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11.
There are few floral volatiles of compounds that have been properly assessed for attracting pollinators. The intense plant odour of Elsholtzia rugulosa (Lamiaceae) to humans may be attributed to the presence of high concentrations of β‐caryophyllene. In a previous study, Zhang, Yang, and Zhang (Scientific Reports, 6, 2016a, 276161) speculated that the presence of β‐caryophyllene attracts pollinators (e.g., honey bees) to its flowers, an assumption that was assessed through the exploration of the functional significance of specific floral volatile compounds and the evaluation of their effects on the behaviour of Apis cerana (Asian honey bees; a known pollinator) and two non‐pollinators, a hornet (Vespa velutina) and a bumblebee (Bombus sp.). The results from these behavioural experiments indicated that both β‐caryophyllene and β‐elemene (both naturally found in flowers of Erugulosa) were individually attractive to the Asian honey bees. Moreover, the combination of the two was more effective than either of them separately. In contrast, neither compound, nor a blend of the two at different concentrations, was attractive to the hornet and bumblebee species. These results demonstrate that β‐caryophyllene and β‐elemene play a key signalling role in attracting Asian honey bees to Erugulosa.  相似文献   
12.
叶大小-叶脉密度的权衡关系是植物叶经济谱理论的基础, 对理解资源竞争条件下植物叶片的物理构建与生理代谢的关系具有重要的意义。该文采用标准化主轴估计(standardized major axis estimation, SMA)的方法, 按芨芨草(Achnatherum splendens)株丛密度设置I (>12丛·m-2)、II (8-12丛·m-2)、III (4-8丛·m-2)和IV (<4丛·m-2) 4个密度梯度, 以叶面积和叶干质量分别表示叶大小, 对张掖洪泛平原湿地不同密度条件下芨芨草种群的叶大小和叶脉密度的关系进行研究。结果表明: 随着芨芨草株丛密度的降低, 湿地群落的土壤含水量逐渐减小、土壤电导率逐渐增加, 芨芨草的净光合速率(Pn)、蒸腾速率(Tr)和分枝数呈先增大后减小的趋势, 叶面积、叶干质量、比叶面积和株高呈逐渐减小趋势、光合有效辐射(PAR)和叶脉密度呈逐渐增加趋势; 芨芨草叶大小和叶脉密度在高密度(I)和低密度(IV)样地均呈极显著负相关关系(p < 0.01), 中密度(II、III)样地二者呈显著负相关关系(p < 0.05); 叶大小和叶脉密度回归方程的SMA斜率在不同密度样地均显著小于-1 (p < 0.05), 即芨芨草叶大小和叶脉密度呈“此消彼长”的权衡关系。在高密度湿地群落芨芨草倾向于大叶片低叶脉密度的叶片构建模式, 在低密度湿地群落选择小叶片高叶脉密度的异速生长模式, 体现了密度制约下湿地植物的生物量分配格局和资源利用对策。  相似文献   
13.
A pot experiment and a field experiment were conducted to investigate Cu-enriched composts made from Elsholtzia splendens plants as basal fertilizers to correct Cu deficiency in winter wheat (Triticum aestivum L.) grown in Cu-deficient soils. An application of the compost significantly increased plant height, biomass, grain yield, and 1000-grain weight. In the pot experiment, plant height and shoot biomass in the 2% Cu-rich compost treatment increased 0.8- and 5.2-fold compared with the chemical fertilizer treatment at the mature stage. Compared to chemical fertilizer control, the 2% Cu-enriched compost addition increased grain yield per pot by about 9.5-fold and 1000-grain weight by about 50%. In the field study, the compost also showed stimulatory effects on plant growth and grain yield. The results indicate that composting E. splendens plants grown in a Cu-contaminated soil and then applying the compost to a Cu-deficient soil may be an effective technique for the remediation of contaminated soils and redistribution of the copper as a plant nutrient for copper-deficient soils.  相似文献   
14.
