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排序方式: 共有113条查询结果,搜索用时 31 毫秒
1.
在浙江省杭嘉湖平原区区域农业环境地球化学调查的基础上,选择嘉善县西塘、余杭县乔司二个典型地区作为专题研究区,对比研究了土壤条件与油菜元素含量、生长及产量间的关系,指出制约油菜生长的土壤地球化学因素,为研究区以至区域内油菜生产的种植和合理施肥提供了科学依据。  相似文献   
2.
This study was carried out to compare the kinetic accumulation of bioactive lipids during seed development in three oil crops rapeseed, sunflower and woad. Field experiments were conducted under organic conditions during 3 years. After flowering, seeds were collected each 4–5 days until harvest. The three species differed by the quantity and quality of both fatty acids and sterols. Higher levels of phytosterols and fatty acids were reached between 20 and 40 days after flowering (DAF) in sunflower, 40 and 60 DAF in rapeseed and 25 and 45 DAF for woad. The modification of lipid composition during the grain filling depends on species. Knowledge of the composition and accumulation of fatty acids and phytosterols in sunflower, rapeseed and woad seeds would assist in efforts to achieve industrial applications. These seeds may give an interesting source of bioactive lipids.  相似文献   
3.
The article aims to analyze the current state and determine the perspectives for oilseed rape production for energy purposes in Poland. According to the study, in recent years the oilseed rape area for energy purposes and the production of biocomponents and biofuels from oilseed rape have been on the rise in Poland. The considerable and spatially concentrated energy potential of oilseed rape in Poland is noted. It is indicated that the greatest energy potential of the oilseed rape production is the four neighboring voivodeships: Dolno?l?skie, Opolskie, Wielkopolskie, and Kujawsko-Pomorskie.  相似文献   
4.
李月梅 《中国油料》2012,(2):174-180
利用大田试验研究氮、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%、P2O57.8%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   
5.
A batch pilot-scale apparatus is described for the study of processes for obtaining phyto-extracts using solvents. The distinctive feature of the equipment is that it provides the efficiency of a multi-stage counter-current extraction, yet uses only a single batch extractor (as opposed to a battery of extractors). This is achieved by using an auxiliary tank in which intermediate extracts are saved and recirculated in a pre-established order. Careful design of the mechanisms for the circulation of liquid from such tanks has resulted in an apparatus that is compact and has simple, flexible operation. A prototype of this apparatus was constructed for the study of the direct extraction of oil from sunflower seeds using hexane A simple model that describes the operation of the equipment is presented and applied to our experimental work with oilseeds.  相似文献   
6.
目的 建立分散固相萃取结合液相色谱-串联质谱同时测定油料油脂中67种除草剂残留的检测方法。方法 选取花生、大豆、油菜籽、花生油、大豆油及菜籽油为典型基质试样,经1%甲酸-乙腈提取,通过乙二胺基-N-丙基和无水MgSO4分散固相萃取净化。以甲醇和5 mmol/L乙酸铵(含0.1%甲酸)为流动相梯度洗脱,采用C18色谱柱分离,ESI离子源正负离子模式同时进行多反应监测(MRM),基质标准曲线外标法定量。结果 基质加标试验结果表明,0.000 5~0.08 mg/L浓度范围内67种除草剂线性良好,决定系数(R2)均>0.992,定量限(LOD)为0.005~0.02 mg/kg。3个加标水平下(LOD、2LOD、10LOD)的回收率为62.3%~118.1%,RSD(n=6)均<15%。结论 本方法稳定性高、特异性强、灵敏、准确、高效,可以用于油料油脂中多种除草剂残留的定性定量检测。  相似文献   
7.
Thirty-six lactating multiparous Holstein cows were assigned to diets that contained 2.3, 4.0, and 5.6% fat for an entire lactation to determine the effect of oilseeds on milk composition, production, and methane emissions. The diets were formulated so that whole cottonseeds and canola oilseeds provided equal amounts of added fat. Methane emissions were measured every 3 mo from two replicates of four cows per treatment using a room tracer approach. Dry matter intakes and yields of milk and FCM were greater for cows fed the diets containing oilseeds. Although the concentration of protein in milk was reduced, yields of both protein and fat tended to be increased by the addition of fat. Within the milk fat, the concentrations of C10, C12, C14:0, and C16:0 were reduced and concentrations of C18, C18:1, and trans-C18:1 were increased in response to dietary oilseeds. In serum, urea-N was increased by the dietary oilseeds. Supplementation of diets with oilseeds did not affect methane emissions but tended to increase the efficiency of milk produced per unit of methane emitted. A 1.7% addition of fat to the control diet from a combination of oilseed types increased yields of milk without reducing methane emission rates. The strategy of using unsaturated fats from oilseeds to substantially reduce methane emissions was ineffective, although yield of milk was increased.  相似文献   
8.
