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Root overlap and allocation of above- and belowground growth of European beech in pure and mixed stands of Douglas fir and Norway spruce
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作者 Amani S.Lwila Christian Ammer +2 位作者 Oliver Gailing Ludger Leinemann Martina Mun 《Forest Ecosystems》 SCIE CSCD 2024年第5期591-602,共12页
Site conditions and species identity have a combined effect on fine root growth of trees in pure and mixed stands.However,mechanisms that may contribute to this effect are rarely studied,even though they are essential... Site conditions and species identity have a combined effect on fine root growth of trees in pure and mixed stands.However,mechanisms that may contribute to this effect are rarely studied,even though they are essential to assess the potential of species to cope with climate change.This study examined fine root overlap and the linkage between fine root and stem growth of European beech(Fagus sylvatica)growing in pure and mixed stands with Douglas fir(Pseudotsuga menziesii)or Norway spruce(Picea abies)at two different study sites in northwestern Germany.The study sites represented substantially different soil and climate conditions.At each site,three stands,and at each stand,three pairs of trees were studied.In the pure beech stand,the pairs consisted of two beech trees,while in the mixed stands each pair was composed of a beech tree and a conifer.Between each pair,three evenly spaced soil cores were taken monthly throughout the growing season.In the pure beech stands,microsatellite markers were used to assign the fine roots to individual trees.Changes in stem diameter of beech were quantified and then upscaled to aboveground wood productivity with automatic high-resolution circumference dendrometers.We found that fine root overlap between neighboring trees varied independently of the distance between the paired trees or the stand types(pure versus mixed stands),indicating that there was no territorial competition.Aboveground wood productivity(wood NPP)and fine root productivity(root NPP)showed similar unimodal seasonal patterns,peaking in June.However,this pattern was more distinct for root NPP,and root NPP started earlier and lasted longer than wood NPP.The influence of site conditions on the variation in wood and root NPP of beech was stronger than that of stand type.Wood NPP was,as expected,higher at the richer site than at the poorer site.In contrast,root NPP was higher at the poorer than at the richer site.We concluded that beech can respond to limited resources not only above-but also belowground and that the negative relationship between above-and belowground growth across the study sites suggests an‘optimal partitioning’of growth under stress. 展开更多
关键词 Fine root growth Stem growth Trade-off Cost-benefit ratio Belowground territoriality Conspecific neighbors Heterospecific neighbors
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Overexpression of the peroxidase gene ZmPRX1 increases maize seedling drought tolerance by promoting root development and lignification
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作者 Xiuzhen Zhai Xiaocui Yan +6 位作者 Tinashe Zenda Nan Wang Anyi Dong Qian Yang Yuan Zhong Yue Xing Huijun Duan 《The Crop Journal》 SCIE CSCD 2024年第3期753-765,共13页
Drought is a main abiotic stress factor hindering plant growth,development,and crop productivity.Therefore,it is crucial to understand the mechanisms by which plants cope with drought stress.Here,the function of the m... Drought is a main abiotic stress factor hindering plant growth,development,and crop productivity.Therefore,it is crucial to understand the mechanisms by which plants cope with drought stress.Here,the function of the maize peroxidase gene ZmPRX1 in drought stress tolerance was investigated by measurement of its expression in response to drought treatment both in a ZmPRX1 overexpression line and a mutant line.The higher root lignin accumulation and seedling survival rate of the overexpression line than that of the wild type or mutant support a role for ZmPRX1 in maize drought tolerance by regulating root development and lignification.Additionally,yeast one-hybrid,Dule luciferase and ChIP-qPCR assays showed that ZmPRX1 is negatively regulated by a nuclear-localized ZmWRKY86 transcription factor.The gene could potentially be used for breeding of drought-tolerant cultivars. 展开更多
关键词 Drought tolerance MAIZE ZmPRX1 root development Lignin biosynthesis
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Coupling and coordination relationship of tourism inclusive green growth system:Evidence from Shandong Province
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作者 Tianjun Xu Gangmin Weng Wei Guo 《Chinese Journal of Population,Resources and Environment》 2024年第3期334-342,共9页
Sustainable growth is a prerequisite for high-quality development,and inclusive green growth is regarded as an important way to realize sustainable growth.This paper constructs a tourism inclusive green growth index(I... Sustainable growth is a prerequisite for high-quality development,and inclusive green growth is regarded as an important way to realize sustainable growth.This paper constructs a tourism inclusive green growth index(IGGI)system based on the 2018 Asian Development Bank IGGI.Using Shandong Province from 2017 to 2019,the entropy weight method is utilized to explore the degree of coupling and coordination among the subsystems of tourism inclusive green growth.The study shows that:(1)the tourism IGGI continues to grow;(2)in the tourism inclusive green growth system,the social equity subsystem shows a trend of steady improvement;and(3)in the system,there is a slight discordance between the economic growth subsystem and the environmental sustainability subsystem.The study aims to provide the scientific basis for the high-quality development of tourism and theoretical support for the field of tourism and environmental sustainability. 展开更多