铜矿区超积累Cu植物的研究   总被引:27,自引:3,他引:27  
1 引  言土壤重金属污染一直是环境污染问题之一 ,而且土壤中的重金属污染具有严重性、长期性和广泛性的特点[1 ,6] .但常规的一些物理化学方法因费用过高、对土壤性质破坏等一系列问题而难以广泛应用 ,植物修复为重金属污染带来了希望[5,7,9,1 3] .植物修复主要是基于重金属超积累植物 (hyper accumulator)的研究而兴起的 .超积累植物是指地上部分能富集重金属占干重的 1 0 0mg·kg-1 (Cu、Pb、Cd)或 1 0 0 0 0mg·kg-1 (如Zn)的一类植物[2~ 4,8] .在过去 2 0年内 ,已报道的超积累植物已有 4 0 0余种 …  相似文献   
15.
通过克隆海州香薷Actin基因片段并分析其组织表达,为研究海州香薷重金属抗性相关基因的表达调控奠定基础。根据Gen Bank中其他植物Actin基因保守序列设计兼并引物,以海州香薷根总RNA为模板,利用RT-PCR技术分离得到Actin基因片段。序列分析结果表明,海州香薷Actin基因片段长576 bp,编码192个氨基酸,与其他植物同源基因的氨基酸序列相似性为84%-97%,所克隆的序列为Actin基因的同源片段,将其命名为Eh ACT,在Gen Bank中提交序列,获得登录号AGT37260。半定量RT-PCR分析结果表明,Eh ACT在海州香薷的根、茎和叶中表达相对稳定,初步表明其可作为研究海州香薷基因表达的内参基因。  相似文献   
16.
长白山暗针叶林苔藓植物生物量的研究   总被引:9,自引:0,他引:9  
在长白山北坡暗针叶林对地面和树附生苔藓植物的生物量进行了测定.地面生苔藓采取样带调查取样法测定,树附生苔藓应用McCune方法对树干和树枝的附生苔藓生物量都做了细致的测定.结果表明,长白山暗针叶林中的苔藓植物分布很不均匀,随海拔变化差异很大,海拔1100m最低,仅为543kg·hm^-2;海拔1250m最高,达5097kg·hm^-2.苔藓植物生物量的变化对生境有很好的指示作用,特别是塔藓和拟垂枝藓的生物量随海拔的变化与森林系统的群落学特点有一定的相关性:在海拔1100~1700m,塔藓的生物量与臭冷杉的重要值变化趋势相近,随海拔升高而减少;拟垂枝藓的生物量与鱼鳞云杉重要值的变化趋势相似,随海拔升高而增加.此外,生物量随海拔的变化表明了不同苔藓植物对环境条件要求的差异,拟垂枝藓比塔藓水分条件要求更高.因此,生物量的研究在植物生理上也有一定的指示作用.  相似文献   
17.
In a laboratory experiment interaction effects of UV-B and CO2 on photosynthesis and growth of the moss Hylocomium splendens were studied. The plants were exposed to two CO2 levels (350 ppm and 600 ppm) and three UV-B levels (no UV-B, ambient UV-B and that corresponding to 20% ozone depletion) for 5 months. The effects were recorded by measuring the photosynthetic response and growth of the plants. There was a statistically significant change in photosynthetic efficiency and maximum photosynthetic rates due to time and to enhanced CO2 concentration, whereas there was no effect due to UV-B. There was a decreased growth due to both UV-B and CO2 and an interaction effect on growth (in length). The UV-B dose corresponding to the ambient level had a larger reducing effect on growth than the highest UV-B dose. This was a counter-intuitive result and the following tentative interpretation was made: differences in the measured UV-A/UV-B/PAR ratios between the treatments could explain the result provided there was a non-linear response to UV over the range of irradiance levels used.  相似文献   
18.
