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41.
川东南马尾松外生菌根苗及其抗铝性研究   总被引:1,自引:0,他引:1  
刘敏  陈刚  李存英  黎勇 《北方园艺》2007,(11):205-208
采自西南地区分离的马尾松林常见的土著菌株松乳菇(Lactarius deliciosus 01,03)、彩色豆马勃(Pisolithus tinctorius 715)和模式种双色蜡蘑(Laccaria bicolor S238N)的基质纯培养物及液体纯培养物,分别按混合(Mix=Ld 01 Ld 03 Pt 715 Lb S238N)及单独接种的方式接种1月龄马尾松(Pinus massoniana)幼苗.菌根苗在不同pH土壤及铝胁迫条件下培育3个月后采样分析其生长和养分吸收特性.结果表明:4种接种方式均能有效形成菌根,显著增加幼苗的生物量,促进幼苗对N、P、K的吸收并显著(P<0.05)提高抗铝性;混合接种促进马尾松幼苗生长的效果较单独接种好,并且pH=6.1时,幼苗对K的吸收量最大,铝吸收量最少;pH=4.1时,幼苗对N、P的吸收效果最好,但对K的吸收和对铝的抗性最差.  相似文献   
42.
It is usually assumed that plant tissue responses to nutritional elements are due to specific genetic differences that may exist either between inbred or closely related species. Little Marvel (dwarf) and Alaska (normal) varieties of 14‐day old pea seedlings were treated with four different concentrations of Al‐containing nutrient solution (0.0mM, 0.2mM, 0.6mM and distilled H2O), prior to being exposed for 14 days to either DARK, LIGHT, or UV. Selected tissues (root tip, main root, main stem and proximal stem) were bioassayed for peroxidase and polyphenol oxidase enzyme activities, fresh wt vs. dry wt, water uptake and stem growth. The present study suggests that Little Marvel and Alaska pea tissue responds to high toxicity levels of Al by demonstrating an enhancement of enzymic activity. Tissue weight, growth and water uptake also show differential tissue specificity in both Little Marvel and Alaska tissue, in terms of Al toxicity response, given a particular external exposure.  相似文献   
43.
Abstract

The phytotoxicity of aluminum (Al) in relation to preculture with phosphates was examined in the rice cultivar Arkansas fortuna. In plants precultured with phosphates, Al did not inhibit shoot growth, while Al retarded shoot growth in plants precultured without phosphates. In contrast, Al inhibited root elongation, irrespective of the presence of phosphates in the preculture solution. A large proportion of the Al in roots was in unknown, insoluble forms. In phosphate‐precultured plants, Al deposition was slightly increased, presumably due to the formation of aluminum phosphates in the roots, and phosphorus levels in shoots were markedly increased. Binding with phosphates may ameliorate the toxicity of Al when it enters the shoots and account for the uninhibited shoot growth in the presence of Al in plants precultured with phosphates.  相似文献   
44.
【目的】探究在铝(Al)胁迫下不同含量的纳米氧化锌(Zinc oxide nanoparticles,ZnO NPs)对大豆Glycine max (Linn.) Merr.生理特性的影响,为金属纳米材料在农业上的应用提供一定参考。【方法】采用盆栽试验,选择耐Al品种‘华春2号’和普通品种‘华春6号’,在0.3 g/kg Al胁迫处理下,施加不同剂量的ZnO NPs(0、25、50、100和150 mg/kg),探究ZnO NPs对大豆生理指标(鲜质量、根长和叶绿素含量)、总超氧化物歧化酶(Total superoxide dismutase,T-SOD)活性和丙二醛(Malondialdehyde,MDA)浓度的影响。【结果】Al胁迫显著降低了‘华春6号’的鲜质量和根长,显著增加了其MDA浓度。对于‘华春2号’,Al胁迫显著增加了其叶绿素a和叶绿素b含量,而对其他指标无明显影响。无Al胁迫条件下施用ZnO NPs,均提高了‘华春6号’和‘华春2号’的鲜质量、根长和T-SOD活性。而在Al胁迫下施加不同剂量的ZnO NPs使‘华春6号’的鲜质量和根长分别增加13.2%~100.4%和7...  相似文献   
45.
采用静态吸附法研究Al2O3-P2O5-H2O反应体系产物三聚磷酸二氢铝Ⅰ型二水物[AlH2P3O10.2H2O(Ⅰ)]吸附水中Ni2+的动力学和热力学。考察了温度、浓度、粒径、pH和搅拌速度对吸附过程的影响,通过不同温度下的吸附等温热力学性能的变化,计算了吸附焓、吸附熵和自由能。结果表明,在试验范围内,AlH2P3O10.2H2O(Ⅰ)对Ni2+的吸附符合Langmuir吸附等温方程式,过程受颗粒扩散控制,反应级数为1.88,298.15 K时的热力学数据为:Ea=11.561 kJ/mol,ΔH=35.75 kJ/mol,ΔS=190.58 J/(mol.K),ΔG=-21.07 kJ/mol,吸附为自发的吸热过程,其吸附动力学总方程为:1-2/3x-(1-x)2/3=0.36r02C01.88exp(-11 561/RT)。  相似文献   
46.