关键词 Tourism inclusive green growth system Coupled coordination Entropy law Tourism quality development
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Effects of Water-retaining Agents on Growth, Development, Yield and Quality of Soybean under Drought Stress
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作者 Hui XIA Yan ZHANG +2 位作者 Yun HAN Shasha HU Hengbin ZHANG 《Plant Diseases and Pests》 2024年第3期34-39,共6页
[Objectives]The paper was to explore the effects of different doses of water-retaining agent on the growth and development indicators,yield and quality of soybean plants subjected to drought stress.[Methods]The effect... [Objectives]The paper was to explore the effects of different doses of water-retaining agent on the growth and development indicators,yield and quality of soybean plants subjected to drought stress.[Methods]The effects of drought stress(MDS)and drought stress with low(MDS-L),medium(MDS-M)and high doses(MDS-H)of the water-retaining agent on the growth and development indicators,root activity,MDA content,antioxidant enzyme activity,yield and quality of soybean were studied by field plot test,with the normal water supply serving as the control(CK).[Results]In response to drought stress,the plant height,stem diameter,and yield of soybean exhibited a notable decline.Additionally,the contents of protein,fat,linoleic acid,and linolenic acid in seeds demonstrated a significant reduction.Conversely,the root activity and antioxidant enzyme activity exhibited a noticeable decline,while the MDA content exhibited an increase.The application of varying doses of the water-retaining agent was found to significantly enhance soybean growth,stimulate root activity,and elevate antioxidant enzyme activity,while concurrently reducing MDA content.The observed effects were found to be dose-dependent,with the greatest effects observed at the highest dose.In comparison to MDS,the yields of soybean in the MDS-L,MDS-M,and MDS-H treatments exhibited a 18.38%,25.58%,and 46.26%increase,respectively.Additionally,the content of protein,fat,linoleic acid,and linolenic acid in seeds demonstrated a notable enhancement.[Conclusions]The application of the water-retaining agent has been demonstrated to significantly promote the growth of soybean plants under conditions of drought stress,resulting in an improvement in both the yield and the quality of the soybean crop.The recommended dosage of the water-retaining agent is 3.3 kg/667 m 2. 展开更多
关键词 SOYBEAN Water-retaining agent YIELD Quality growth and development Antioxidant enzyme activity
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Delineation of urban growth boundary based on FLUS model under the perspective of land use evaluation in hilly mountainous areas 被引量:1
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作者 ZHANG Yunping LIN Jianping +3 位作者 HUANG Yimin CHEN Zebin ZHU Chenhui YUAN Hao 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1647-1662,共16页
With rapid economic development,the size of urban land in China is expanding dramatically.The Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control ... With rapid economic development,the size of urban land in China is expanding dramatically.The Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control the urban sprawl.Reasonable delineation of UGB can inhibit the disorderly spread of urban space and guide the normal development of the city.It is of practical significance for the construction of green urban space.The study utilizes GIS technology to establish a land construction suitability evaluation system for Nankang city,which is experiencing rapid urban expansion,and outlines the preliminary UGB under the future land use simulation(FLUS)model.At the same time,considering the coupled coordination of"Production-Living-Ecological Space",and based on the suitability evaluation,we revised the preliminary UGB by combining the advantages of the patch-generating land use simulation(PLUS)model and the convex hull model to delineate the final UGB.The results show that:1)the comprehensive score of the evaluation of the suitability of the construction of land from high to low shows the distribution of the center of the city to the surrounding circle type spread,the center of the city has the highest suitability score.The results of convex hull model show that the urban expansion type of Nankang is epitaxial.In the future,the urban expansion will mainly occur in the northern part of the city.The PLUS model predicts an increase of 3359.97 hm^(2)of construction land in Nankang by 2035,of which 2022.97 hm^(2)is urban construction land.2)The FLUS model has a prediction accuracy of 86.3%and delineates a preliminary UGB area of 9215.07 hm^(2).3)We used the results of the construction suitability evaluation,PLUS model simulation results,and convex hull model predictions to revise the originally delineated UGB.The final delineated UGB area is 8895.67 hm^(2)and it is capable of meeting the future development of the study area.The results of the delineation can promote sustainable urban development,and the delineation methodology can provide a reference basis for the preparation of territorial spatial planning. 展开更多
