Using landscape and depth gradients to decouple the impact of correlated environmental variables on soil microbial community composition     

V.J. Allison  Z. Yermakov  R.M. Miller  J.D. Jastrow  R. Matamala 《Soil biology & biochemistry》2007,39(2):505-516

Simultaneously assessing shifts in microbial community composition along landscape and depth gradients allows us to decouple correlations among environmental variables, thus revealing underlying controls on microbial community composition. We examined how soil microbial community composition changed with depth and along a successional gradient of native prairie restoration. We predicted that carbon would be the primary control on both microbial biomass and community composition, and that deeper, low-carbon soils would be more similar to low-carbon agricultural soils than to high carbon remnant prairie soils. Soil microbial community composition was characterized using phospholipid fatty acid (PLFA) analysis, and explicitly linked to environmental data using structural equations modeling (SEM). We found that total microbial biomass declined strongly with depth, and increased with restoration age, and that changes in microbial biomass were largely attributable to changes in soil C and/or N concentrations, together with both direct and indirect impacts of root biomass and magnesium. Community composition also shifted with depth and age: the relative abundance of sulfate-reducing bacteria increased with both depth and restoration age, while gram-negative bacteria declined with depth and age. In contrast to prediction, deeper, low-C soils were more similar to high-C remnant prairie soils than to low-C agricultural soils, suggesting that carbon is not the primary control on soil microbial community composition. Instead, the effects of depth and restoration age on microbial community composition were mediated via changes in available phosphorus, exchangeable calcium, and soil water, together with a large undetermined effect of depth. Only by examining soil microbial community composition shifts across sites and down the soil column simultaneously were we able to tease apart the impact of these correlates environmental variables.  相似文献   

基于重组外膜蛋白P2的副猪嗜血杆菌抗体间接ELISA方法的建立   总被引：1，自引：0，他引：1  

李淼  李春玲  叶严锋  宋帅  杨冬霞 《华北农学报》2011,26(4):61-66

旨在建立一种基于重组副猪嗜血杆菌(HPS)外膜蛋白(Omp) P2的检测副猪嗜血杆菌抗体的间接ELISA方法.将重组表达的Omp P2纯化后作为ELISA包被抗原,建立了一种基于重组P2蛋白的间接ELISA方法,并对此方法的反应条件进行了优化.确定ELISA的最佳条件为:抗原包被浓度为1.5 μg/mL,被检血清1∶8...  相似文献   

抗谷胱甘肽-S-转移酶(GST)单克隆抗体的研制及初步应用     

滕蔓  罗俊  王秋霞  王丽  张改平 《华北农学报》2011,26(4):82-85

以纯化的谷胱甘肽转移酶标签蛋白(GST)免疫Balb/C小鼠,取免疫鼠脾细胞与NSO骨髓瘤细胞按常规方法融合,用纯化的GST经间接ELISA筛选,阳性孔经3次有限稀释法亚克隆,最终获得2株抗GST的单克隆杂交瘤细胞株,分别命名为4B7-F4和4B7-F4.间接ELISA检测4B7-E4、4B7-F4细胞培养上清的效价分...  相似文献   

山羊关节炎-脑炎ELISA方法的建立及其应用     

相文华  吕晓玲 《中国农业科学》1997,30(1):71-76

 应用间接酶联免疫吸附试验（ELISA），检测了山羊关节炎-脑炎病毒（CAEV）试验感染山羊和自然感染山羊的血清抗体，确定了最适宜的反应条件。CAEV感染山羊血清终点滴度结果表明：ELISA比琼脂扩散试验（ID）敏感性高，对自然感染山羊检出率比ID高3%左右。CAE标准阳性血清和自然感染阳性血清预先被特异性抗原中和后的ELISA反应均呈阴性，从而证实了本方法的特异性。因此，本方法适于CAE的流行病学调查和监测工作。  相似文献   

抗AIV(H9)独特型杂交瘤细胞株检测方法的建立   总被引：1，自引：1，他引：1  

彭军  李宝全  沈志勇  牛钟相 《西北农业学报》2005,14(4):132-134

采用兔抗AIV IgG作为检测抗原,通过预试确定了包被抗原的工作浓度为800μg／mL,以间接ELISA 方法检测融合细胞培养上清液,筛选到产生抗AIV鸡和兔种间共有独特型抗体的杂交瘤细胞,间接ELISA试 验中P／N值达12,证明杂交瘤细胞分泌目的单克隆抗体旱现强阳性。运用该检测方法,排除了分泌抗鸡同种 型表位以及超变区其他表位抗体的杂交瘤细胞,从而为筛选分泌抗H9亚型AIV独特型单克隆抗体的杂交瘤 细胞确定了可靠的方法。  相似文献   

