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1.
依次通过离子交换法、凝胶过滤法纯化重组白细胞介素-2(IL-2)粗品,利用SDS-PAGE电泳和hIL-2 Elisa kit检测纯化后重组IL-2的纯度和浓度。结果表明,纯化后的重组IL-2纯度和浓度高。本纯化方法简单、稳定、纯化效果好,可为重组IL-2的生产工艺提供技术支持和依据。 相似文献
2.
Fertilizer-induced Changes in Rhizosphere Electrical Conductivity: Relation to Forest Tree Seedling Root System Growth and Function 总被引:1,自引:0,他引:1
Fertilization is standard practice in forest tree seedling nursery culture. Additionally, fertilization at outplanting has potential to facilitate nutrient uptake and reduce transplant shock. Fertilization, however, may dramatically alter rhizosphere chemical properties such as pH, ion availability, and electrical conductivity (EC). These changes may inhibit root system growth and function by reducing soil osmotic potential and creating specific ion toxicities. The risk of root damage associated with high EC levels appears to be dependent on species, age of root system, and soil moisture availability. Root inhibition in container nursery culture of conifers is likely to occur above 2.5 dS m−1, though threshold EC levels for bareroot culture and field plantings are largely unavailable. Fertilization at outplanting has the added risk that drought conditions may prevent leaching of excess fertilizer salts, which can increase rhizosphere EC beyond safe levels and ultimately impair root uptake of water or nutrients. For fertilization programs to be successful, a critical threshold balance must be maintained between optimizing seedling nutrient availability in the rhizosphere, while minimizing potential for root damage. Future research is needed to identify optimal EC levels for a range of species across all stages of the reforestation process, from nursery culture through plantation establishment. 相似文献
3.
以柳树无性系SH31为试材,研究了NaCl溶液半抑制浓度胁迫下根、茎、叶中Na+、K+、Ca2+ 的分布规律及叶片光合特性的变化。结果表明:在NaCl溶液半抑制浓度(0.6%)下,SH31耐盐性较强;在0.6% NaCl溶液胁迫下,根部在前16 d积累大量Na+并拦截部分Na+向地上部运输;盐胁迫降低了根、茎部对 K+ 的吸收,而叶部却保持较高的K+ 含量来维持离子平衡;Ca2+含量在根、茎、叶中与对照的相当。在NaCl溶液半抑制浓度盐胁迫下,SH31 的净光合速率前7 d降低之后保持稳定,而气孔导度、蒸腾速率、胞间CO2先降后升,表明前7 d的蒸腾速率下降的主要原因在于气孔限制。SH31根部对Na+ 选择性吸收并维持K+、Ca2+的高含量及维持较高光合作用是其重要的耐盐机制。 相似文献
4.
[目的]同时测定潮州蔬菜汤中F-、Cl-、NO2-和NO3-的含量。[方法]利用WICⅡ-型离子色谱仪,测定潮州不同鲜度6种蔬菜汤中F-、Cl-、NO2-和NO3-的的含量。[结果]菜汤中NO3-的含量较高;菜汤中有适宜的F-、Cl-含量。[结论]保鲜处理放置的蔬菜中,NO2-、NO3-含量增加。 相似文献
5.
NaCl对库拉索芦荟的胁迫效应研究 总被引:12,自引:0,他引:12
温室盆栽条件下,研究了100~400mmol/L NaCl胁迫对2年生库拉索芦荟的生长及体内离子分布的影响。结果表明,100mmoL/L NaCl处理下芦荟植株干重和叶片叶绿素含量与对照差异不显著,200和400mmol/L NaCl处理下干重和叶绿素含量显著下降;芦荟根系活力在200mmol/L NaCl处理下达到最大值,增加盐浓度,根系活力下降;盐胁迫处理的叶片电解质渗漏率显著高于对照,随着胁迫强度的增加而增加。盐胁迫下,芦荟体内Na^+和Cl^-含量随着盐浓度的增加而增加,K^+和Ca^2+表现出相反的变化趋势。Na^+主要积累在茎部,叶片和根系含量较小;Cl^-主要积累在叶片,茎部含量相对高于根系。盐胁迫下芦荟体内K^+和Ca^2+含量明显低于对照,随着盐浓度增加,叶片K^+含量明显增加,Ca^2+则相反。芦荟叶片保持相对较低的Na^+/K^+比率和较强的K^+和Ca^2+向上选择性运输能力,是芦荟具有一定耐盐性的重要原因。 相似文献
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8.
