共查询到20条相似文献，搜索用时 375 毫秒
1.
为确定早熟型冬小麦品种中麦8号在高肥力田达到最佳群体质量时合理的氮磷肥施用量和适宜的种植密度,采用两因素裂区试验设计,主区设4个氮磷肥施用量水平,分别为N120P96(纯氮120kg·hm~(-2)、P_2O_5 96kg·hm~(-2))、N_(180)P_(144)(纯氮180kg·hm~(-2)、P_2O_5 144kg·hm~(-2))、N240P192(纯氮240kg·hm~(-2),P_2O_5 192kg·hm~(-2))、N_(300)P_(240),(纯氮300kg·hm~(-2)、P_2O_5 240kg·hm~(-2));副区设3个种植密度,分别为D180(180万株·hm~(-2))、D240(240万株·hm~(-2))和D300(300万株·hm~(-2)),研究了氮磷肥和种植密度对小麦群体性状、产量及其构成的影响。结果表明,随着氮磷肥施用量的增加,小麦开花后干物质积累量和产量均降低;种植密度的增加提高了成熟期群体总茎数和单位面积穗数,而千粒重表现出相反的趋势。在N180P144至N_(300)P_(240),范围内,同一施肥条件下花后干物质积累量随种植密度的增加而增加。在土壤肥力较高的条件下,早熟品种中麦8号在种植密度180万株·hm~(-2)、施纯氮120kg·hm~(-2)和P_2O_5 96kg·hm~(-2)的条件下,产量达到最高。 相似文献
2.
玉米花生宽幅间作碳足迹初探 总被引：1，自引：0，他引：1
为明确玉米花生宽幅间作农田碳足迹,探索有效途径实现低碳与高效的协同效益,依据全生命周期评价分析原理,建立农田碳排放核算模型,设置农用物资(种子、肥料、农药、地膜)投入、农机能耗(耕地、播种、灌溉、收获)、秸秆处理及氮肥施用导致的田间N2O直接和间接排放四个模块,估算山东聊城地区典型玉米花生3∶4和3∶6宽幅间作与传统玉米单作、花生单作单位面积和单位产值的碳足迹差异。结果表明,3∶4和3∶6间作模式单位面积碳排放分别为3782.44kg CO_2e/hm~2和3829.94kg CO_2e/hm~2,均低于花生单作的3930.64kg CO_2e/hm~2、高于玉米单作的1361.38kg CO_2e/hm~2;二种间作模式的温室气体排放主要来自肥料(包括肥料生产、氮肥施用导致的田间N2O排放)和地膜,3∶4模式下占总排放的60.09%,3∶6模式下占60.54%;3∶4模式单位净产值的碳排放强度为0.197kg CO_2e/元,高于花生单作(0.179kg CO_2e/元)和玉米单作(0.154kg CO_2e/元),3∶6模式为0.177kg CO_2e/元,低于花生单作,但若能避免玉米条带的重复施肥和冗余翻耕,二种间作模式单位产值的碳排放强度将低于玉米和花生单作。玉米花生宽幅间作不仅提高土地产出率和资源利用率,而且具有显著的经济效益和生态效益。 相似文献
3.
为了充分发挥商豆1310的高产潜力,本试验采取五因素二次回归正交旋转组合设计的方法,研究了影响商豆1310产量的种肥、种植密度、追施尿素、多效唑和硼砂5项栽培技术之间的关系,建立了中等以上肥力产量形成的数学模型。经模拟寻优,筛选出了3 750 kg·hm~(-2)以上产量的最佳栽培量化组合方案,即施用种肥135.8～165.0 kg·hm~(-2),种植密度24.4～25.2万株·hm~(-2),追施尿素208.5～232.5 kg·hm~(-2),喷施多效唑1 932.0～2 140.0 g·hm~(-2)、叶喷硼砂1 147.8～1 432.2 g·hm~(-2)。本方案稍作修正后,经2点4.2 hm~2生产示范验证,平均单产3 799.05 kg·hm~(-2),较对照增产15.35%,证明方案可行。 相似文献
4.
