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Genetic identification and reiterated captures suggest that the Astyanax mexicanus El Pachón cavefish population is closed and declining
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作者 Laurent Legendre Julie Rode +11 位作者 Isabelle Germon Marie Pavie Carla Quiviger Maxime Policarpo Julien Leclercq Stéphane Père Julien Fumey Carole Hyacinthe Patricia Ornelas-García Luis Espinasa Sylvie Rétaux Didier Casane 《Zoological Research》 SCIE CSCD 2023年第4期701-711,共11页
The sizes of Astyanax mexicanus blind cavefish populations of North-East Mexico are demographic parameters of great importance for investigating a variety of ecological,evolutionary,and conservation issues.However,few... The sizes of Astyanax mexicanus blind cavefish populations of North-East Mexico are demographic parameters of great importance for investigating a variety of ecological,evolutionary,and conservation issues.However,few estimates have been obtained.For these mobile animals living in an environment difficult to explore as a whole,methods based on capture-mark-recapture are appropriate,but their feasibility and interpretation of results depend on several assumptions that must be carefully examined.Here,we provide evidence that minimally invasive genetic identification from captures at different time intervals(three days and three years)can give insights into cavefish population size dynamics as well as other important demographic parameters of interest.We also provide tools to calibrate sampling and genotyping efforts necessary to reach a given level of precision.Our results suggest that the El Pachón cave population is currently very small,of an order of magnitude of a few hundreds of individuals,and is distributed in a relatively isolated area.The probable decline in population size in the El Pachón cave since the last census in 1971 raises serious conservation issues. 展开更多
关键词 CAVEFISH Population size Conservation SWABBING Genetic identification
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稻曲病不同抗性水稻品种的组织化学及分生孢子侵染途径的初步观察 被引量:12
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作者 代光辉 赵杰 +2 位作者 何润梅 金素心 M.NICOLE 《植物病理学报》 CAS CSCD 北大核心 2005年第1期37-42,共6页
用稻曲病菌分生孢子悬浮液对抽穗期水稻进行接种,观察分生孢子及其侵染途径。结果发现,分生孢子在颖壳表面可萌发形成菌丝,在颖口内侧可以见到菌丝伸向谷颖内部,可能为分生孢子直接侵染稻穗提供了一定证据。对抗、感品种谷粒的组织化学... 用稻曲病菌分生孢子悬浮液对抽穗期水稻进行接种,观察分生孢子及其侵染途径。结果发现,分生孢子在颖壳表面可萌发形成菌丝,在颖口内侧可以见到菌丝伸向谷颖内部,可能为分生孢子直接侵染稻穗提供了一定证据。对抗、感品种谷粒的组织化学研究结果表明:抗病品种的颖壳中含有大量的木质素,感病品种中的木质素较少;在抗病品种谷粒的颖壳中的红色荧光物质远远多于感病品种;在抗病品种谷粒表皮的胚乳细胞中也含有多酚类物质,这层细胞较正常细胞大,在感病品种中没有发现。稻曲球切片的紫外光观察可发现每一个稻曲球中存在 6个“蝴蝶”型荧光结构,染色剂染色后观察证明该结构不含过氧化物酶、单宁类物质、木栓质和木质素。 展开更多
关键词 分生孢子 侵染途径 组织化学 抗性水稻品种 抗病品种 感病品种 孢子悬浮液 多酚类物质 过氧化物酶 木质素 稻曲病菌 研究结果 荧光物质 胚乳细胞 正常细胞 抽穗期 颖壳 谷粒 紫外光 染色剂 菌丝 结构 接种 稻穗
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三种中草药植物和葡萄籽中的白藜芦醇分析(英文) 被引量:7
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作者 姚柳利 代光辉 +4 位作者 刘玉敏 陶萍 C.Andary M.Nicole 蒋水元 《上海交通大学学报(农业科学版)》 2005年第1期31-35,45,共6页
通过气质和液质联用技术,对三种中草药植物虎杖、买麻藤和小叶买麻藤以及葡萄籽中白藜芦醇首先进行了定性研究;而后采用高压液相法对这四种植物的提纯液进行了定量研究,含量分别为53.00,36.18,32.69和30.63μg·g-1;其次对小叶买麻... 通过气质和液质联用技术,对三种中草药植物虎杖、买麻藤和小叶买麻藤以及葡萄籽中白藜芦醇首先进行了定性研究;而后采用高压液相法对这四种植物的提纯液进行了定量研究,含量分别为53.00,36.18,32.69和30.63μg·g-1;其次对小叶买麻藤的藤茎进行了组织化学的定位研究,发现白藜芦醇在韧皮部中的含量为448.80μg·g-1,在木质部中为0μg·g-1,结果显示白藜芦醇主要存在于韧皮部中。 展开更多
关键词 白藜芦醇 中草药 葡萄籽 含量 高压液相 虎杖 组织化学 植物 韧皮部 种植
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珠江下游颗粒沟链藻Aulacoseira granulata (Ehrenberg) Simonsen及形态相近种赫组基沟链藻Aulacoseira herzogii (Lemmerman) Simonsen的形态学研究 被引量:3
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作者 李维薇 孙金辉 +1 位作者 王超 Loic Tudesque 《植物科学学报》 CAS CSCD 北大核心 2018年第2期221-228,共8页
采用扫描电镜(SEM)技术,对采自珠江下游的沟链藻属2个物种颗粒沟链藻Aulacoseira granulata(Ehrenberg)Simonsen和赫组基沟链藻A.herzogii(Lemmerman)Simonsen的形态特征进行了观察和描述,并与其他相近种的形态异同点进行了比较分析。
关键词 沟链藻属 分裂刺 形态分类学 珠江
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High-temperature granulites and supercontinents 被引量:4
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作者 J.L.R.Touret M.Santosh J.M.Huizenga 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第1期101-113,共13页
