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91.
为了探明干旱环境下风蚀和水蚀对DSE(Dark septate endophytes)活动的影响,试验于2013年6月选取内蒙古正蓝旗青格勒图梁地,设置梁底、梁坡和梁顶不同样地,从羊柴(Hedysarum laeve)根围0~10、10~20、20~30、30~40、40~50cm土层采集土壤样品,研究了DSE分布规律以及与AM(arbuscular mycorrhiza)真菌和土壤因子的相关性。结果表明:羊柴根系能被DSE高度侵染,形成典型的有隔菌丝、微菌核和泡囊等共生结构。样地对DSE定殖率有显著影响,DSE菌丝、泡囊和总定殖率梁底梁顶梁坡,AM真菌定殖率梁底梁坡梁顶。相关性分析表明,DSE定殖率与AM真菌定殖率显著正相关,与土壤酸性和碱性磷酸酶极显著正相关。受风蚀和水蚀影响,3个样地土壤养分差异明显,梁底受侵蚀作用最弱,梁坡最强;DSE定殖和分布具有明显空间异质性,梁底显著高于其它样地,梁坡最低,DSE定殖状况能够良好的指示内蒙古梁地土壤环境的变化。这为进一步明确DSE生态功能,利用DSE资源促进干旱地区植被恢复和水土保持提供依据。  相似文献   
92.
[目的]为探明AM真菌对烤烟生长发育的影响。[方法]本试验以云烟87为材料,通过大田试验,研究了AM真菌对烤烟农艺性状、病害发生情况和经济性状的影响。[结果]与对照相比,AM真菌能有效促进烤烟幼苗根系生长,增加烤烟幼苗生物量积累,提高田间烤烟株高和最大叶面积,降低田间烟株发病率和发病指数,提高烤后烟叶产量。[结论]在育苗期间育苗基质中施入AM真菌能有效促进烟株生长发育,提高烤后烟叶经济效益。  相似文献   
93.
接种丛枝菌根真菌对甘薯生长的影响研究   总被引:10,自引:0,他引:10  
温室盆栽试验研究 3种丛枝菌根真菌 (AM )对甘薯生长的影响结果表明 ,灭菌土壤条件下接种 3种AM真菌 (GlomusmosseaeBEG16 7GlomusintraradicesBEG14 1和Glomussp .WUM2 6 )均不同程度促进甘薯对P的吸收和植株生长 ,其中BEG16 7和BEG14 1对甘薯效应显著高于WUM2 6 ;各接种处理菌丝长度差异及琥珀酸脱氢酶(SDH)活性与其对甘薯的生长效应基本一致 ;接种BEG16 7和BEG14 1的生长效应无显著差异 ,但接种BEG16 7菌丝长度显著大于BEG14 1,其原因可能是BEG16 7菌丝活性低于BEG14 1所致。未灭菌土壤条件下接种 3种AM真菌对甘薯的生长效应不显著 ,而土著AM真菌繁殖体数量较多可能是影响其接种效果的主要原因。  相似文献   
94.
丛枝菌根真菌的生物多样性研究进展   总被引:10,自引:1,他引:10       下载免费PDF全文
盖京苹  冯固  李晓林 《土壤》2005,37(3):236-242
由于进化历程和生存条件的差异,丛枝菌根(AM)真菌的发生、分布和功能都具有多样性特点。本文简述了近年来AM真菌在系统分类,种的多样性和功能多样性方面的研究成果,分析了当前研究中所存在的问题和动向。  相似文献   
95.
利用盆栽试验研究了NaCl胁迫条件下AM真菌对紫花苜蓿(Medicago sativa L.)植株生长及生理特征的影响。结果显示:随土中加入NaCl浓度增高(0%,0.5%,1.0%),与未接菌紫花苜蓿相比,接种AM真菌显著(P<0.05)促进紫花苜蓿生长,并使其可溶性糖、可溶性蛋白及根系脯氨酸累积量增加。1.0%NaCl接种AM真菌处理下根系鲜重(28.1 mg)为0%NaCl未接种下的1.27倍;不同盐处理接种AM真菌植株丙二醛含量均低于对照株;1.0%NaCl浓度下接种AM菌植株叶片及根系脯氨酸含量分别为对照株的0.82,1.41倍。表明AM真菌在胁迫环境下不仅可促进植株生长发育及渗透调节物质的积累,还可维持植物体丙二醛含量较低水平,降低植株遭受盐胁迫,推测叶片与根系脯氨酸对ABA依赖程度不同而导致其脯氨酸含量不同。  相似文献   
96.
供电企业使用的电力设施在管理上具有一个明显的特点,就是分散地分布在一个特定的地理范围内(如一个城市或一个地区),这给供电企业的设备管理带来了很多困难。多年来,电力企业的许多技术人员一直在探索实现“图数结合”技术和将地理信息引入到电力设施的管理上来,最近几年,AM/FM/GIS在国际国内得到广泛的应用。在分析电力系统基本情况的基础上,提出了基于MAPGIS的AM/FM/GIS系统模型。  相似文献   
97.
