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1.
赣豆5号是国审优质大豆新品种,为探索该品种的最优高产栽培措施,为该品种的大面积推广应用提供科学依据,研究了不同播期、密度和氮肥追施量对赣豆5号产量及农艺性状的影响.结果表明,密度、播期、密度和氮肥互作效应对赣豆5号产量影响极显著,在施入等量的钙镁磷肥(375kg hm-2)和钾肥(150 kg hm-2)前提下,赣豆5号在6月29日播种,密度取12万株hm-2,氮肥追施量为300 kg hm-2,产量最高,经济效益最好.  相似文献   

2.
以春小麦巴07—6767为试验品种,采用L9(3^4)正交试验设计方法进行了肥料与密度研究。结果表明:在基施P20511.5kg/667m2,K208.33kg/667m2的基础上,试验处理A1B3C3D3(以底施氮肥4.5kg/667m2,分蘖期氮肥追施量6kg/667m2和拔节期氮肥追施量9kg/667m2,密度为60万/667m2)小麦产量最高,为533.4kg/666.7m2,经济效益最好,为1493.5元/666.7m2,投入与产出比为I:1.9。  相似文献   

3.
沈稻3号综合农艺措施的数学模型   总被引:2,自引:0,他引:2  
为了进一步挖掘沈稻3号增产潜力,采用规范化设计,研究了播种密度、插秧穴距、施氮量、施磷量和施钾量对沈稻3号产量的影响。结果表明,施氮量对沈稻3号产量的影响较大,在生产中应特别重视合理施用氮肥,合理搭配播种密度与施钾量、施氮量与施磷量是实现高产的重要措施。采用最佳模拟配合法,建立大于9375kg/hm^2的高产栽培农艺组合方案为播种密度76.08~78.35g/m^2,插秧穴距14,65~15.21cm,施氮量161.00-164.55kg/hm^2,施磷量39.92-41.51kg/hm^2,施钾量145.23~151,27kg/hm^2。  相似文献   

4.
玉米新品种绵单581高产栽培技术研究   总被引:1,自引:0,他引:1  
通过五因素二次回归正交旋转组合试验,建立了玉米新品种绵单581籽粒产量与种植密度(X1)、施氮量(X2),施磷量(X3),施钾量(X4),施锌量(X5)的数学模型。经用计算机进行因子水平寻优,得出产量在8550kg/hm^2以上的栽培模式为:密度45850—47538株/hm^2,施纯氮260.7~272、3kg/hm^2,施用P205为112.45—122、1kg/hm^2,施用K20为98.3~106.6kg/hm^2,施用ZnO为7.7~9.5kg/hm^2。  相似文献   

5.
为了探讨氮肥用量与插秧密度对超级早稻产量的影响,2007年在长沙、常德、郴州进行了大田栽培联合试验。结果表明不同施肥量处理间产量及有效穗数、每穗粒数、结实率、收获指数等产量构成因素差异显著.中早22产量与施氮量呈单峰曲线,以150kg/hm^2施氮量处理的产量最高(长沙7.5t/hm^2,常德9.4t/hm^2).在0~150kg/hm^2的施氮范围内增产效应最明显;陆两优996产量随施氮量增加而增加,以195kg/hm^2施氮量处理的产量最高。在30×10^4~36×10^4穴/hm^2的密度范围内,穗数与每穗粒数之间具有良好的互补性,因而密度间产量差异未达显著水平。本试验条件下,氮肥和栽插密度对产量的互作效应不显著。  相似文献   

6.
研究了不同N、P、K及密度配合,以及化控措施对赣豆4号产量和经济性状的影响。结果表明:处理6(A2B3C1D2)、8(A3B2C1D3)、4(A2B1C2D3)产量最高,分别为2835.84kg/hm^2、2818.08kg/hm^2和2816.28kg/hm^2。密度和K肥对产量影响达极显著水平,N肥影响达显著水平,而P对产量的作用不大。K能促进产量构成因子的形成,提高单株生产力。随着密度增大、N肥用量的增加,株高增加,分枝减少,单株荚数、粒数、单株生产力降低,百粒重减轻。P对促进分枝、提高单株荚数有一定的作用。多效唑、叶面喷肥、钼酸铵拌种、根瘤菌拌种分别比常规种植增产14.39%-5.16%。高产试验平均产量达2673.6-2814.3kg/hm^2,最高产量达3429kg/hm^2,高产示范平均产量2496.5kg/hm^2。  相似文献   

7.
氮肥追施量和比例对夏玉米产量的影响   总被引:10,自引:4,他引:10  
2002~2004年采用邢抗6号为材料,进行了夏玉米追氮量和施用比例的研究。结果表明:播种后第45天追纯N量150~337.5kg/hm2的范围内产量差异不显著,最大效益的追纯N量为225kg/hm2;在拔节期和大喇叭口期氮肥分次施用较大喇叭口期一次施用增产极显著,追施比例以4∶6最佳,纯N追施量在157.5~315kg/hm2的范围内产量差异不显著,最大效益纯N追施量为210kg/hm2;氮肥追施量与施用比例互作效应不显著。  相似文献   

8.
为优化亚麻栽培技术,提高亚麻原茎产量,试验通过二次正交旋转设计分析了有效播种密度、氮肥、磷肥、钾肥对冬播亚麻原茎产量的影响。发现供试条件下,各因素对亚麻原茎产量的影响大小顺序为有效播种密度(X1)〉氮肥(X2)〉钾肥(X4)〉磷肥(X3),不同肥料间互作不显著。并得到优化后的亚麻高产栽培方案:有效播种密度在3454.8-3502.3万粒/hm2,N263.2-337.7kg/hm^2,P2O5用量75.5-99.7kg/hm^2,K2O用量242.5-316.8kg/hm^2。  相似文献   

9.
2007年通过采用裂区试验设计,以氮肥为主处理,密度为副处理对慈杂1号进行密度与氮肥最佳组合筛选。结果表明:慈杂1号的最适组合为施纯氮405kg/hm^2,密度为33000株/hm^2,能较好协调个体与群体的生长关系,夺得最高子棉和皮棉产量。  相似文献   

10.
通过对泛玉5号密度与追肥量的研究结果表明:泛玉5号最佳种植密度为67500株/11m^2,最适追肥量为450kg/hm^2,产量为9166.5kg/hm^2。但密度和肥料各处理之间产量差异不显著,表明泛玉5号耐密性、耐肥性强,适应性广。  相似文献   

11.
12.
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   

13.
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   

14.
15.
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   

16.
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   

17.
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   

18.
The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O2•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O2•− scavenging, (IC50 = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC25 = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC50 = 863 µg/mL; elastase, IC50 = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O2•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.  相似文献   

19.
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   

20.
Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).  相似文献   

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