为促进煤炭洗选加工废弃物尾煤泥在农业生产中的科学利用,以裸燕麦品种草莜1号和蒙农大燕1号为研究对象,尾煤泥基施量0(CK)、7 500、15 000、22 500kg·hm~(-2),在砂壤土田间进行随机试验,并对尾煤泥、土壤、燕麦茎叶的重金属和矿质营养成分进行了分析。结果表明,尾煤泥中的重金属镍(Ni)、铜(Cu)、锌(Zn)、铅(Pb)、铬(Cr)、镉(Cd)、汞(Hg)、砷(As)含量低于《城镇污水处理厂污泥处置:农用泥质》标准(CJ/T 309-2009)中的规定限量;尾煤泥显著(P0.01)提高了土壤与燕麦的氮(N)、钾(K)、钙(Ca)、镁(Mg)等养分含量及燕麦产量;两个燕麦品种对尾煤泥效应趋势一致;燕麦茎叶K含量与干草产量和籽粒产量的相关性最大,相关系数分别为0.446 8和0.571 1。综上所述,工业废弃物尾煤泥营养成分较高,可在土壤中安全施用,在燕麦种植中以15 000kg·hm~(-2)直接基施为宜,可提高砂壤土的容重10.48%,提高保水性(含水量提高16.84%),燕麦干草产量和籽粒产量两年平均提高42.79%和17.63%。 相似文献
5.
肥密互作对旱地冬小麦品种普冰151旗叶光合特性、产量及品质的影响 总被引：1，自引：0，他引：1
为给旱地冬小麦优质高产栽培提供参考,选用旱地冬小麦品种普冰151为试材,采用裂区试验设计,主区为施肥量,设229、459和688kg·hm~(-2)3个水平,副区为种植密度,设180×10~4、240×10~4、300×10~4和360×10~4株·hm~(-2) 4个水平,研究了施肥量和种植密度对普冰151旗叶光合特性、产量及品质的影响。结果表明,施肥量和种植密度均显著影响普冰151的旗叶光合特性,旗叶净光合速率(Pn)和SPAD值在施肥量为459kg·hm~(-2)和种植密度为240×104株·hm~(-2)时达到最高值。随施肥量增加,普冰151产量先升后降,在施肥量为459kg·hm~(-2)时最高;当种植密度为300×104株·hm~(-2)时产量最高。增加施肥量可显著提高普冰151的蛋白质含量、湿面筋含量和沉降值,稳定时间在施肥量为459kg·hm~(-2)时达到最大值;蛋白质含量、湿面筋含量和稳定时间随种植密度的增加先升后降,沉降值随种植密度增加而增加。在本试验条件下,实现普冰151高产和优质的适宜施肥量为459kg·hm~(-2),种植密度为300×104株·hm~(-2)。 相似文献
6.
新疆棉花//花生间作碳足迹研究 总被引：1，自引：0，他引：1
明确棉花//花生间作的主要碳排放环节,可为实现棉花//花生间作高产与低碳排放的协同效益提供有效参考措施.本文构建了碳足迹模型,按照全生命周期方法,核算了新疆棉花//花生间作生命周期碳排放.结果 表明:棉花//花生间作的净收益约为棉花单作的1.4倍、花生单作的1.2倍;棉花//花生间作的单位面积碳排放达4878.4 kg CO2-eq/hm2,较棉花单作降低10.9%、花生单作降低4.1%,但单位净产值的碳排放为0.4 kgCO2-eq/元,较棉花单作降低66.6%、花生单作降低29.6%.综合2种种植体系的净收益和单位净产值碳排放发现,棉花//花生间作可以实现高产出与低碳排放的协同效益,符合绿色、高产、高效农业发展需求. 相似文献
7.
