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101.
为建立一种快速的兔病毒性出血症病毒抗体检测方法,参照已发表的RHDV基因序列,采用RT-PCR扩增了长约510 bp的VP60基因片段,连接PGEX-4T-1表达载体后获得了以包涵体形式表达的重组VP60蛋白。重组蛋白纯化后,经免疫印迹检测证明具有良好的抗原性和特异性。以该蛋白作为诊断抗原,建立了检测兔病毒性出血症病毒抗体的VP60-ELISA诊断方法。该方法具有良好的敏感性、特异性和重复性,为RHDV的快速诊断、免疫兔群抗体监测和实验兔等级检测提供了一种快速、简便的血清学诊断方法。 相似文献
102.
Effect of collar insertion on soil respiration in a larch forest measured with a LI-6400 soil CO2 flux system 总被引:1,自引:0,他引:1
Wen Jie Wang Yuan Gang Zu Hui Mei Wang Takashi Hirano Kentaro Takagi Kaichiro Sasa Takayoshi Koike 《Journal of Forest Research》2005,10(1):57-60
Little information is available on the effect of root cutting by the collar pre-insertion technique on soil respiration. In this study, we found that soil respiration rates decreased with increasing depth of collar insertion in both the with live roots intact and with live roots severed treatments, but the rate of decrease was substantially higher in the former. The cutting of roots, especially fine roots, may be responsible for this result. 相似文献
103.
104.
1997年调查了长白山地区(Rhodiola sachalinensis)种子散布,发现高山红景天种子散布方向是不均匀的,以东部和西部最多。发芽试验的种子采自吉林省长白山和黑龙江省大海林迁地保护基地。种子采集后立刻用2%KNO3处理10小时、0.02%GA3处理5小时,结果显示迁地保护基地的高山红景天种子萌发率(85.33%)明显高于长白山(72.66%)。在0~5℃下贮存10个月之后,经上述不同浓度的激素处理,再测定发芽率。结果表明其发芽率为与刚采收时的发芽率(72.66%)差别不大,说明低温处理可明显延长种子寿命,同时发现,种子发芽率在一定程度上随激素浓度的增加而提高。图参9。 相似文献
105.
Distribution of solanesol in Nicotiana tabacum 总被引:1,自引:0,他引:1
Solanesol is an important secondary metabolite in Nicotiana tabacum. Distribution of solanesol in Nicotiana tabacum was investigated by High Performance Liquid Chromatography (HPLC) method. The quantitative distribution of solanesol in various organs and tissues of N. tabacum showed that solanesol content, obviously different in all organs, was 6.8, 18.3, 27.5, 45.8, and 68.0 times higher in leaves than that in the stalks, flowers, seeds, fruits and roots, respectively. The contents of solanesol in various parts of leaf, stalk and flower were determined. The content of solanesol in top leaf, middle leaf and bottom leaf gradually decreased (6.124, 5.813 and 5.687 mg.g^-1, respectively) and the content of solanesol in various leaf-parts (leaf apex, leaf middle and leaf base) also gradually decreased. The content of solanesol in top stalk was 1.19 times and 1.92 times higher than that in the middle stalk and the bottom stalk, respectively. The content of solanesol in various tissues of stalk (epidermis, cortex and stele) dramatically decreased. The sepal contained higher concentration of solanesol (1.192 mg·g^-1) compared to any other parts in flower. The study will provide the base data for the regulation and control of solanesol, moreover, it will provide the scientific evidences for the rational development and utilization of N. tabacum resources. 相似文献
106.
Wenjie Wang Huimei Wang Yuangang Zu Xueying Li Takayoshi Koike 《Frontiers of Forestry in China》2006,1(2):125-135
The temperature coefficient, Q
10 (fractional change in rate with a 10°C increase in temperature) describes the temperature sensitivity of soils, roots, and
stems, as well as their possible performance in global warming processes. It is also a necessary parameter for the estimation
of total CO2 efflux from each element. A number of studies have focused on Q
10 values to date; however, their conclusions are not universal and do not always agree. A review of these reported Q
10 values therefore becomes necessary and important for a global understanding of the temperature sensitivity of different forest
types and elements. The aims of our present paper are, first, to find the frequency distribution pattern of soils, roots,
and stems (branches) and compare their temperature sensitivity; then, to find the Q
10 differences between conifer and deciduous tree species and the effect of methodology on Q
10 values; finally we want to give a perspective on future Q
10-related studies. We found that most Q
10 values of each element were concentrated in a relatively narrow range despite a total data distribution over quite a wide
range. For soil respiration, the median Q
10 value was 2.74 and the center of the frequency distribution was between 2.0 and 2.5 with a percentage of 23%. Most of the
data (>80%) were within the range from 1.0 to 4.0. The median Q
10 value for root respiration was 2.40 and the center of the frequency distribution was from 2.5 to 3.0 with a percentage of
33%. Most of the results (>80%) ranged from 1.0 to 3.0. For stem respiration, the median Q
10 value was 1.91 and the frequency distribution was concentrated between 1.5 and 2.0. Over 90% of the data ranged from 1.0
to 3.0. Obvious differences in Q
10 value were found between different elements, stem < root < soil including root < soil excluding root. The differences between
woody organisms of stems, roots, and soils excluding roots were statistically significant (p<0.05), indicating that heterotrophic respiration from microorganism activity may be more sensitive to global warming. The
duration of the period with leaves slightly affects the temperature sensitivity of woody organisms since the Q
10 values for root and stem of coniferous evergreen trees did not differ significantly from deciduous trees (p>0.10). CO2 analytical methods (soda lime absorption method, IRGA (Infra-read gas analysis), and chromatograph analysis) and root separation
methods (excised root and trenched box) slightly affected the Q
10 values of soil and root respiration (p>0.10), but an in vitro measurement of stem respiration yielded a significantly higher Q
10 value than an in vivo method (p<0.05). In general, although the Q
10 values of non-photosynthetic organisms stayed within a relatively conservative range, considerable variation between and
within elements were still detectable. Accordingly, attention should be paid to the quantitative estimation of total CO2 efflux by Q
10-related models. In future studies, the biochemical factors and the environmental and biological factors controlling respiration
should be emphasized for precise estimation of total CO2 efflux. The difficulty is how to clarify the underlying mechanism for fluctuations of Q
10 values for one specific habitat and element (e.g. temperature acclimation or adaptation of Q
10 values) and then allow the Q
10 values to be more conservative for representation of temperature sensitivity in global warming processes.
