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1.
为明确氮肥和种植密度互作对寒地盐碱条件下水稻产量及干物质积累的影响,以龙粳21为材料进行试验。结果表明,水稻产量与施氮量、种植密度均呈显著的二次曲线关系,盐碱条件下龙粳21最佳产量的单因子施氮量和种植密度分别为169.9±5.0 kg/hm2和32.9±1.0 丛/m2。盐碱条件下中等施氮量和较高密度互作更易获得高产;高氮肥和高密度配合能够获得较高的齐穗期干物质积累量和LAI,但产量却显著下降;中等氮肥用量和中等密度配合能够获得较高的齐穗期剑叶光合速率,从而增加水稻产量。盐碱条件下高氮肥和高密度配合更易获得较多穗数,但中等施氮量和较低的密度配合更易获得大穗,氮肥和种植密度对千粒重不存在互作效应。因此,氮肥、种植密度科学合理配合,构建适宜的群体结构,才会发挥寒地盐碱地水稻的产量潜力。  相似文献   

2.
对杂交粳稻新组合辽99优15开展肥密效应研究,为该品种高产高效栽培提供依据。结果表明,当氮肥用量减少10%时,株高显著降低、氮肥偏生产力显著提高,而穗长、产量及其构成因素都没有明显变化;随着移栽密度的减小,穗长明显增加,穗数、千粒重、产量和氮肥偏生产力则显著降低,而穗粒数和结实率的变化不明显。氮肥用量和移栽密度仅在穗数上表现显著的互作效应。在现有常规氮肥用量的基础上,可以通过适当减氮和增密来获得高产并提高氮肥利用率。  相似文献   

3.
为探讨中花16的高产高效栽培技术,在田间试验条件下,研究了不同种植密度和肥力水平对中花16产量及农艺性状的影响。结果表明,随种植密度和肥力水平的提高,分枝数、结果枝数、荚果数和饱果数均呈下降趋势。不同肥力条件下,单株叶面积和群体叶面积系数表现一致,而不同密度条件下,两者差异明显。不同肥力与密度互作中F2×M1组合的产量达301.5kg/666.7m2,显著或极显著高于其他互作组合。综合分析认为,在本区域生态条件下,中花16作为露地春花生种植的适宜密度以0.85万穴/666.7m2为宜,肥料以一次性基施为好,基肥中应氮、磷、钾配合,并配施速效氮肥。  相似文献   

4.
为完善棉花-花生间作配套栽培技术,采用二次回归正交旋转组合设计,研究简化栽培模式下棉花与花生不同间作密度配置对产量的影响。结果表明:产量构成因素及密度与其产量关系较为紧密且复杂,同时棉花与花生也相互作用进而影响另一方产量;其中棉花产量构成因素与棉花密度互作对皮棉产量具有较高的正效应,但棉花密度的平方、花生株高与分枝数互作均对皮棉产量产生较高的直接负效应;花生密度与饱果数互作、衣分与花生分枝数互作对花生产量均具有较高的正效应,而棉花密度的平方、棉花株高与果枝数互作均对花生产量具有较高的负效应。在简化栽培模式下,棉花与花生的密度分别为3.75万株·hm-2和15.0万株·hm-2时,可以较好地协调群体和个体的关系,有利于棉花-花生间作总产量和总效益的提高。  相似文献   

5.
为探求豫南砂姜黑土区花生高产和氮肥高效利用栽培技术,采用大田试验,研究了氮肥管理与不同根瘤菌接种模式(拌种或土施)对花生生长、氮吸收利用及产量的影响。结果表明,施氮提高了花生叶片SPAD值,有效促进花生生长,显著增加了氮利用率和荚果产量。两种根瘤菌接种模式下,不同氮肥管理中均以50%N基施+50%N开花期追施和100%N基施处理的第一侧枝长、总分枝数、单株饱果数、单株饱果重和百果重、氮利用率和产量显著高于50%N开花期追施+50%N结荚期追施处理,说明要实现花生高产和氮素高效利用需在花生生育前期施用一定量的氮肥。比较根瘤菌拌种和土施2种接种模式,以根瘤菌拌种配施氮肥对花生的增产效果较好,但与根瘤菌土施配施氮肥处理间差异不显著。综合分析,在豫南砂姜黑土区,花生种植采用氮肥50%基施、50%开花期追施配合根瘤菌拌种的模式增产效果最好,氮肥利用效率最高。  相似文献   