The formation of continents involves a combination of magmatic and metamorphic processes. These processes become indistinguishable at the crust-mantle interface, where the pressure-temperature(P-T)conditions of(ul... The formation of continents involves a combination of magmatic and metamorphic processes. These processes become indistinguishable at the crust-mantle interface, where the pressure-temperature(P-T)conditions of(ultra) high-temperature granulites and magmatic rocks are similar. Continents grow laterally, by magmatic activity above oceanic subduction zones(high-pressure metamorphic setting), and vertically by accumulation of mantle-derived magmas at the base of the crust(high-temperature metamorphic setting). Both events are separated from each other in time; the vertical accretion postdating lateral growth by several tens of millions of years. Fluid inclusion data indicate that during the high-temperature metamorphic episode the granulite lower crust is invaded by large amounts of low H2O-activity fluids including high-density CO2 and concentrated saline solutions(brines). These fluids are expelled from the lower crust to higher crustal levels at the end of the high-grade metamorphic event. The final amalgamation of supercontinents corresponds to episodes of ultra-high temperature metamorphism involving large-scale accumulation of these low-water activity fluids in the lower crust.This accumulation causes tectonic instability, which together with the heat input from the subcontinental lithospheric mantle, leads to the disruption of supercontinents. Thus, the fragmentation of a supercontinent is already programmed at the time of its amalgamation. 展开更多
关键词 CONTINENTS SUPERCONTINENTS Magmatism and metamorphism Fluids TECTONICS
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From granulite fluids to quartz-carbonate megashear zones:The gold rush 被引量:9
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作者 Bin Fu Jacques L.R.Touret 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第5期747-758,共12页
At peak granulite-facies metamorphic conditions, lower continental crust is arguably fluxed by large amounts of two key low water activity fluids: (i) high-density CO2 and/or (ii) concentrated saline so- lutions.... At peak granulite-facies metamorphic conditions, lower continental crust is arguably fluxed by large amounts of two key low water activity fluids: (i) high-density CO2 and/or (ii) concentrated saline so- lutions. These fluids are either internally-derived, generated by mineral reactions or dehydration melting or, notably for CO2, externally-derived, issued from the underlying mantle. Postmetamorphic evolution results in complete disappearance of these fluids, except for minute remnants preserved in minerals as fluid inclusions. Two major processes are involved: (i) at peak conditions, granitoid magmas form, migrate upward, and crystallize as shallow intrusions in the upper crust (mineralized porphyry types or reduced intrusions); (ii) during the rapid decompression which almost systematically follows a period of post-peak isobaric cooling, especially for ultrahigh-temperature granulites (anticlockwise P-T paths), quartz-carbonate megashear zones are formed by repeated periods of seismic activity. Seismic activity may continue until all free fluids have disappeared, resulting in the ultramylonites and pseudotachylites that are found in many granulite domes. A great majority of vein-type Au deposits worldwide occur in the above-mentioned settings or nearby. We suggest that the Au has been scavenged by the granulite fluids, then redistributed and concentrated during the formation of veins and related phenomena. 展开更多
关键词 Granulite CO2 BrinesMegashear zonesAu mineralization
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How everything started:A retrospective 被引量:1
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作者 Jacques Touret 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第5期627-634,共8页
Recalling some of the most important events and persons during his education and career, the author sketches his growth from a young engineer, educated in the sanctuary of solid state reactions, to an involved fully d... Recalling some of the most important events and persons during his education and career, the author sketches his growth from a young engineer, educated in the sanctuary of solid state reactions, to an involved fully devoted scientific career for the study of fluids in the deep Earth. Most important in this respect was the discovery of C02 inclusions in granulites, which triggered years of discussion on fluid- absent or fluid-assisted granulite metamorphism. To some extent, this debate is a continuation of the former granite controversy, but it shows also how the famous battle of "soaks against pontiffs" could have been easily avoided. 展开更多
关键词 Granite controversyMetamorphic petrologyFluid inclusionsJ TouretGranulites
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Geofluids:Developments in Microthermometry,Spectroscopy,Thermodynamics and Stable Isotopes 被引量:1
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作者 V.Hurai M.Huraiovà +2 位作者 M.Slobodnik R.Thomas Jacques Touret 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第1期151-151,共1页
