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1.
直播油菜施肥效应及适宜肥料用量研究   总被引:22,自引:2,他引:20  
采用“3414”肥料效应试验设计方案进行田间试验,探讨直播油菜氮磷钾(NPK)肥效应及肥料的适宜用 量。结果表明,NPK配合施用显著提高了油菜产量,三因素增产大小顺序为N >K >P;油菜各器官养分含量和积 累量随相应养分的施用明显提高;试验条件下,N、P2O5和K2O用量为180、30和90kg/hm2时,氮磷钾肥表观利用 率最大,分别为35.1%、23.1%和73.9%。用一元二次肥料效应模型对试验结果进行模拟,结果显示,直播油菜N、 P2O5和K2O适宜施用量为212、23和112kg/hm2。  相似文献   

2.
麦套花生优化施肥研究   总被引:4,自引:2,他引:2  
采用三因素二次饱和D—最优设计,建立了麦套花生N、P、K施肥与花生产量间的数学模型。由模型可得:(1)N、P、K三种肥料对麦套花生产量作用显著,且互作间存在较大的交互效应,因此,N、P、K需配合使用。(2)公顷产量4500~5250kg的优化施肥方案为:每公顷施N109.5~147kg,P2O5133.5~186kg,K2O243~348kg;最优组合为:每公顷施N139.6kg,P2O5174.3kg和K2O323.3kg,最高产量可达5260kg/hm2。  相似文献   

3.
采用三因素二次通用旋转回设计研究了冬小麦施用氮,磷,钾对籽粒产量,冬前叶片中糖分含量,苗期单株干重等性状及经济效益的影响,通过取样调查,测产,建立了上述性状的数学模型,分析了有关因子的主效应及交互效应,提出了施肥方案,即在保证产量每公顷4000kg的条件下,每公顷施N172.27~204.22kg,P2O587.93~112.45kg,K2O44.2~63.46kg,N:P2O5:K2O为1:0.  相似文献   

4.
黄土高原向日葵产量的土壤养分限制因子与施肥指标研究   总被引:3,自引:0,他引:3  
1994~1996年在黄土高原陕西渭北旱塬进行了向日葵的养分限制因子与高产高效施肥试验,结果表明,N、P、K是向日葵产量的限制因子。Fe、Zn、Mg、Cu、Mn、B为非限制因子,限制因子对向日葵的产量效应K>N>P,经济效应最佳施肥指标N163.21~169.89kg/hm2,P2O5128.60~131.91kg/hm2,K2O181.37~190.09kg/hm2。  相似文献   

5.
适宜的移栽密度、科学的肥料运筹是实现棉花超高产量重要的因素。里下河棉区大麦后移栽棉适宜的密度为4.5万株.hm^-2左右,最佳施肥水平337.5kg.hm^-2,N:P2O5:K2O为1:0.4:0.8,施肥水平、肥料配比及密度对单株果枝数影响较大,单位面积果枝数、总果节量的多少主要取决于密度大于。在施N水平较高的情况下对单株果枝数影响较大,单面积果枝数、总果节量的多少主要取决于密度大小。在施N水平提高的情况下(>262.5kg.hm^-2),单株成铃数、铃重及产量随施钾水平的提高而增加。  相似文献   

6.
本试验在固定P、K肥下,研究有无农家肥[F1(1500kg/亩),F0(0kg/亩)]下不同施N量(0,2.5,5.0,7.5kg/亩)对马铃薯(品种疫不加)生长发育、矿物质营养吸收及产量品质的影响。结果表明:随施N量增加,叶面积、茎叶生长量、净同化率及块茎膨大速率也增加,N7.5处理明显优于N2.5及N0处理。施N增加了N的吸收,特别是N7.5处理,对P、K的影响不大,同时,也增加了N、P、K的转运率。有农家肥时增强了上述作用。最高产量施N为7.5kg/亩。N7.5F0处理鲜产为1604.98kg/亩,N7.5F1处理为1613kg/亩。F0时N肥的产量效应方程为Y=1290.14+74.3X,F1时效应方程为Y=2619.870+76.234X-2.40X2(X从0→7.5kg/亩)。且随施N增加,淀粉含量有下降趋势,而淀粉产量逐渐增加,N5.0F1处理的淀粉产量为178.51kg/亩。  相似文献   

7.
长达15年的田间石灰长期定位试验结果显示:红壤施用3.75~15.00t/hm2石灰石粉降低土壤酸度的后效可以维持4~15年,使油菜增产和肥料利用率提高所维持的时间则可达15年以上。红壤施用石灰可以提高油菜籽粒产量17.5%~29.8%,提高N、P和K肥料利用率的幅度分别为17.6%~33.0%,25.6%~39.7%和6.8%~36.1%。  相似文献   

8.
本文于1988~1990年采用五因素五水平二次正交旋转回归设计的方法,对影响淮北地区麦套棉花产量和效益的人为可控因子中的施纯N量、P2O5量、K2O量、密度、化控5个因子进行了研究。通过建立的数学模型,明确了对产量和效益影响的主次顺序为:密度>氮肥>钾肥>化控>磷肥,并得到了达到最高产量和效益的最佳组合方案:每公顷施纯N180~195kg,P2O530~60kg,K2O150~165kg,移栽密度5.25万~5.51万株/hm2,缩节安用量30~45g,于盛蕾期、盛花期或封顶时化调2~3次。为生产上制定技术措施提供了科学依据。  相似文献   

9.
水肥措施对春小麦产量及其构成因素的影响   总被引:2,自引:0,他引:2  
本文就不同水肥措施对坝上春小麦产量及其构成因素的影响进行了研究。结果表明,在自然降雨的基础上,进行补水可以显著地提高产量,并以在小麦需水关键期—拔节期和孕穗期补水150mm产量最高,补水225mm(三次)则降低产量.施肥可显著增产,水分和肥料间互作效应显著,以补水150mm、施N180kg/hm2、施P120kg/hm2产量最高.肥水措施可显著增加穗粒数和穗粒重,而对千粒重影响不显著.  相似文献   

10.
盆栽条件下,应用(15)N示踪技术,研究了不同施N水平(每公斤土施用0.1克、0.2克氮)下,不同熟期大豆品种吸收、利用氮肥的差异。结果表明,植株全氮积累量:中晚熟品种>早中熟品种>早熟品种;施氮对增加各品种植株氮的积累有明显影响,其大小顺序为早中熟品种>早熟品种>中晚熟品种,而且增产作用显著,增产率分别为N1:24.1%-40.7%和N218.5%-61.9%;植株中肥料氮占总氮的比例分别为23.5%-43.6%和50.5%-68.2%.其大小依次为早熟品种>早中熟品种>中晚熟品种;至成熟期,68.8%-81.8%肥料N转移到籽粒中,早熟和早中熟品种高于中晚品种.  相似文献   

11.
12.
Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.  相似文献   

13.
Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.  相似文献   

14.
15.
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.  相似文献   

16.
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.  相似文献   

17.
Novel food and non-food uses for sorghum and millets   总被引:4,自引:3,他引:4  
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.  相似文献   

18.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

19.
Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X1 (also called RXact).  相似文献   

20.
The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.  相似文献   

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