低能离子注入麻黄种子生物效应初步研究 总被引:12,自引:0,他引:12
本文初步研究了离子束注入麻黄种子后的当代生物效应 ,研究表明 :离子注入对麻黄种子的生长起良好的生物效应。注入剂量为 4× 1 0 1 6 N+ / cm2 时 ,伊吾蓝麻黄种子发芽率最高为 76 % ,相对空白增长 4 3.4 % ;在注入剂量为 4× 1 0 1 6 N+ / cm2 ,伊吾蓝麻黄种子的发芽 3天时呼吸速率达 1 .1 4 0 mg/ g· h。这也表明发芽率高的剂量下 ,种子的呼吸速率增加 ,注入剂量为 1 2× 1 0 1 6 N+ / cm2 ,伊吾蓝麻黄种子的盆栽出土率最大为 2 2 .7%。 4× 1 0 1 6 N+ / cm2 剂量离子注入和硕蓝麻黄种子时 ,其盆栽出土率最大为 4 2 .3% ,比对照增加了 6 4 %。 相似文献
9.
Two plant species, tomato (Lycopersicon esculentum Mill.) and bitter gourd (Momordica charantia), were used for in‐depth studies on the dynamics of silicon (Si) uptake and translocation to the shoots and compartmentation of Si in the roots. The experiments were conducted under controlled environmental conditions in nutrient solutions, which were partly amended with 1 mM Si in the form of silicic acid. At harvest, xylem exudates were collected, and Si concentrations and biomass of roots and shoots were determined. Mass flow of Si was calculated based on the Si concentration of the nutrient solution and transpiration determined in a parallel experiment. Plant roots were subjected to a fractionated Si analysis, allowing attributing Si to different root compartments. Silicon concentrations in the roots compared to the shoots were higher in tomato but lower in bitter gourd. A more ready translocation from the roots to the shoots in bitter gourd was in agreement with Si concentrations in the xylem exudates which were higher than in the external solution. In tomato, the xylem‐sap Si concentration was lower than in the nutrient solution. Calculated Si mass flow to the root exceeded Si uptake in tomato, which was consistent with the measured accumulation of Si in the root water‐free space (WFS). In contrast, Si concentration in the root WFS was lower than in the nutrient solution in bitter gourd, reflecting the calculated Si depletion at the root surface based on the comparison of Si mass flow and Si uptake. Within the roots, more than 80% of the total Si was located in the cell wall and less than 10% in the cytoplasmic fractions in tomato. In bitter gourd, between 60% and 70% of the total root Si was attributed to the cell‐wall fraction whereas the proportion of the cytoplasmic fraction reached more than 30%. Our results clearly confirm that tomato belongs to the Si excluders and bitter gourd to the Si‐accumulator plant species for which high Si concentrations in the cytoplasmic root fraction appear to be characteristic. 相似文献
10.
半干旱地区海涂海水灌溉对不同品系菊芋产量构成及离子分布的影响 总被引:2,自引:0,他引:2
在半干旱海涂以不同品系菊芋(Helianthus tuberosusL.)为材料进行田间试验,研究了海水灌溉对不同品系菊芋产量构成及离子分布的影响。结果表明:(1)南芋2号根和地上部生物量较其他品系大,南芋5号和南芋3号株高在各浓度海水灌溉下均显著高于其他菊芋品系,而茎粗在各处理下变化不一致,在30%海水灌溉下,南芋1号根和地上部物质积累未受到抑制作用,其他各品系菊芋的根和地上部物质积累受到了一定抑制。(2)各菊芋品系块茎产量差异较显著,在30%海水灌溉下,南芋2号产量显著高于其他品系,各菊芋品系块茎单重在各处理下差异也较显著,南芋1号和2号块茎单重最大,各菊芋品系块茎总糖和菊糖含量差异较显著。(3)随海水浓度的增加,各品系菊芋根、茎和叶的C1-和Na^+含量均增加,但品系间差异较显著,叶片的Na’含量显著低于根和茎的Na’含量。从生物积累量和块茎产量、总糖和菊糖含量及离子分布看,南芋1号和南芋2号较其他品系更适合在半干旱海涂利用适当浓度海水进行灌溉种植。 相似文献