Fluid (and melt) inclusion studies have shown a marked devel- opment in the last decades, as indicated by the increasing number of papers and as covered under major themes in specialized meetings (e.g. ECROFI in Eu... Fluid (and melt) inclusion studies have shown a marked devel- opment in the last decades, as indicated by the increasing number of papers and as covered under major themes in specialized meetings (e.g. ECROFI in Europe, PACROFI in America, ACROFI in Asia). However, a basic text book is lacking in current literature, available information being either somewhat outdated (e,g. Roedder, 1984) or scattered in multi-author "short course", mainly organized by the Mineralogical Societies of Canada, America or Europe. A result is that basic features of fluid inclusion studies, notably its key technique, microthermometry, and recently supplemented by micro Raman of infrared spectroscopy, is rarely taught in most universities, leaving the student alone to discover a field of study which has grown to the dimensions of a major science. 展开更多
关键词 Geofluids Spectroscopy Thermodynamics and Stable Isotopes
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The Effect of Four Abiotic Factors on Macro-Anatomical Markers Development in <i>Parkia biglobosa</i>, Jack, R. Br., 1830 (Fabaceae) Crown 被引量:1
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作者 Beda Innocent Adji Doffou Sélastique Akaffou +3 位作者 Kouadio Henri Kouassi Yao Patrice Houphouet Jerôme Duminil Sylvie Sabatier 《American Journal of Plant Sciences》 2021年第4期645-661,共17页
Interpretation of primary growth markers (modules) is neglected in sustainable resource management processes, yet it opens up prospects for long time series on tree crown development, necessary for their characterizat... Interpretation of primary growth markers (modules) is neglected in sustainable resource management processes, yet it opens up prospects for long time series on tree crown development, necessary for their characterization in the current context of climate change. This study aimed to assess the morphological variation of crown shoots in <i><span style="font-family:Verdana;">Parkia biglobosa</span></i><span style="font-family:Verdana;"> in the face of a changing environment. Axis growth modules of 420 individuals of different ages were retrospectively analyzed in the presence or absence of shading during the wet and dry seasons in seven localities in Cote d’Ivoire. The results showed that the developmental environment of individuals did not influence the growth modules dimensions (P > 0.05). However, module size remained significantly different between locations (P < 0.05). The southern part of the gradient is still favourable and has priority for the establishment of permanent plots. The modules morphology differs from the youngest to the oldest individuals (P < 0.05). The rainy season remains the ideal period for the implementation of agroforestry reforestation programmes based on this species (P < 0.05). </span><i><span style="font-family:Verdana;">Parkia biglobosa</span></i><span style="font-family:Verdana;"> is a monochasial sympod (Pseudo-monopod) with a relay axis that follows the Paul Champagnat architectural model in the young stage, and transits to the Wilhelm Troll model later in the adult and old stage. This information contributes to the understanding of the functioning of crown and the adaptation of this species to a varying environment. It could guide choice of suitable environment and ideal genotype for the implementation of a reforestation or agroforestry programme based on </span><i><span style="font-family:Verdana;">Parkia biglobosa</span></i><span style="font-family:Verdana;">.</span> 展开更多
关键词 Parkia biglobosa Environment DEVELOPMENT Growth Modules CROWN
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Fluid-rock interaction in retrograde granulites of the Southern Marginal Zone,Limpopo high grade terrain,South Africa 被引量:2
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作者 Jan Marten Huizenga Dirk van Reenen Jacques L.R.Touret 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第5期673-682,共10页
Fluid infiltration into retrograde granulites of the Southern Marginal Zone (Limpopo high grade terrain) is exemplified by hydration reactions, shear zone hosted metasomatism, and lode gold mineralisation. Hydration... Fluid infiltration into retrograde granulites of the Southern Marginal Zone (Limpopo high grade terrain) is exemplified by hydration reactions, shear zone hosted metasomatism, and lode gold mineralisation. Hydration reactions include the breakdown of cordierite and orthopyroxene to gedrite + kyanite, and anthophyllite, respectively. Metamorphic petrology, fluid inclusions, and field data indicate that a low H2O-activity carbon-saturated CO2-rich and a saline aqueous fluid infiltrated the Southern Marginal Zone during exhumation. The formation of anthophyllite after orthopyroxene established a regional retrograde anthophyllite-in