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21.
Lô-Pelzer E. Aubertot J. N. Bousset L. Pinochet X. Jeuffroy M. H. 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(4):515-522
Several disease indices (DI) have been proposed to assess the severity of phoma stem canker at late growth stages. The DI
commonly used in France (called G2 DI) consists of integrating the distribution of the proportions of plants observed within six canker severity classes into
a single index. This index uses arbitrarily chosen coefficients associated to each class of canker severity. A given value
of this DI can therefore be obtained with different distributions among the canker severity classes. Consequently, it is important
to assess to what extent the G2 DI is representative of the distribution of plants in canker severity classes. We show in this study that the G2 DI is a good indicator of the distribution of the observed canker severities, using a dataset from different years, sites
and cultivars; this illustrates the robustness of the G2 DI. 相似文献
22.
In this study salt-free dyeing cotton fabric was achieved by grafting thiourea to cotton fibers, where the thiourea grafted
cotton fabric (TUGCF) was prepared by epoxidizing cotton fibers with epichlorohydrin in water and subsequently grafting in
aqueous solution of thiourea. Fourier transform infrared spectra (FTIR) and XPS of the TUGCF indicated that a great amount
of epoxy groups from the epoxidized cotton fibers reacted with amino groups from thiourea. The TUGCF fabric prepared at the
optimum condition and subsequently dyed with reactive dyes in the absence of salt displayed significantly enhanced color strength,
showing better dyeing properties when compared with the untreated cotton fabric dyed with conventional methods, in terms of
washing fastness, rubbing fastness, and levelness. It was found that the dyeing performance of Reactive Red B-3BF followed
a Langmuir-type adsorption curve when used to salt-free dye the TUGCF. 相似文献
23.
In this study the effects of growth hormone (GH) on silver sea bream branchial heat-shock protein 70 (HSP70) expression was
investigated using in-vivo and in-vitro experiments. For in-vivo experiments, sea bream were administered recombinant bream
GH or the GH secretagogue hexarelin. Pituitary levels of GH were unchanged in fish administered exogenous GH but decreased
on hexarelin administration, in comparison with saline controls. Levels of HSP70 were measured using immunoanalysis and it
was found that both GH and hexarelin administration caused a significant decrease in branchial HSP70 abundance. For in-vitro
analysis, branchial filaments were exposed to a range of GH concentrations (1, 10, and 100 ng/ml) and it was found that HSP70
levels were significantly lowered in all cases. This study adds to the growing body of evidence surrounding the importance
of hormones in regulating heat-shock protein expression in fish. 相似文献
24.
Andreas Kofoet Mathias Fink 《European journal of plant pathology / European Foundation for Plant Pathology》2007,117(4):369-381
Epidemics of Peronospora parasitica are strongly affected by temperature and air moisture, and the interaction of these factors. Because a significant percentage
of radish plants are grown in greenhouses, it may be possible to influence epidemics by altering the greenhouse climate. The
objective of this study was to test the hypothesis that epidemics of P. parasitica can be modelled by the effects of air temperature and moisture in the greenhouse. Such a model could then be used to analyse
greenhouse climate control strategies with regard to managing downy mildew. Five radish crops were grown under greenhouse
conditions with set-points for heating and ventilation intended to obtain favourable conditions for disease development during
the first part of the growing cycle. Subsequent to this first phase, unfavourable conditions were set until harvest. Disease
incidence was measured once a week until the radishes reached marketable size. In addition, experiments were carried out in
growth chambers in which inoculated plants were subjected to air temperatures between 8 and 27°C, and disease incidence and
sporulation intensity were measured. Data from these two experiments were then used to estimate model parameters. In this
model, the interactions of air temperature (T) and water vapour saturation deficit (SD) were adequately described by a multiplicative
relationship. The simulated epidemics by the fitted model were highly correlated with the observed epidemics (r = 0.91, R
2 = 0.83, n = 29). Parameter estimates indicated that T of ca. 20°C and SD < 0.03 hPa resulted in the highest rates of disease development
and that the rate was zero when SD > 2.0 hPa. Both experimental data and simulations showed that epidemics of P. parasitica can be effectively controlled by managing the greenhouse climate. 相似文献
25.
A study was conducted to assess the role and effectiveness of community organisers in supporting the development of people’s
organisations in achieving community-based forest management objectives in Leyte Province Philippines. Community organisers
were found to be effective in forming people’s organisations (POs), motivating people to participate in voluntary activities
organised by POs and encouraging cohesiveness among PO members. Community organisers manage to raise the level of environmental
awareness and knowledge of members of people’s organisations, develop leadership interest and skills, create various livelihood
opportunities and provide direction and facilitate the establishment of large tree plantations. However, the short duration
of community organisers’ contracts (typically two years) is insufficient to establish mature and cohesive POs prepared to
assume management on their own, including the management of tree plantations. Further, lack of training and funding support,
low wages, delayed payment of salaries and limited time to work with people’s organisations, as well as the pressure to produce
tangible outputs such the establishment of large tree plantations, prevents them from placing greater emphasis on the development
and empowerment of the people. 相似文献
26.
ABSTRACT: Thermal limits, induced thermotolerance and the expression of heat shock protein 70 (Hsp70) in an echinoderm Apostichopus japonicus were studied. The sublethal and lethal temperatures for the juveniles were 30 and 34°C, respectively; a previous sublethal heat shock exposure (30°C, 2 h) could increase the survival rates of the sea cucumbers when they were exposed to 34°C. This induced thermotolerance could last for at least 2 days. Levels of Hsp70 increased substantially after sublethal heat shock exposure and linearly decreased with time. This result indicated that a close relationship existed between the induction of thermotolerance and the levels of Hsp70 in A. japonicus. 相似文献
27.
