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71.
The juveniles of Macrobrachium rosenbergii (0.060 ± 0.004 g and 2.018 ± 0.071 cm) were fed during 60 days with diets containing different doses of Lippia alba essential oil (EOLA) (0.0—control, 1.0, or 2.0 ml EOLA/kg diet; in triplicate, with 20 prawns/replicate). After the experimental period, were verified the survival, growth parameters and the antioxidant enzymes, lipid peroxidation and Na/K‐ATPase activities in hepatopancreas and gills, respectively, of the animals. There were no significant differences on survival, growth parameters and gill Na/K‐ATPase activity. However, glutathione peroxidase and glutathione‐S‐transferase activities were lower in hepatopancreas of prawns fed with 1.0 ml EOLA/kg diet compared to the control. Moreover, the activity of the enzyme superoxide dismutase was higher in hepatopancreas of prawns that received 2.0 ml EOLA/kg diet compared to those fed with 1.0 ml EOLA/kg diet. Although the addition of both EOLA doses has not improved the survival and growth parameters of M. rosenbergii, these doses contributed to decrease lipid peroxidation. Additionally, the dose of 2.0 ml EOLA/kg diet contributed for increasing the antioxidant enzymes activities in the hepatopancreas, improving antioxidant status, and therefore, it can be recommended as diet supplementation for M. rosenbergii.  相似文献   
72.
The zootechnical performance of fish can be influenced by temperature through the induction of metabolic changes that are likely to affect growth and body composition. Thus, the objectives of this study were: (a) to examine the influence of five different temperatures (18, 21, 24, 27 and 30°C) on growth performance and metabolic parameters and (b) to evaluate the relationship of the protein efficiency ratio (PER) with the fillet proximate composition of Pacu juveniles. Growth and feed consumption (FC) were positively correlated with temperature (R2 = .95), while PER and FC were negatively correlated with temperature (R2 = .89). For the fillet composition, ethereal extract increased, and moisture decreased with the temperature. Protein content was lowest at 18 and 30°C and highest at 21, 24 and 27°C. The robust adjusted curve between PER and fillet protein content in relation to temperature showed the best result at 21°C. The obtained results indicate that Pacu juveniles reared between 21 and 27°C showed better protein efficiency with regard to FC, and this effect reflected better meat quality.  相似文献   
73.
甘蔗赤腐病病原菌的分离与ITS序列鉴定   总被引:1,自引:0,他引:1  
从甘蔗赤腐病病原菌分离纯化得到5株病原真菌(CF-1、CF-2、CF-3、CF-4、CF-5),对其进行致病性测定、形态学观察和ITS序列分析。结果表明,CF-1和CF-4均能引起与田间病害一致的症状,通过ITS1和ITS4对致病菌的基因片段进行扩增,结果显示,菌株CF-1与KU933924.1相似性达到99.00%,CF-4与MH854879.1相似性达到99.42%。综合病害症状观察、形态观察和ITS序列分析结果,将甘蔗赤腐病病原菌CF-1鉴定为镰形炭疽菌(Colletotrichum falcatum Went.),将CF-4鉴定为球黑孢菌[Nigrospora sphaerica (Sacc.) E.W. Mason.]。  相似文献   
74.
以云南农业大学自育的甘蔗品种滇蔗01-58为试验材料,以芦丁为标准品,采用分光光度计法研究滇蔗01-58叶片中总黄酮的最佳提取条件。以提取率作为指标,测定不同类型甘蔗[野生种、栽培品种(系)]叶片中黄酮含量。结果表明,基于单因素和正交试验的最佳提取条件为乙醇浓度70%、提取温度70℃、提取时间90min;不同类型甘蔗叶片的黄酮提取率有明显差异,栽培种黄酮含量最高的为滇蔗09-38,野生种黄酮含量最高的为五节芒Ι91-27,总体表现为野生种叶片中黄酮含量高于栽培品种(系)。  相似文献   
75.
芦竹内生真菌F0238对西红柿的生物保鲜研究   总被引:2,自引:1,他引:1  
从黄海海岸芦竹中分离到一株木霉属的内生真菌F0238。研究结果表明,F0238菌发酵4d后的发酵液对西红柿的防腐保鲜作用与化学保鲜剂多菌灵和甲基托布津的混合液无显著差异,有良好的生物保鲜作用。  相似文献   
76.
为探究甘蔗促生长菌株B9对不同基因型甘蔗品种的促生长效果,本研究采用6个不同基因型的甘蔗栽培种作为研究对象,以接种菌株与否分为处理组及对照组(CK),分别测定各甘蔗幼苗的株高、根长、鲜重、干重、株高、茎径、茎长等农艺性状以及叶绿素含量、根系活力、可溶性糖、可溶性蛋白等生理指标。通过综合生理指标及各方面农艺性状分析B9菌株对不同基因型甘蔗的促生长情况。由试验结果可知,在接种B9菌株后,不同甘蔗品种在株高、茎径、叶长、叶片数、地下部分和地上部分的鲜重、干重等农艺性状均显著优于CK;同时处理组中各甘蔗品种叶绿素含量、植株光合指标、蛋白质含量、可溶性糖含量、谷氨酰胺合成酶(GS)及谷氨酸合成酶(GOGAT)活性、根系活力等生理指标较CK均明显提升,其中’桂糖11’在叶绿素含量、气孔导度(Gs)、可溶性糖含量、谷氨酰胺合成酶活性等方面促进效果较为显著;对’粤糖93-159’的谷氨酸合成酶活性促进效果最为显著;’柳城09-182’的可溶性蛋白含量、根系活力等方面相比其余品种增幅最大;’滇糖01-58’中净光合速率(Pn)和蒸腾速率(Tr)促进效果最佳。可见,内生菌B9对不同基因型的甘蔗品种均存在一...  相似文献   
77.