诊断兔豆状囊尾蚴病的不同血清学检查方法的对比研究   总被引：2，自引：0，他引：2  

张守发  鞠玉琳  池鹤松 《延边大学农学学报》1995,(1)

本研究用兔豆状囊尾蚴的囊液作抗原，用皮内变态应、琼脂双向扩散试验、对流兔疫电泳、炭凝集试验、胶乳凝集试验和间接血凝试验，检测了兔三状囊尾蚴病的阳性血清及阴性血清．并分析、比较了各种方法在诊断兔豆状囊尾蚴病的应用效果和价值．结果问接血凝试验的效果最好，其次是胶乳凝集试验、炭凝集试验．但三种方法检测效果差异不显著，都具有简便、早期、快速、敏感、准确等优点，均可在现地推广使用．而皮内变态反应、琼脂双向扩散试验、对流兔疫电泳的检出率低，不适合用于兔豆状囊尾蚴病的免疫学诊断．  相似文献   

异步电机效率测试误差的分析计算     

赵龙章  孙贵根 《扬州大学学报(农业与生命科学版)》1992,(1)

用间接测量法分析了异步电动机效率测试的随机误差规律,研究了效率测试误差区域的计算方法,并作了实测计算例证。  相似文献   

应用间接血凝试验检测牛肺疫抗体     

马学恩  郭景芳 《内蒙古农业大学学报(自然科学版)》1989,10(1):42-48

自制1.5％绵羊红细胞诊断液并用于检测牛肺疫抗体,结果如下:(一)三批标准阳性血清(批号为8601、8301、8001)凝集价均在160倍以上,标准阴性血清(批号为8601)凝集度仅为10倍。15份被检血清IHA的阳性检出率(8/15)高于补体结合反应(CF,6/15)且凝集价均在40倍以上。(二)用牛肝片吸虫病、布氏杆菌病和附红细胞体病阳性血清作类症鉴别诊断,凝集度仅为10倍。(三)把牛肺疫CF8502抗原作倍比稀释,加2个凝集单位牛肺疫阳性血清8601和8301进行间接血凝抑制试验,分别被32倍和16倍稀释的抗原所抑制,本项试验结果表明IHA用于检测牛肺疫,具有检出率高、特异性强、设备要求简单、容易操作等特点,适于在现地推广应用。  相似文献   

一种快速检测抗沙门氏菌O抗原单克隆抗体的微量间接血凝试验     

甘军纪  张如宽  刘秀梵 《扬州大学学报(农业与生命科学版)》1988,(2)

用热酚—水法提取沙门氏菌脂多糖(LPS),经pH8.0热处理后,致敏醛化的绵羊红血球,建立了一种快速检测抗沙门氏菌O抗原单克隆抗体的微量间接血凝试验。用致敏血球在96孔V型血凝板上与杂交瘤培养上清作凝集试验,数秒钟即能判定结果。本试验具有快速的特点,且有一定的敏感性。  相似文献   

Protected wading bird species threaten relict centenarian cork oaks in a Mediterranean Biosphere Reserve: A conservation management conflict     

Luis V. García  Cristina Ramo  Cristina Aponte  Adela Moreno  María T. Domínguez  Lorena Gómez-Aparicio  Ramón Redondo  Teodoro Marañón 《Biological conservation》2011,(2):764-771

Conservation management conflicts frequently arise when an overpopulation of a protected organism has negative effects on other valuable elements in the same ecosystem. We studied the interactions between a colony of protected tree-nesting wading birds and a remnant population of centenarian cork oaks that was part of the formerly dominant forests in the Doñana Biological Reserve (SW Spain). A significant increase in the tree mortality rates has been recorded in areas that are yearly influenced by the bird colony.We analysed a cohort of surviving trees using a gradient of nesting bird influence. Tree-nesting history, bird isotopic signature (δ¹⁵N), tree health-related parameters (defoliation, δ¹³C and leaf surface coverage by faeces) and several soil variables were evaluated. Bird influence was related to increased soil salinity. This increase correlated to increased water-use efficiency for the leaves and to crown defoliation, suggesting that the heavily occupied trees are under higher stress and in poorer health condition than the unoccupied ones. We tested structural equations models (SEM) that were based on hypothesised bird effects on the health of the trees. Soil-mediated effects of the nesting birds best explained the symptoms of the declining health of the trees, whereas the percent of leaves’ surface that was covered by faeces did not improve the fitted SEM model.For the reserve’s managers, a challenging trade-off exists between preserving the relict trees, which have a high genetic diversity and a key ecological role in these savannah-like ecosystems, and maintaining the current nesting area for these protected, but expanding, wading birds.  相似文献