A long-range transport model for East Asia was developed to estimate the wet deposition of sulfate. The model is a trajectory type which is appropriate for long-term analysis. Trajectories of air masses are calculated by tracing the wind field which changes spatially and temporally. The processes of reactions, rainout removal, intake of sulfate in cloud water into rain water, and dry and wet depositions are considered. It is possible to calculate the concentration of sulfate in precipitation at a receptor by performing material balance in a grid box containing the receptor.The results obtained by the long-range transport model were evaluated through comparison with observation data of acidic deposition. The observation was conducted at 21 stations throughout Japan for one year. The calculated amount of wet deposition of sulfate in Japan was 0.22Tg/y in S equivalent, while the observed amount was 0.29Tg/y. The long-range transport model can predict almost 80% of observed wet deposition. The contributions of domestic anthropogenic sources and volcanic eruption to wet deposition of sulfate in Japan were estimated using the longrange transport model. The ratio of the deposition of sulfate due to Japanese anthropogenic sources to that due to the Asian continental sources was about 1 to 2. Since air stream from the direction of the Asian continent dominates during winter, the contribution of Japan to wet deposition in the region which faces the Sea of Japan amounted to less than 15%. The contribution of the sulfur oxides from volcanoes was about 20%.  相似文献   
47.
矿物质调理剂中铝的稳定性及其对酸性土壤的改良作用   总被引:2,自引:0,他引:2  
蒙园园  石林 《土壤》2017,49(2):345-349
通过室内土壤培养试验和模拟酸雨浸泡试验,研究了3种含铝量不同的矿物质调理剂中铝的稳定性及其对酸性土壤的改良效果。该类调理剂是利用钾长石、白云石和石灰石等合理配伍后经高温焙烧而制得,呈弱碱性,富含有效钙、镁、钾、硅等营养元素。试验结果表明,施入0.5~2 g/kg调理剂培养60 d后,土壤pH由4.98升高到5.04~5.42,交换性铝含量下降37.40%~68.90%,吸附态羟基铝含量稍有增加,但毒害性铝和活性铝总量分别降低了5.37%~9.50%和4.33%~12.08%,提高土壤中交换性钙、镁、钾和有效硅的含量。同时模拟酸雨浸泡试验中铝溶出量明显降低。该类矿物质调理剂能中和土壤酸度、缓解铝毒和增加土壤养分;调理剂中铝稳定性较高,不会对土壤铝毒产生叠加效应,可安全应用于农业生产。  相似文献   
48.
This study clarified the origin of Al in spring water and stream water by analyzing the size distribution of Al of ground water, spring water, stream water, and soil extracts obtained by batch and column experiments using samples from a suburban secondary forest on granite bedrock in Aichi Prefecture. The high concentration of dissolved Al (Al0.45; fraction through 0.45-μm filter) in water samples obtained from this study site was divided into completely dissolved and small colloidal forms (<0.20 μm; Al0.20) and large colloidal forms (0.20–0.45 μm). More than 50% of dissolved Al (Al0.45) in spring water existed in large colloidal form. By comparing the size distribution and concentration of various elements including Al in the samples from soil batch and column experiments, we suggest that the high concentration of Al in spring water is caused by the release of Al from surface soils when ground water emerges as spring water.  相似文献   
49.
50.
[目的]研究铝(Ⅲ)-甲磺酸加替沙星荧光体系测定微量铝(Ⅲ)方法的建立与应用。[方法]在C6H4CO2HCO2K-NaOH介质中,铝与甲磺酸加替沙星形成络合物使甲磺酸加替沙星的荧光强度(ΔF)显著增敏,由此建立了测定铝的新方法,并研究不同溶液酸度、表面活性剂、甲磺酸加替沙星用量、试剂加入顺序对该体系ΔF的影响。[结果]荧光光谱图显示,该体系的最大激发波长λex=365 nm,最大发射波长λem=470 nm。溶液的酸度对该体系的ΔF有较大影响,pH值在5.50~6.50时可使该体系的增敏作用达到最大且较稳定。加入表面活性剂对ΔF均无较明显的影响。该体系中铝的浓度在1.58×10^-8~4.24×10^-6mol/L范围内与ΔF=F-F0具有良好的线性关系,最低检出限为8.36×10^-9mol/L,回收率为99.4%~101.4%。[结论]该方法用于测定食品中微量铝的含量可获得灵敏度较高和选择性较好的结果。  相似文献   
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