目的内生枯草芽孢杆菌B9菌株是一株分离于甘蔗根部的内生枯草芽孢杆菌,探究其促生长作用及产吲哚乙酸(IAA)能力,为下一步将其研制成高效微生物肥料接种剂提供理论依据。方法以玉米种子、甘蔗单芽茎和甘蔗组培苗为供试材料,通过浸泡接种玉米种子与甘蔗单芽茎,明确B9的最适促生长密度,观察它们的生长势并测定芽长、根长、株高、生根数和根系重量;通过灌根接种甘蔗组培苗,观察试管组培苗中根系长势,测定盆栽组培苗根长、株高、根系活力、氮代谢相关酶活性、叶绿素以及光合指标,运用液质联用仪检测无菌上清液中与促生长相关的IAA的含量。结果B9菌液稀释后对玉米种子和幼苗均有一定的促生长作用,随着菌液稀释倍数的增加,促生长效果呈先增加后减弱的趋势,在1.0×106 CFU/mL时,对玉米生长情况的影响达到最佳。甘蔗单芽茎经1.0×106 CFU/mL的B9菌液处理后,其相关的形态和农艺性状均显著优于清水对照(P<0.05)。在该密度下,甘蔗组培苗的株高、根长、叶绿素含量、谷氨酰胺合成酶(GS)、谷氨酸合成酶(GOGAT)、叶片净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)和根系活力等指标均明显优于CK。在LB培养基B9菌液中,吲哚乙酸含量增加明显,在9 d时达到(95.63±2.33) ng/mL,比空白对照增加1054.9%。在Landy培养基菌液中,同样检测到吲哚乙酸呈不断增长的态势,在9 d时比对照高出2.56倍。结论B9菌株对甘蔗和玉米均具有明显的促生长效果,且发酵液中的IAA分泌能力强。  相似文献   
78.
Soil and its ecosystem functions play a societal role in securing sustainable food production while safeguarding natural resources. A functional land management framework has been proposed to optimize the agro‐environmental outputs from the land and specifically the supply and demand of soil functions such as (a) primary productivity, (b) carbon sequestration, (c) water purification and regulation, (d) biodiversity and (e) nutrient cycling, for which soil knowledge is essential. From the outset, the LANDMARK multi‐actor research project integrates harvested knowledge from local, national and European stakeholders to develop such guidelines, creating a sense of ownership, trust and reciprocity of the outcomes. About 470 stakeholders from five European countries participated in 32 structured workshops covering multiple land uses in six climatic zones. The harmonized results include stakeholders’ priorities and concerns, perceptions on soil quality and functions, implementation of tools, management techniques, indicators and monitoring, activities and policies, knowledge gaps and ideas. Multi‐criteria decision analysis was used for data analysis. Two qualitative models were developed using Decision EXpert methodology to evaluate “knowledge” and “needs”. Soil quality perceptions differed across workshops, depending on the stakeholder level and regionally established terminologies. Stakeholders had good inherent knowledge about soil functioning, but several gaps were identified. In terms of critical requirements, stakeholders defined high technical, activity and policy needs in (a) financial incentives, (b) credible information on improving more sustainable management practices, (c) locally relevant advice, (d) farmers’ discussion groups, (e) training programmes, (f) funding for applied research and monitoring, and (g) strengthening soil science in education.  相似文献   
79.
为解决化肥用量过多问题,提高甘蔗节本增效,选取云南省6个主要蔗区作为试验点,以B9菌剂、有机肥、复混肥不同组合为供试肥料设置不同施肥处理,探讨各肥料处理对甘蔗生长、产量、糖分等农艺性状的影响,并分析甘蔗种植效益。结果表明,施用B9菌剂组合的肥料不同程度促进甘蔗出苗;6个试验点中除盈江县和景谷县施用B9菌剂组合的肥料对促进甘蔗分蘖作用不明显外,其他4个试验点均达到有效促进;与普通复混肥处理相比,施用B9菌剂的处理在株高、茎径、有效茎数、蔗茎产量、蔗糖分等性状有一定程度的增加,但影响不显著。选取元江县进行经济效益分析,结果表明,施用B9菌剂组合的肥料比对照收益高,而没有B9菌剂组合的肥料比对照低。综上所述,施用“B9菌剂+有机肥+化肥”组合的肥料在稳产减肥(化肥)方面起到了积极的作用,值得应用推广。  相似文献   
80.
"中央水利工作会议明确提出,要下大气力在全国大规模开展农田水利建设,健全农田水利建设新机制,全面提高农业用水效率,持续改善农业水利基础条件,显著提高农业综合生产能力。  相似文献   
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