__________
Translated from Acta Phytoecologica Sinica, 2005, 29(4) [译自:植物生态学报, 2005, 29 (4)] 相似文献
107.
Jizhong Wan Chunjing Wang Jinghua Yu Siming Nie Shijie Han Juzhao Liu Yuangang Zu Qinggui Wang 《林业研究》2016,27(2):389-400
We described potential changes in the geographic distribution and occurrence probability of Pinus koraiensis Sieb. et Zucc. and Eleutherococcus senticosus (Rupr. et Maxim.) Maxim. in the counties of northeast China. This information was used to identify priority areas for protection and provide protection and management recommendations within each studied county. The two species were mapped in 2884 study plots throughout this region over a 4-year period (38°40′N–53°30′N, 115°05′E–135°02′E). We used the species distribution models (Maxent), systematic conservation planning models (Marxan), and Geographic Information Systems (ArcGIS 10.0). The distributions of two species were correlated in the study area, enabling unique and economically viable joint conservation measures to be implemented. Three models were combined to identify feasible priority conservation sites. We used local spatial statistics to assess all identified conservation areas in relation to potential climate change based shifts in the geographic distribution of the two species. Model-based conservation strategies were used to identify effective measures to protect and utilize these two tree species in the study region. This study presents a novel technique for assessing wild plant distributions, in addition to serving as a model for the conservation of other species within the framework of general forest management, ecological construction, and geographical surveying. 相似文献
108.
Larch (Larix gmelinii (Rupr.) Rupr.) cone scales are green, but little is known of their photosynthetic role in cone development or about how they differ in gas exchange characteristics from needle leaves. In contrast to leaf photosynthesis (Pleaf), we found that stomatal regulation of cone photosynthetic rate (Pcone) was marginal because the photosynthetic carbon came from internal recycling of respiratory carbon dioxide (CO2). Photosynthetic recycling of respired CO2 was confirmed by the finding that the intercellular CO2 concentration (Ci) in cone scales was much higher than ambient [CO2]; also, there was a positive correlation between Pcone and Ci, whereas Pleaf was almost constant as Ci varied. Low chlorophyll (Chl) concentration was a limiting factor for Pcone, but not for Pleaf, as indicated by the correlation between Pcone and chlorophyll concentration. Moreover, chlorophyll utilization efficiency (Psat/Chl a+b) for cone scales was lower than that for leaves. In both cones and leaves, nitrogen (N) was positively correlated with photosynthetic capacity (P), but the P/N value was much lower for cones than for leaves. For both organs, the ratio of respiration to N was broadly similar. Although mature cones have no photosynthetic capacity, Pcone of young cones was as high as 5.3 micromol m(-2) s(-1), about 1.26 times the value of Pleaf, and accounted for the refixation of 30-40% of the respiratory CO2 produced by cones, equivalent to the photosynthetic capacity of a bundle of short shoots near each cone. Thus, Pcone may be an important additional source of photosynthate for cones, given the weak assimilating capacity of leaves that are not fully expanded during cone development. 相似文献
109.
采用室内模拟施肥、恒温振荡平衡法研究了磷肥种类、磷肥浓度、铅离子浓度、离子强度和酸度影响三峡库区消落带土壤对铅离子的吸附量和解吸量。结果表明:(1)磷肥种类与铅离子的吸附量和解吸量显著相关,施用Ca(H2PO4)2使铅离子的吸附量和解吸量相对较小;(2)土壤铅离子的吸附量和解吸量与施用磷肥浓度呈显著相关,建议选用磷酸二氢钙、磷酸二氢铵、磷酸二氢钾3种磷肥,施用量在3.4066~8.5164kg P2O5·666.6m-2之间较为合适;(3)铅离子浓度极显著地影响土壤吸附和解吸铅离子,随着铅离子浓度的增加,吸附量和解吸量都呈逐渐增加的趋势;(4)离子强度和酸度都极显著地影响土壤吸附和解吸铅离子,建议选用磷酸二氢钙盐、钾盐和铵盐作为磷肥,可以减小土壤铅离子的环境风险。 相似文献
110.