Mario A. Burgos-Aceves Rafael Campos-Ramos Danitzia A. Guerrero-Tortolero 《Fish physiology and biochemistry》2010,36(4):1263-1269
The peripheral blood cells and differential blood profile of captive female and male leopard grouper Mycteroperca
rosacea are described for aquacultural purposes. Basophilic, polychromatic, and orthochromic erythroblasts were observed as immature
erythrocytes that develop into mature erythrocytes. Young erythrocytes were not evident, and bi-lobed erythrocytes were extremely
scarce. Types of leukocytes included lymphocytes; three types of granulocytes (basophiles, eosinophiles, and neutrophiles);
monocytes; and a specialized amoeboid-like macrophage in the blood, which has not been previously described in fish-blood
literature. Thrombocytes were commonly observed. There was significantly higher erythropoiesis in males. Granulocytes and
lymphocytes of females were significantly higher than males, whereas monocytes and thrombocytes were not. 相似文献
28.
Wenming Ma Zhongwu Li Keyi Ding Bin Huang Xiaodong Nie Yinmei Lu Haibin Xiao Guangming Zeng 《Journal of Soils and Sediments》2016,16(6):1705-1717
Purpose
This study aims to explore the dynamics of the factors influencing soil organic carbon (SOC) sequestration and stability at erosion and deposition sites.Materials and methods
Thermal properties and dissolved aromatic carbon concentration along with Al, Fe concentration and soil specific surface area (SSA) were studied to 1 meter depth at two contrasting sites.Results and discussion
Fe, Al concentrations and SSA size increased with depth and were negatively correlated with SOC concentration at the erosion site (P?<?0.05), while at the deposition site, these values decreased with increasing depth and were positively correlated with SOC concentration (P?<?0.05). TG mass loss showed that SOC components in the two contrasting sites were similar, but the soils in deposition site contained a larger proportion of labile organic carbon and smaller quantities of stable organic carbon compared to the erosion site. SOC stability increased with soil depth at the erosion site. However, it was slightly variable in the depositional zone. Changes in SUVA254 spectroscopy values indicated that aromatic moieties of DOC at the erosion site were more concentrated in the superficial soil layer (0–20 cm), but at the deposition site they changed little with depth and the SUVA254 values less than those at the erosion site.Conclusions
Though large amounts of SOC accumulated in the deposition site, SOC may be vulnerable to severe losses if environmental conditions become more favorable for mineralization in the future due to accretion of more labile carbon. Deep soil layers at the erosion site (>30 cm deep) had a large carbon sink potential.29.
The ecology and culture of landscape sustainability: emerging knowledge and innovation in landscape research and practice 总被引:3,自引:1,他引:3
Laura R. Musacchio 《Landscape Ecology》2009,24(8):989-992
Landscape researchers and practitioners, using the lens of sustainability science, are breaking new ground about how people’s
behaviors and actions influence the structure, function, and change of designed landscapes in an urbanizing world. The phrase—the
scientific basis of the design for landscape sustainability—is used to describe how sustainability science can contribute
to translational landscape research and practice about the systemic relationships among landscape sustainability, people’s
contact with nature, and complex place-based problems. In the first section of this article, important definitions about the
scientific basis of the design for landscape sustainability are reviewed including the six Es of landscape sustainability—environment, economic, equity, aesthetics, experience, and ethics. A conceptual framework about the six Es of landscape sustainability for designed landscapes is introduced. The interrelatedness,
opportunities, contradictions, and limitations of the conceptual framework are discussed in relation to human health/security,
ecosystem services, biodiversity, and resource management. The conceptual framework about the six Es of landscape sustainability
for designed landscapes follows the tradition in which landscape researchers and practitioners synthesize emerging trends
into conceptual frameworks for advancing basic and applied activities. 相似文献
30.
Socio-economic significance of reed forests in a rural community: A case study from the greater Sylhet Region of Bangladesh 总被引:1,自引:0,他引:1
Qumruzzaman Chowdhury A. Z. M. Manzoor Rashid Masuduzzaman Afrad 《Small-Scale Forestry》2004,3(1):121-130
The reed forests that are the subject of this study are scattered over five thanas of the Sunamganj and Sylhet Districts of
the Sylhet Division of Bangladesh. Their total area is 23,590 ha and they have great ecological, economic, commercial and
socio-economic importance due to the diversified resources they supply. However, the forests are commonly encroached on by
local people who are perceived to be seriously depleting the resource. This paper deals with the socio-economic status of
the people residing near these reed forests, and examines their dependency on the resources provided by the reed forests.
A socio-economic survey, participatory rural appraisal and interviews were used to obtain baseline data of the reed forest
resource and the local communities. The study reveals that the communities in the study region have higher income than other
areas of Bangladesh. Most survey respondents have other occupations in addition to farming. The literacy rate is 28.8%. Among
the illiterate, 68% engage in collecting reeds. Although the Forest Department has a management plan for sustainable use of
the reed forests, encroachers receive backing from political leaders and local elites, so their eviction is difficult. In
order to achieve long-term productivity and sustainability from the reed forests, this study recommends a strategy of developing
an integrated joint management plan between the Forest Department and the local people. 相似文献