isograd and occurred at P-Tconditions of -6 kbar and 610 ℃, which fixes the minimum mole fraction of H20 in the CO2-rich fluid phase at ~ 0.1. The maximum H20 mole fraction is fixed by the lower temperature limit (~800 ℃) for partial melting at -0.3. C-O-H fluid calculations show that the CO2-rich fluid had an oxygen fugacity that was 0.6 log10 units higher than that of the fayalite-magnetite- quartz buffer and that the CO2/(CO2+CH4) mole ratio of this fluid was 1. The presence of dominantly relatively low density CO2-rich fluid inclusions in the hydrated granulites indicates that the fluid pressure was less than the lithostatic pressure. This can be explained by strike slip faulting and/or an increase of the rock permeability caused by hydration reactions. 展开更多
关键词 GranuliteFluidLimpopoRetrogradeSouthern Marginal Zone
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Response of Soil Microbial Properties to Long-Term Application of Organic and Inorganic Amendments in a Tropical Soil (Saria, Burkina Faso) 被引量:1
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作者 Ndeye Hélène Diallo-Diagne Komi Assigbetse +4 位作者 Saïdou Sall Dominique Masse Moussa Bonzi Ibrahima Ndoye Jean Luc Chotte 《Open Journal of Soil Science》 2016年第2期21-33,共13页
Soil microbial biomass carbon (MBC), β-glucosidase, acid phosphatase and fluorescein diacetate (FDA) activities and bacterial community structure were assessed in a long-term (26 years) experiment, at physiological s... Soil microbial biomass carbon (MBC), β-glucosidase, acid phosphatase and fluorescein diacetate (FDA) activities and bacterial community structure were assessed in a long-term (26 years) experiment, at physiological stages of sorghum growth, comparing different management methods for organic (manure, straw residues) and inorganic (urea) amendments at the INERA field station in Saria (Burkina Faso). Annual application of manure led to the highest soil microbial biomass and enzyme activities. Investigations indicated that only microbial biomass and β-glucosidase activities were affected during the cropping season. Phosphatase and FDA enzyme activities did not depend on the crop development stages. The application of N fertilizer modified phosphatase and FDA enzyme activities, the activities being higher in soils amended with N fertilizer. The bacterial community structure was analyzed by PCR-denaturing gradient gel electrophoresis (PCR-DGGE) targeting the eubacterial 16S rRNA gene. Cluster analysis of PCR-DGGE patterns showed two major clusters, the first containing the mineral fertilization and straw treatments and the second, the straw + urea, manure and manure + urea treatments. Sorghum grain yields were the highest for manure treatments. In this long-term experiment, applying straw did not produce a better grain yield than that obtained in the un-amended plot. 展开更多
关键词 Organic Amendments Mineral Fertilizer Microbial Biomass Soil Enzyme Activities PCR-DGGE Crop Development Stages Lixisol
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Field Application of the Mycorrhizal Fungus <i>Rhizophagus irregularis</i>Increases the Yield of Wheat Crop and Affects Soil Microbial Functionalities 被引量:1
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作者 Sanaa Wahbi Yves Prin +5 位作者 Tasnime Maghraoui Hervé Sanguin Jean Thioulouse Khalid Oufdou Mohamed Hafidi Robin Duponnois 《American Journal of Plant Sciences》 2015年第19期3205-3215,共11页
The aim of this study was to test the impact of Rhizophagus irregularis, an arbuscular mycorrhizal fungus (AMF), on durum wheat growth and soil microbial functionalities in a field inoculation trial conducted in Moroc... The aim of this study was to test the impact of Rhizophagus irregularis, an arbuscular mycorrhizal fungus (AMF), on durum wheat growth and soil microbial functionalities in a field inoculation trial conducted in Morocco. The results showed that i) the R. irregularis inoculum effectively improved wheat growth, ii) wheat growth promotion depended on the soil mycorrhizal infectivity and iii) functional abilities of soil microflora depended on AMF inoculation. This study confirms that field AMF inoculation can be proposed as an effective agronomic practice in wheat production and as a sustainable cultural practice to manage soil biofunctioning. To fully promote inoculation practices, a better knowledge of AMF ecology has to be acquired to better adapt AMF inoculation to environmental conditions, and thus warrant better yields and agricultural sustainability. 展开更多
关键词 ARBUSCULAR MYCORRHIZAL Fungi Field-Grown WHEAT MYCORRHIZAL FIELD Inoculation Nutrient Uptake Microbial Soil Functions
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Ore Texture,Mineralogy and Whole Rock Geochemistry of the Iron Mineralization from Edea North Area,Nyong Complex,Southern Cameroon:Implication for Origin and Enrichment Process 被引量:1
