern United States and northern Mexico. Currently, no information is available on the effects of fall planting date on the production of these crops. The objectives of this study were (1) to determine the effects of fall planting date on flowering patterns, seed yield, and oil content of crambe and two species of rape, and (2) to determine the suitability of rape and crambe as rotational crops for the low deserts of the southwestern United States. Nine cultivars of rape and one cultivar of crambe were planted at the Maricopa Agricultural Center on three dates in November and December of 1995 and four dates from October through December of 1997 on a variable Mohall sandy loam soil (fine-loamy, mixed hyperthermic, Typic Haplargid). Five of the rape cultivars were B. napus types and the remaining four were B. rapus. One was an industrial rape (R-500) and the other eight were Canola types. Seed yield, oil concentration, and seed weight were determined. In 1996, the percent of plants flowering was observed visually on a periodic basis. In 1998, detailed imaging of flowering was done periodically using a digital camera. Planting date affected water application by controlling the length of the growing season. Our plants were taller, oil content was higher, seed weights were comparable, days to flowering were more than doubled, and seed yields were lower than plants from spring plantings in the Northern Great Plains. In both years of the study, the highest yields were obtained when rape and crambe were planted in November, which would fit well with cotton harvest dates. Lodging was a serious problem in rape. Crambe was sensitive to frost and could fail in some years. Only R-500 matured early enough to be used in rotation with current cotton cultivars. In addition to the onset of flowering, the automated method for estimating flowering was able to detect differences between Brassica species and cultivars and to measure the duration of flowering. Each species had a distinctive flowering pattern. Planting dates also affected the pattern and efficiency of flowering. Reproductive efficiency appeared to change with planting date and in general, October and November planting dates produced seed with higher oil content and seed weights than December planting dates.  相似文献   

15.
在人工接种高病害压条件下,对当前生产上应用的13个油菜双低和杂交品种及14份资源材料进行了 对芜菁花叶病毒( TuMV)的抗性鉴定。结果表明,参试的13个油菜品种均不抗TuMV,但感病性低于对照品种中油 821。14份油菜资源材料间抗性差异显著,有3份材料表现高抗和中抗。大部分油菜推广品种表现的高发病率和 病情指数表明在病害流行地区和年份,这些品种不足以抵挡病毒病造成的损失。  相似文献   

16.
Volunteer potatoes were investigated as infection sources for potato leafroll virus (PLRV) and potato virus X (PVX) in a high elevation seed potato growing area of eastern Idaho. Population densities ofMyzus persicae were assessed. Percentage of PLRV and PVX infection of the volunteers and seed potato crops was determined, as well as density of volunteers and certain parameters of volunteer growth and reproduction. Volunteers apparently harbored no more PLRV than the potato crop from which they originated. But they were found to be an important reservoir of PVX with the infection increasing as much as 12.43% in one year. No aphids capable of transmitting PLRV were found although one species that can transmit potato virus Y was recorded. The mean density of volunteers varied from 0 to 84,880 stems/ha. The number of tubers remaining in the field after harvest and winter weather conditions appeared to be the only factors affecting volunteer density. Volunteer plants arising from seed pieces at an average depth of 6.1 cm were found to set an average of 2.1 new tubers per plant at an average depth of 4.0 cm. These results suggest that volunteer potatoes are a significant source of PVX infection in subsequent seed potato crops.  相似文献   

17.
15%氟啶胺包衣悬浮剂防治油菜根肿病研究   总被引:3,自引:0,他引:3  
为防治油菜重要病害根肿病,研制15%氟啶胺包衣悬浮剂,以甘蓝型油菜品种中双9号为材料的试验结果表明:按包衣比[包衣剂质量(g)∶种子质量(g)]≥1∶50包衣油菜种子,15%氟啶胺包衣剂对种子发芽率、成苗率及油菜苗高、根长和鲜重没有显著影响。用包衣比1∶200、1∶100、1∶50和1∶25包衣的种子,盆栽试验中根肿病的防治效果为43.7%、46.4%、83.5%和92.5%;田间小区试验防治效果分别为22.2%、53.6%、44.5%和54.5%。初步结果说明,可用15%氟啶胺的包衣悬浮剂按包衣比1∶100~1∶50处理种子防治油菜根肿病。  相似文献   

18.
19.
选育高含油量双低油菜品种的理论与实践   总被引:27,自引:1,他引:27  
含油量作为油菜生产最终目标性状产油量的组成因素,与油菜生产效益的提高息息相关。在目前我国 油菜产量水平已得到相当程度提高的前提下,培育高含油量油菜品种是进一步发展油菜产业的必由之路。根据油 菜含油量的遗传特点,结合培育高含油量杂交油菜品种中油杂8号和中油杂11的体会,提出了除了利用黄籽以 外,培育大粒和适宜植株形态性状的品种也是提高油菜含油量的重要途径。初步构建了高含油量油菜品种的形态 组成,并基于近年来参加和通过国家区域试验的冬油菜品种含油量变化情况,展望了我国高含油量油菜育种的发 展前景。  相似文献   

20.
Doubled haploid (DH) production is valuable technology in modern plant breeding of oilseed rape. Doubled haploids can be produced from in vitro isolated and cultured microspores, which, instead of forming pollen, develop into haploid embryos. Either spontaneously or after artificial doubling of chromosomes, the arising resulting plants are diploid and fertile, and 100% homozygous for all genes. Biotechnological DH production offers various advantages for plant breeders, including the possibility to obtain homozygous lines rapidly, as well as easy selection due to the absence of heterozygosity. A DH line with desirable agronomic characters can be chosen and introduced into a breeding program as a result of selection for a combination of optimum characters. The study presents the application of uni- and multi-variate statistical methods to evaluate winter oilseed rape DH lines studied in a series of six experiments repeated at different localities and over a number of years. These methods made it possible to estimate individual DH lines under various environmental conditions, including the assessment of the content and stability of two different fatty acid compositions. The aim of the study was to classify and select the best oilseed rape genotypes with regard to the requirements of chemical and biodiesel industry concerning fatty acid compositions at simultaneously high seed yield. The paper contains the results of statistical analysis of 37 genotypes (32 DH lines, 2 parental forms, F2 and F3 hybrids and standard cultivar) performed on the basis of experiments carried out at 6 environments. A total of 14 genotypes were found satisfactory (11 stable and 3 unstable) for the chemical industry and 10 genotypes satisfactory (6 stable and 4 unstable) for the biodiesel industry. Among them 5 genotypes had very profitable significant and positive estimates of the main effect for seed yield.  相似文献   

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