盐胁迫和AM真菌对生菜生长的效应   总被引:3,自引:0,他引:3  
郑义艳  冯固 《土壤学报》2006,43(6):966-971
试验设不接种、接种Glomus intraradices(BEG141)、接种Glomus mosseae(BEG167)3个接种处理,每个接种处理下再设电导率(EC)为607μScm^-1(低盐)、1236μScm^-1(中盐)、1866μScm^-1(高盐)等3个不同盐水平处理。试验结果表明:随着土壤EC值的增加,生菜生物量降低,但在低盐胁迫下,非菌根植株降低幅度大于菌根植株。与不接种处理相比,在低盐和中盐条件下,接种菌根真菌的植株体内NO3^-含量、植株地上部干重增加;同一土壤盐水平下,接种处理的植株磷、叶绿素含量高于不接种处理的;在低盐下,接种处理的植株的根系可溶性糖含量高于不接种处理的,但在1236和1866μScm^-1的盐度下,接种处理的植株根系可溶性糖含量低于不接种处理的。说明在施肥过量引起的次生盐渍化土壤中,AM真菌侵染对生菜在低盐胁迫下的生长存在促进作用,而在高盐胁迫下,使其生长受到抑制。  相似文献   
98.
Arbuscular mycorrhiza (AM) fungi form symbiotic relationships with the majority of land plants and are known for their positive effects on plant P acquisition and soil quality. The extramatrical growth of the mycelium is a key factor in nutrient acquisition by the symbiont. Soil grinding and extraction/fractionation of lipids were used in a field experiment to identify probable sources of the AM biomarker C16:1cis11 and its functional significance during reproductive growth of corn (Zea mays L.). Chambers, enclosed with a 1 mm mesh fabric to allow roots and hyphae to pass into the enclosed soil volume, were installed in two field sites cropped to continuous corn in central Nebraska. The chambers were installed at tasselling and removed after 3, 6 and 9 weeks. Soil from the chambers was analyzed by ester-linked fatty acid (EL-FAME) and chloroform-methanol fatty acid (CM-FAME) analysis. We also separated and analyzed the neutral lipid (NLFA), glycolipid (GLFA) and phospholipid (PLFA) fatty acid fractions. Roller milling the soil gave up to two-fold increases in the recovery of EL- and CM-FAMEs common to saprophytic fungi (C16:0, C18:1cis9, C18:2cis9,12) and AM fungi (C16:0, C16:1cis11, C18:1cis11) but not those specific to bacteria or fauna. Resistant AM fungal structures were enriched in NLFA and GLFA C16:1cis11, but not PLFA, indicating that storage lipids and possibly cell-wall lipids are released by roller milling. Similar proportional increases in C16:1cis11 on roller milling indicates that mild alkaline hydrolysis (EL-FAME) is as inefficient as chloroform-methanol (CM-FAME) in extracting lipids from AM spores. EL- and CM-FAME C16:1cis11 increased by one-third between R5 and R6, indicating C allocation from the plant to the AM fungus during the reproductive stages of corn. This increase was attributed to accumulation of NLFA and GLFA in lipid-containing structures of the extramatrical mycelium and AM structures within roots, not increased sporulation. We propose EL-FAME C16:1cis11 as a simple measure of AM biomass in soils that largely reflects the AM hyphal network important to nutrient acquisition by the plant.  相似文献   
99.
Abstract

The cultivation of horticultural crops, such as green peppers, tomatoes, eggplants and bell peppers is very common in semi-arid Mediterranean climate conditions. Two field experiments were performed to determine the effect of mycorrhizal species, plant species and phosphorus levels on mycorrhizal effectiveness and phosphorus (P) and zinc (Zn) nutrient uptake. In the first experiment, under field conditions, four plants species were inoculated with five arbuscular mycorrhizae (AM) species. In the second field experiment, under the same soil conditions, the same plant species were treated with three levels of phosphorus (P), i.e., control; 50?kg and 100?kg P2O5 ha?1. The most effective mycorrhiza species Claroideoglomus etunicatum selected in the first experiment was used in the second field first experiment. In the first experiment, fruit yield enhancement, yield increase, inoculation effectiveness and nutrient concentration in the plant leaves were analyzed. Under field conditions, plant species growth is strongly dependent on the species of AM fungi. Tomato and green pepper plants were inoculated with Cl. etunicatum, eggplants were inoculated with Funneliformis mosseae and bell peppers were inoculated with Rhizophagus clarus, which are high fruit-yielding plant species. In general, Fu. mosseae and Cl. etunicatum increased the yield of the tomatoes, green peppers and eggplants. It seems mycorrhiza species specific to plant species. In the second experiment, mycorrhizal inoculation with P fertilizer application, in particular a moderate amount of P (50?kg ha?1 P2O5) fertilizer increased the green pepper, bell pepper and tomato fruit yield compared with non-inoculated plants and non-P fertilizer application treatments. Increasing the application of P level reduced the mycorrhizal inoculation effectiveness (MIE). The results indicate that for all four solanaceae family plants 50?kg ha?1 P2O5 is a P level threshold for mycorrhizal development, which enhanced plant growth and addition of fertilizer over 50?kg ha?1 P2O5 reduced MIE. P and Zn uptake were significantly increased with mycorrhizal inoculation. These findings are supported by our hypothesis that mycorrhiza inoculation can reduce mycorrhizal dependent horticultural plants P fertilizer requirement.  相似文献   
100.
Studies were carried out on spatio-temporal variations of arbuscular mycorrhizal (AM) fungi associated with Carica papaya L. growing in two different geographic localities in Goa, India – Western Ghats and coastal area, differing in soil characteristics and plantation status. The study recorded considerable variation in root colonization, spore density and distribution of AM fungi in the selected sites. The mean total root colonization was at a maximum in the month of July, while spore density was highest in April. The study recorded a total 33 species of AM fungi. Western Ghats recorded a relatively higher diversity of AM fungi compared to coastal area. Species richness of AM fungi was at a maximum in April and coincided with maximum mean spore density. Edaphic as well as climatic factors influenced the AM fungal parameters. The study recorded the existence of seasonality in AM fungi.  相似文献   
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