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作者 Bravo Martin Mbang Bonda Jacques Etame +4 位作者 Arnaud Patrice Kouske Elie Constantin Bayiga Gilbert Francois Ngon Ngon Simon Joel Mbai Martine Gerard 《International Journal of Geosciences》 2017年第5期659-677,共19页
This study presents the ore texture, mineralogy and whole rock geochemistry of iron occurrence from the Edea North area located at the upper limit of the Nyong Unit, part of the Congo craton. This iron mineralization ... This study presents the ore texture, mineralogy and whole rock geochemistry of iron occurrence from the Edea North area located at the upper limit of the Nyong Unit, part of the Congo craton. This iron mineralization is of magnetite quartzite type enclosed by metamorphic rocks of the granulite facies. Two main facies have been identified over the study area including the banded and the massive facies. The mineralogical set of these facies is in majority represented by magnetite, quartz and pyroxene martite in addition to minor biotite, apatite, and amphibole. Magnetite presents as irregular and elongated minerals which can contain quartz inclusions of various shapes and sizes, as blasts clustering, around pyroxenes and isolated xenomorphic magnetite minerals in the silicate phases. Quartz varies from fine to coarse-grained and ribbon quartz. This indicates re-crystallization and deformation during metamorphism. Electron microprobe analysis on magnetite and martite show Fe2O3 contents that vary between 96.11 and 99.76. Whole rock chemical data showed that Fe-contents are as high as 62.9 wt%. The SiO2 content varies between 33.8 wt% and 51.2 wt%. Iron oxides and SiO2 are negatively correlated. Moreover, the low positive correlations between Al2O3 and HFSE, and LILE suggest a contribution of clastic materials in the protolith of studied materials. The samples show low contents of V, Cr, Ba, Zr with respect to igneous rocks. This may infer a sedimentary origin for the studied rocks;furthermore, these materials may have undergone hydrothermal alteration. The REE patterns reveal enrichment in LREE compared to HREE. Some samples show positive Eu (1.82) and other negative anomalies Eu (0.54 to 0.97). The lack of Ce anomalies suggests that the depositional environment of the Edea North iron occurrence was anoxic or suboxic. Overall, the Edea North iron occurrence may have undergone significant input from hydrothermal sources with imprints of the clastic during its deposition. 展开更多
关键词 MAGNETITE Texture Edea North Nyong Complex Southern Cameroon
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Effect of 24-Epibrassinolide on Growth of <i>in Vitro</i>Shoot Tips of Different Yam (<i>Dioscorea</i>Spp.) Species
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作者 Isabelle Engelmann-Sylvestre Florent Engelmann 《American Journal of Plant Sciences》 2013年第11期2271-2274,共4页
In this work we compared the effect of the growth regulator content of the culture medium on the growth of in vitro shoot tips of five yam accessions belonging to four yam species (one Dioscorea alata, one D. rotundat... In this work we compared the effect of the growth regulator content of the culture medium on the growth of in vitro shoot tips of five yam accessions belonging to four yam species (one Dioscorea alata, one D. rotundata, one D. cayenensis and two D. trifida). Medium S contained 0.6 μM benzyl adenine, 1.07 μM naphthalene acetic acid and 0.23 μM gibberellic acid while medium EBR contained 0.23 μM gibberellic acid and 0.1 μM 24-epibrassinolide. After 2 months of culture, oxidation level was significantly reduced on medium EBR compared to medium S for four of the five accessions tested. By contrast, medium EBR did not have any positive effect on shoot length since length of shoots produced after 2 months of culture on medium S and EBR were similar, except with accession 3-45T, for which shoot length was shorter on medium S compared to medium EBR. These results underline the potential of 24-epibrassinolide to reduce oxidation phenomena during in vitro culture and call for its utilization for regeneration of cryopreserved yam shoot tips, which is often impeded by oxidation phenomena. 展开更多
关键词 YAM DIOSCOREA Spp. 24-EPIBRASSINOLIDE Oxidation Shoot Tip In Vitro Culture Cryopreservation
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Nematodes for Soil Quality Monitoring: Results from the RMQS BioDiv Programme
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作者 Cécile Villenave Anne Jimenez +6 位作者 Muriel Guernion Guénola Pérès Daniel Cluzea Thierry Mateille Bernard Martiny Mireille Fargette Johannes Tavoillot 《Open Journal of Soil Science》 2013年第1期30-45,共16页