《大豆科学》2020,(3)
为解决使用传统回归模型对大豆种植密度及施肥量进行优化时存在的拟合精度低、优化结果不准确等问题,提出一种基于RBF神经网络的优化方法。将大豆种植密度、N、P_2O_5、K_2O施用量作为试验因素,产量作为影响指标,选取黑河43作为试验材料,进行四因素五水平的正交旋转试验,获得各处理下大豆产量数据。对种植密度、施肥量与产量关系构建RBF神经网络拟合模型,对模型进行优化,得到最优种植密度42.65×10~4株·hm~(-2)、施N量61.82 kg·hm~(-2)、施P_2O_5量106.05 kg·hm~(-2)、施K_2O量19.81 kg·hm~(-2),该配比下大豆产量为3 821.48 kg·hm~(-2)。对优化结果进行试验验证,最优配比下大豆实际产量为3 742.29 kg·hm~(-2),与优化结果相对误差为-2.17%,表明该方法有效,且优化结果准确。 相似文献
8.
种植密度与施肥水平对山西早熟夏大豆产量与主要农艺性状的影响 总被引：2，自引：0，他引：2
为了确定汾豆98适宜的种植密度和施肥水平,以建立其高产优质栽培技术及其推广提供技术依据,本试验采用双因素完全随机区组设计,设置5个种植密度(37.50,48.75,60.00,71.25和82.50万株·hm~(-2))和4个施肥水平(450,600,750,900 kg·hm~(-2)),研究不同种植密度与施肥水平对大豆主要农艺性状、产量性状和产量的影响。结果表明:株高、结荚高度随种植密度增大而增加,主茎节数、分枝数、茎粗、单株荚数、单株粒数、单株粒重和百粒重均随种植密度的增大逐渐减少。株高、结荚高度、主茎节数、单株荚数、单株粒数、单株粒重和百粒重等农艺性状基本呈现高施肥水平大于低施肥水平的现象;其它农艺性状未表现出明显的规律。大豆产量随种植密度增大呈现先增大后减小的趋势,而其随施肥水平的升高呈逐渐增加的现象。汾豆98品种最适宜的种植密度是71.25万株·hm~(-2),在此种植密度下的最佳施肥量为900 kg·hm~(-2),最高产量为3 287.3 kg·hm~(-2),适当减小种植密度与施肥量也可取得较高的产量。 相似文献
9.
10.
<正>鲁6269于2012年通过山东省审定,该品种属于较典型的高产类型品种。2014年山东鑫秋农业科技股份有限公司第八农场承担高产创建项目,种植鲁6269面积8.0 hm~2,种植密度7.05万株·hm~(-1),成铃125.82万个·hm~(-2),实收子棉5725kg·hm~(-2)。现将其配套栽培技术总结如下:1播前准备1.1施足基肥。基肥要以有机肥为主,化肥为辅。每公顷施农家肥30~45 m~3、饼肥750 kg、施可丰复合肥(N、P、K含量15-15-15)375~450 kg,硼砂7.5~15.0 kg,硫酸锌15 kg。1.2翻地。基肥撒施后将地深耕,深度25~30 cm。 相似文献
11.
12.
Lakshman Lal 《Potato Research》1987,30(2):329-334
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.
《Journal of Crop Improvement》2013,27(2):81-114
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.
M. I. Siri P. Villanueva M. J. Pianzzola L. Franco Fraguas G. Galván M. Acosta F. Ferreira 《Potato Research》2004,47(3-4):127-138
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.
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
17.
Alejandro Carlos Tozzini María Fernanda Ceriani María Verónica Saladrigas H. Esteban Hopp 《Potato Research》1991,34(3):317-324
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.
Rita Favas Janaína Morone Rosrio Martins Vitor Vasconcelos Graciliana Lopes 《Marine drugs》2022,20(3)
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.
Alejandro M. S. Mayer Abimael D. Rodríguez Orazio Taglialatela-Scafati Nobuhiro Fusetani 《Marine drugs》2013,11(7):2510-2573
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