Galactinol, 1-O-α-D-galactopyranosyl-D-myo-inositol, is an essential intermediate in the biosynthesis of raffinose saccharides in plant tissues. The unavailability of a commercial source for this metabolite has hindered research on raffinose saccharide metabolism to date. The objective of this study was to develop a facile method for obtaining highly purified galactinol from a readily available source. Defatted castor oilseed meal was found to exhibit a simple soluble carbohydrate profile that included galactinol. Purification of galactinol from castor meal was achieved by enzymatic treatment and a series of liquid chromatography steps, including ion-exchange and carbon adsorption. The isolation procedure was reliable with a yield of 278 mg of galactinol from 150 g of defatted meal. The purity of galactinol was estimated at 96.4% by high-performance liquid chromatography. The identity of the purified galactinol was confirmed by enzymatic analysis, identical relative retention times on high-performance liquid chromatography and gas chromatography, and comparison of its mass spectrum to that of authentic galactinol. Presented at the AOCS Annual Meeting in Chicago in May 1991 [INFORM 2:334 (1991)].  相似文献   
9.
Effects of added Cd on Cd uptake by oilseed rape and pai-tsai co-cropping   总被引:2,自引:0,他引:2  
The experiment was designed to study whether the decrease of Cd in the rhizosphere of Zhongyouza Ⅰ,one breed of oilseed rapes (Brassicajunica) that can hyperaccumulate cadmium from the soil, can improve the living condition of less Cd-tolerant plant pai-tsai (Brassia chinensis) with their roots permitted to intermingle and develop coincident rhizosphere. The extent of rhizosphere interactions between Zhongyouza Ⅰ and pai-tsai was controlled by different root barriers, or without barrier. The results show that in the 10 and 20 mg/kg Cd treated soils, pai-tsai gets higher shoot mass and less Cd accumulation in its shoot than in the barrier treatments or in the mono cultures, when its roots are permitted to intermingle with those of Zhongyouza Ⅰ. Meanwhile, soil decontamination rates of Zhongyouza Ⅰ are not affected much by co-cropping with pai-tsai, they are 80.0% and 91.8% of that in the mono cultures of Zhongyouza Ⅰ, respectively. However, the co-cropping method in meliorating the living condition of pai-tsai is not obvious when Cd concentration in soil reaches 40 mg/kg, and soil decontamination rate decreases to 0.14, which is 58.3% of that in the mono culture. These results indicate that the oilseed rape Zhongyouza Ⅰ may alleviate Cd toxicity of surrounding less-tolerant species, and its ability of phytoremediation is not affected much at the same time, especially in the middle polluted soil.  相似文献   
10.
A rapid X-ray spectrometric (XRS) method has been developed for the determination of the total glucosinolate content of oilseed rape and other Brassica oilseeds. The method is based on analysis for fully oxidised sulphur (S6+), which includes half the sulphur (S) in the glucosinolate molecule, and the S in sulphate. Results are highly correlated with glucosinolate content determined by glucose release, a standard method widely used in Australia. The relationship is total glucosinolates = (23·97 S6+ -9·43) r2 = 0·987, where the glucosinolate content is expressed as μmol g?1 and the S6+ content in mg g?1. The relationship is applicable to seed of any glucosinolate content and to meal, and is unaffected by changes in protein sulphur content. The correlation of glucosinolates with S6+ is shown to be closer than the correlation with total S. The latter correlation forms the basis of the existing XRS method, used within the European Community in recent years. The advantages of S6+ derive from the linearity of the regression and the elimination of errors caused by variation in protein content. The method should be valuable to the Australian oilseed industry because it allows the rapid screening of breeding lines to ensure low glucosinolate content and the assessment of deliveries for crushing and of meal.  相似文献   
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