A French programme, “Réseau de mesure de la qualité des sols: biodiversité des organismes” (RMQS BioDiv) was developed in Brittany (27,000 km2 in the western part of France) as an initial assessment o... A French programme, “Réseau de mesure de la qualité des sols: biodiversité des organismes” (RMQS BioDiv) was developed in Brittany (27,000 km2 in the western part of France) as an initial assessment of soil biodiversity on a regional scale in relation to land use and pedoclimatic parameters. The nematode community assemblages were compared among the land use categories. Crops were characterised by a high abundance of bacterial-feeders, particularly opportunistic bacterial-feeders belonging to Rhabditidae. Meadows presented a higher total abundance of nematodes than did crops (20.6 ind·g-1 dry soil vs. 13.1 ind·g-1 dry soil), and they were mainly linked to the great abundance of plant-parasitic nematodes, particularly Meloidogyne, but with a very high heterogeneity between sampled plots. The nematodes were most abundant in forests (23.7 ind·g-1 dry soil) and presented the most structured community (SI = 82.2 in forests vs. 58.6 and 55.5 in crops and meadows, respectively). Forests had also the higher fungal component (fungal-feeders and facultative plant-feeders belonging to the Tylenchidae) leading to a significant higher part of the fungal decomposition pathway in forests than in crops. The ability of different taxonomic levels of nematode identifica- tion to discriminate among different cropping systems (i.e., continuous cropping system, crop with meadow in the rota- tion, meadow with crop in the rotation and permanent meadow) was also tested. The family level (48 families identified in these samples) was more efficient than the other taxonomic levels (86 taxa, 17 functional guilds and 6 trophic groups): best statistical significant discrimination for time spent in identification. The relation between the nematode ecological indices, the abundance of nematode trophic groups and the crop management practices were studied. The effects of fertilization, ploughing frequency, use of pesticides and management systems on ecological indices, particu- larly on the Maturity Indices, were observed. 展开更多
关键词 Agricultural Practices BIOINDICATORS CROP Forest MEADOW Soil BIODIVERSITY MONITORING
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Influence of Different Environments on Germination Parameters and Seedling Morphology in <i>Khaya senegalensis</i>(Desr.) A. Juss (Meliaceae)
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作者 Beda Innocent Adji Sélastique Doffou Akaffou +3 位作者 Kouadio Henri Kouassi Yao Patrice Houphouet Jerôme Duminil Sylvie Sabatier 《American Journal of Plant Sciences》 2020年第10期1579-1600,共22页
<i>Khaya senegalensis</i><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> is one of the largest and most majestic ... <i>Khaya senegalensis</i><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> is one of the largest and most majestic trees in Africa. Overexploited for its precious wood and medicinal values, the natural stands of this species are in danger of extinction in Cote d’Ivoire. Its sustainable management through regeneration techniques and assessment of its degree of adaptation to the changing climate is necessary. </span><span style="font-family:Verdana;">The aim of this study is</span><span style="font-family:Verdana;"> to evaluate the effect of different environments on seedling germination and development in </span><span style="font-family:Verdana;"><i>Khaya senegalensis</i></span><span style="font-family:Verdana;">. A total of 2160 seeds from different mother plants and 540 individuals from seed germination were selected and evaluated. The trials were conducted on three sites that were distinct by their microclimate (two nurseries in Cote d’Ivoire and one greenhouse in France). Analysis of variance showed that germination and morphology parameters were not influenced by the characteristics of the mother plants used (p > 0.05), but rather by the study sites (P < 0.05). The stable and controlled greenhouse climate was more advantageous for latency time (12.66 ± 0.80 days), germination delay (16.96 96 ± 0.54 days), germination speed (19.66 ± 2.95 days), germination duration (10.83 ± 2.27 days) and germination rate (88.88 ± 7.97) with more vigorous sowing than the other two sites. The results showed in general that the higher the height of the seedlings, the thicker the diameter of the seedlings (r = 0.796) and the higher the number of leaves (r = 0.946). This savannah species is native to the arid zones of Africa, but this study highlighted its adaptive potential to changing and different climates. These results are decision support tools for the regeneration of native pioneer forest species with high agroforestry potential and socio-economic importance such as </span><span style="font-family:Verdana;"><i>Khaya senegalensis</i></span><span style="font-family:Verdana;">. This study could be extended to other species </span><span style="font-family:Verdana;">in order to</span><span style="font-family:Verdana;"> restore disturbed ecosystems.</span></span></span></span> 展开更多