6.
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   

7.
不同施肥量与种植密度对夏玉米产量及效益的影响   总被引:9,自引:0,他引:9  
王建华  高凤菊 《杂粮作物》2009,29(6):407-409
为了探索夏玉米在德州地区的最优栽培模式,采用裂区设计,对不同施肥量与种植密度时夏玉米的产量及效益的影响进行了试验研究。结果表明,施肥量及密度对夏玉米产量的影响均达到显著水平,且肥料和密度的互作效应显著。产量达629.58kg/667m2且效益最大的栽培措施是:追施氮肥30.4kg/667m2,种植密度4000株/667m2。  相似文献   

8.
针对长江流域双季稻机插秧发展缓慢的问题,以常规早稻品种中嘉早17为材料,在大田条件下研究了栽插密度与氮肥用量对机插双季稻产量的影响。结果表明,机插双季稻产量并未随栽插密度增加而显著增加。以高密(36.4万穴/hm2)+高氮(施纯氮量早稻175.5kg/hm2,晚稻189kg/hm2)处理产量最高,其中,早稻为7.80t/hm2,晚稻为9.05t/hm2,但与高密+中氮(施纯氮量早稻110kg/hm2,晚稻140kg/hm2)处理产量差异不显著,且栽插密度和施氮量间互作效应不显著。氮肥利用率随氮肥用量增加而下降,随栽插密度增加而提高。其中,氮肥吸收利用率中氮比高氮平均增加13.26%,高密度比低密度平均增加17.53%。由此可见,提高栽插密度,减少氮肥用量,既可通过大幅增加有效穗以实现高产,又能显著提高氮肥利用率。少氮密植可作为长江流域机插双季稻高产高效栽培的关键技术。  相似文献   

9.
为探明不同氮肥用量和机插密度对中熟中粳水稻新品种盐粳15号农艺性状、产量及构成因素的影响,于2020年在江苏省淮安市金湖县吕良镇江苏瑞华农业科技有限公司淮南试验站进行不同氮肥用量和机插密度的二因素裂区试验.结果表明:不同氮肥用量对盐粳15号的生育期、株高、产量及构成因素有显著的影响.随着氮肥用量的增加,盐粳15号的生育期延长,株高增高,高峰苗和有效穗数随之增加,但成穗率却随之减少,每穗总粒数先增加后减少,结实率降低,产量先升后降.不同机插密度对产量及构成因素有显著的影响,随着机插密度的增加,高峰苗和有效穗数随之增加,成穗率、每穗总粒数和结实率降低,产量先升后降.氮肥用量与机插密度之间有一定的互作效应.适当地增加机插密度可以弥补低氮水平下产量的损失,而在高氮水平下,机插密度应适度降低.综上,氮肥用量与机插密度分别为300 kg/hm2和27.8万穴/hm2时,盐粳15号生育期、株高适中,群体、穗粒结构协调,实现了最佳产量目标.  相似文献   

10.
采用裂区设计,研究了氮肥用量和插植密度对杂交粳稻辽优5206生长和产量性状的影响,为北方粳稻高产高效栽培提供依据。结果表明,随着施氮量增加,水稻分蘖数、抽穗期干物质量、拔节期SPAD值、株高和穗长显著增加,有效穗数、穗粒数和产量虽增加但不显著;随着栽插密度的增加,水稻分蘖数、干物质量、有效穗数明显增加,灌浆期SPAD值、株高、穗长、穗粒数显著降低,抽穗期SPAD值、结实率和产量则先增后降;氮肥用量和密度在产量等多数性状上互作效应不显著;取得高产的最佳肥密组合是240 kg/hm2和16.7万丛/hm2。  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:7,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.
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.  相似文献   

18.
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   

19.
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   

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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