密花香薷的化学成分   总被引:7,自引:0,他引:7  
从密花香薷 (Elsholtzia densa Benth.)中分得 10个化合物 ,经波谱分析和化学方法鉴定为 :二十九碳烷 (1)、丁二酸 (2 )、5- (3″,3″-二甲基烯丙基 ) - 8-甲氧基呋喃香豆素 (3)、5- (3″-甲基丁基 ) - 8-甲氧基呋喃香豆素 (4)、5- (3″-羟基 - 3″-甲基丁基 ) - 8-甲氧基呋喃香豆素 (5)、3,4-二羟基肉桂酸 (6)、5-羟基 - 3′-甲氧基双氢黄酮 - 7- O-芸香糖甙 (7)、槲皮素 - 3- O- β- D-葡萄糖甙 (8)、山奈素 - 3- O- β- D-葡萄糖甙 (9)、5-羟基 - 4′-甲氧基黄酮 - 7- O-芸香糖甙 (10 )。其中 ,化合物 4和 5是新的天然产呋喃香豆素。  相似文献   
19.
《植物生态学报》2016,40(8):788
Aims Trade-offs between leaf size and vein density are the basis of the theory of leaf economics spectrum, and are to understand the relationship between the physical build and physiological metabolism of plant leaves under different degrees of competition for resources. Our objective was to study the changes in the relationship between leaf size and vein density (leaf dry biomass and leaf area) in Achnatherum splendens populations with four plant bundle densities located in the flood plain wetland of Zhangye. Methods The study site was located at floodplain wetlands of Zhangye, Gansu Province, China. Survey and sampling were carried out in the communities that A. splendens dominated. According to the plant bundle density, the A. splendens communities were divided into four density gradients with “bundle” for the sampling units, high density (I, > 12 bundle·m-2), medium density (II, 8-12 bundle·m-2), medium density (III, 4-8 bundle·m-2) and Low density (IV, <4 bundle·m-2). According to the density of each combination, we chose seven (5 m × 5 m) A. splendens samples, resulting in a total of 28 samples (4 × 7). The soil physical and chemical properties of four density gradients were investigated and six samples of A. splendens were used to measure the leaf area, leaf dry biomass and vein density in laboratory, and biomass of different organs was measured after being dried at 85 °C in an oven. 28 plots were categorized into three groups: high, medium and low density, and the standardized major axis (SMA) estimation method was used to examine the allometric relationships between leaf area, leaf dry biomass and vein density. Important findings The results showed that with the population density changed from high, medium, to low, the soil moisture decreased, and soil electric conductivityincreased. The leaf area, leaf biomass and height of A. splendens decreased, and the vein density, specific leaf area and photosynthetically active radiation (PAR) increased gradually. In addition, leaf net photosynthetic rate (Pn), transpiration rate (Tr) and twig number firstly increased then decreased. There was a highly significantly negative correlation (p < 0.01) between the leaf size and vein density on the high- and low-level densities (I, IV), whereas less significant (p < 0.05) on the level of medium density (II, III). The SMA slope of regression equation in the scaling relationships between leaf size and vein density was significantly smaller than -1 (p < 0.05).  相似文献   
20.
以海州香薷基因组DNA为模板,通过hiTAIL-PCR和walking技术扩增得到其细胞壁转化酶基因启动子(Ehcw INVP)片段,长度为1727 bp。生物信息学分析结果表明,该启动子片段中含有多个对脱落酸、赤霉素、细胞分裂素等激素以及对干旱、低温、重金属铜等逆境胁迫响应相关的顺式作用元件。将通过克隆得到的Ehcw INVP序列替换p CAMBIA1301载体上驱动GUS报告基因表达的Ca MV35S启动子序列,构建Ehcw INVP融合GUS的植物表达载体Ehcw INVP::GUS。转基因拟南芥植株的组织化学分析结果表明,海州香薷细胞壁转化酶基因启动子序列具有驱动GUS基因表达的功能,且在10μmol/L铜胁迫下,转基因拟南芥植株叶和根中的GUS活性分别约是对照组的1.7倍和1.5倍。  相似文献   
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