关键词 Khaya senegalensis Environments Germination Parameters GREENHOUSE Côte d’Ivoire
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Exposure of Common Bean Seeds to Liquid Nitrogen Modifies Mineral Composition of Young Plantlet Leaves
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作者 Inaudis Cejas Annekathrin Rumlow +5 位作者 Ariel Turcios Florent Engelmann Marcos Edel Martínez Lourdes Yabor Jutta Papenbrock José Carlos Lorenzo 《American Journal of Plant Sciences》 2016年第12期1612-1617,共6页
Many publications describe cryopreservation techniques but only a few studies have focused on the biochemical and physiological changes occurring in plants regenerated from seeds exposed to liquid nitrogen. This paper... Many publications describe cryopreservation techniques but only a few studies have focused on the biochemical and physiological changes occurring in plants regenerated from seeds exposed to liquid nitrogen. This paper aims at describing the effect of common bean seed cryostorage on mineral nutrition of young plantlets. The following elements were measured on leaves of 10-day-old plantlets from non-cryopreserved and cryopreserved seeds: Al, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, S, Se, Sr and Zn. At 10 days after sowing, both treatments (control and cryopreserved seeds) showed 100% seed germination without any visual phenotypic difference. However, contents of several elements in the leaves were different. Exposure of seeds to liquid nitrogen decreased Cu, Cd and Na uptake and increased absorption of B and Al. Further studies are required to understand the mechanisms underlying the relationship between seed exposure to liquid nitrogen and mineral nutrition during the early stages of plantlet growth. 展开更多
关键词 Common Bean CRYOPRESERVATION CRYOSTORAGE
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A diagnostic protocol designed for determining allergic causes in patients with blood eosinophilia
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作者 Jean-François Magnaval Guy Laurent +2 位作者 Noemie Gaudré Judith Fillaux Antoine Berry 《Military Medical Research》 SCIE CAS 2017年第4期181-192,共12页
Background: Blood eosinophilia is a common laboratory abnormality, and its characterization frequently represents a quandary for primary care physicians. Consequently, in France, specialists and particularly hematolog... Background: Blood eosinophilia is a common laboratory abnormality, and its characterization frequently represents a quandary for primary care physicians. Consequently, in France, specialists and particularly hematologists, often must investigate patients who present with blood eosinophilia that often, but not always, occurs because of allergic causes. Both the Departments of Hematology and Parasitology at Toulouse University Hospitals established a collaboration to rule out allergic causes of eosinophilia, particularly helminthiases, prior to initiating more sophisticated investigations.Methods: Since 2004, the authors employed the same protocol to investigate eosinophilic outpatients who attended the clinic of Parasitology at Toulouse University Hospitals, and they reported the performance of this diagnostic procedure that was designed to be rapid(no hospitalization required) and only moderately expensive.Results: A total of 406 patients who presented with blood eosinophilia greater than 0.5(×10~9, giga cells per litter, G/L) had an allergic etiology in 350(86.2%) cases. Among the remaining 56 subjects, 17 did not undergo a follow-up and 39 were referred to another specialized department, mostly Hematology. However, only 21 patients attended then were subsequently investigated. Non-allergic causes of eosinophilia, including 3 cases of the lymphoid variant of hypereosinophilic syndrome and 2 cases of myeloproliferative disorder, were identified in 14 patients, whereas 7 remained diagnosed as having idiopathic eosinophilia.Conclusion: This study underlines the need to investigate patients presenting with even moderate blood eosinophilia. The work-up that was employed appears to be efficient and versatile and may be used by any medical specialist, such as in hematology, infectious disease, or internal medicine departments, who needs to investigate eosinophilic patients and should initially rule out any etiology of allergic eosinophilia. 展开更多
关键词 Blood eosinophilia Diagnostic protocol Classification Secondary eosinophilias ALLERGY Helminthiases
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Protein Quality of Amaranth Grains Cultivated in Ethiopia as Affected by Popping and Fermentation
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作者 Endale Amare Claire Mouquet-Rivier +3 位作者 Adrien Servent Gilles Morel Abdulaziz Adish Gulelat Desse Haki 《Food and Nutrition Sciences》 2015年第1期38-48,共11页
The effect of popping and fermentation on protein quality of three different varieties of amaranth grains cultivated in Ethiopia was evaluated. Total lysine content of the grains was higher than that of commonly avail... The effect of popping and fermentation on protein quality of three different varieties of amaranth grains cultivated in Ethiopia was evaluated. Total lysine content of the grains was higher than that of commonly available cereals but close to that of legumes. Methionine and cysteine contents in the grains were also higher than that found in cereal and legume proteins. Percentage of total indispensable amino acids, excluding tryptophan, was 43% - 49%, which was higher than WHO reference pattern (31%). Popping resulted in 36% and 37% reduction in total lysine and cysteine contents, respectively, whereas fermentation reduced cysteine, lysine and methionine contents by 16%, 20% and 20%, respectively. From the free amino acids, histidine was the major indispensable amino acid but threonine was not detected. During popping, all free amino acids, except threonine, were reduced. On the other hand, fermentation significantly increased (p < 0.01) most amino acids except arginine, which was significantly decreased (p < 0.01), and tyrosine and glutamic acid, for which no change was observed. Popping decreased in vitro protein digestibility (IVPD) by 8.3% - 17.1% while fermentation increased IVPD by 4.8% - 7.5%. Substitution of amaranth for wheat and/or maize during complementary food formulation could contribute much to the daily requirements of indispensable amino acids of young children. 展开更多
关键词 AMARANTH Grain Indispensable AMINO ACIDS Popping FERMENTATION Protein DIGESTIBILITY Complementary Food
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Effect of the seeds provenance and treatment on the germination rate and plants growth of four forest trees species of Cote d’Ivoire
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作者 Sélastique Doff ou Akaff ou AiméKouassi Kouame +5 位作者 Nestor Bi Boh Gore Georges Yao Abessika Henri Kouadio Kouassi Perla Hamon Sylvie Sabatier Jerome Duminil 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第1期161-169,共9页
The rapid rate of deforestation in Cote d’Ivoire has led to loss of plant species diversity and also threatens some commercial tree species with extinction.Some reforestation and aff orestation has been completed.How... The rapid rate of deforestation in Cote d’Ivoire has led to loss of plant species diversity and also threatens some commercial tree species with extinction.Some reforestation and aff orestation has been completed.However,for some species,the numbers of surviving transplants has declined.Hence,it is necessary to develop properly adapted and resilient genotypes that can eff ectively support the programs of forest restoration.In this context we evaluated the eff ects of the provenances of seeds and of various treatments on the germination rates and on plant growth of four commercial trees species(Pycnanthus angolensis,Terminalia superba,Mansonia altissima and Pterygota macrocarpa).We analyzed these parameters for seeds of three provenances(Daloa,Akoupéand Daoukro)of four species and for thirty plants aged 6 months per provenance.Time to begin germination and time to reach maximum germination were similar among species,and were not infl uenced by either treatment or provenance.Untreated seeds and those soaked for 24 and 48 h in water at room temperature yielded the highest germination rates,irrespective of species or provenance.The one exception was P.angolensis,for which no germination was recorded.Within species,some provenances produced higher germination percentages than did others.No clear relationship was computed between the germination rate and the morphometric characteristics of the seeds which varied signifi cantly between provenances.Plant growth and morphological variability also depended greatly on provenance.Genetic factors might be implicated,therefore provenance trials should be undertaken and evaluated.Furthermore,molecular analysis should be undertaken to confi rm the implications of genetic factors and allow for genetic selection. 展开更多
关键词 Forest trees Seed germination Plant growth PROVENANCE Cote d’Ivoire
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