关键词 Urban sprawl FLUS model Spatial correction Urban growth boundary Sustainable development
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Transcriptomic and epigenomic landscapes of muscle growth during the postnatal period of broilers
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作者 Shuang Gu Qiang Huang +3 位作者 Yuchen Jie Congjiao Sun Chaoliang Wen Ning Yang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期1851-1865,共15页
Background Broilers stand out as one of the fastest-growing livestock globally,making a substantial contribution to animal meat production.However,the molecular and epigenetic mechanisms underlying the rapid growth an... Background Broilers stand out as one of the fastest-growing livestock globally,making a substantial contribution to animal meat production.However,the molecular and epigenetic mechanisms underlying the rapid growth and development of broiler chickens are still unclear.This study aims to explore muscle development patterns and regulatory networks during the postnatal rapid growth phase of fast-growing broilers.We measured the growth performance of Cornish(CC)and White Plymouth Rock(RR)over a 42-d period.Pectoral muscle samples from both CC and RR were randomly collected at day 21 after hatching(D21)and D42 for RNA-seq and ATAC-seq library construction.Results The consistent increase in body weight and pectoral muscle weight across both breeds was observed as they matured,with CC outpacing RR in terms of weight at each stage of development.Differential expression analysis identified 398 and 1,129 genes in the two dimensions of breeds and ages,respectively.A total of 75,149 ATAC-seq peaks were annotated in promoter,exon,intron and intergenic regions,with a higher number of peaks in the promoter and intronic regions.The age-biased genes and breed-biased genes of RNA-seq were combined with the ATAC-seq data for subsequent analysis.The results spotlighted the upregulation of ACTC1 and FDPS at D21,which were primarily associated with muscle structure development by gene cluster enrichment.Additionally,a noteworthy upregulation of MUSTN1,FOS and TGFB3 was spotted in broiler chickens at D42,which were involved in cell differentiation and muscle regeneration after injury,suggesting a regulatory role of muscle growth and repair.Conclusions This work provided a regulatory network of postnatal broiler chickens and revealed ACTC1 and MUSTN1 as the key responsible for muscle development and regeneration.Our findings highlight that rapid growth in broiler chickens triggers ongoing muscle damage and subsequent regeneration.These findings provide a foundation for future research to investigate the functional aspects of muscle development. 展开更多
关键词 ATAC-seq BROILER Pectoral muscle development Rapid growth RNA-SEQ
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Career Development of Higher Education Teachers:Opportunities,Challenges,and Strategies for Success
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作者 ZHANG Mengdi WANG Zhen 《Cultural and Religious Studies》 2024年第9期587-590,共4页
Career development for higher education teachers plays a crucial role in enhancing both the quality of education and the professional satisfaction of academic staff.This essay explores the various stages of career dev... Career development for higher education teachers plays a crucial role in enhancing both the quality of education and the professional satisfaction of academic staff.This essay explores the various stages of career development for educators,including entry into academia,professional growth,and leadership advancement.It examines the challenges these educators face-such as the balance between teaching,research,and service-and presents strategies that institutions and individuals can adopt to foster career growth.Key factors like mentorship,continuing education,and institutional support are discussed as critical to enabling sustainable career progression.The essay concludes by underscoring the importance of ongoing development to ensure teachers can meet evolving educational demands. 展开更多
关键词 career development higher education professional growth academic staff MENTORSHIP
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The Function of GABA in Plant Cell Growth, Development and Stress Response 被引量:1
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作者 Yue Jin Lulu Zhi +3 位作者 Xin Tang Yilin Chen John T.Hancock Xiangyang Hu 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第8期2211-2225,共15页
Gamma-aminobutyric acid(GABA)is a ubiquitous four-carbon non-protein amino acid that is involved in various physiological processes of plant growth and development,such as root architecture,stem elongation,leaf senesc... Gamma-aminobutyric acid(GABA)is a ubiquitous four-carbon non-protein amino acid that is involved in various physiological processes of plant growth and development,such as root architecture,stem elongation,leaf senescence,pollen tube growth,fruit ripening,and seed germination.GABA is also related to plant stress responses,such as drought,salt,cold,and heat stresses.Regulation of GABA in plant stress responses is complex and involves multiple signaling pathways,including calcium and hormone signaling.This paper systematically reviews the synthesis,metabolic pathways and regulatory role of GABA in plants,which will provide new insights into the understanding of plant growth and stress responses and offer novel strategies for improving crop productivity and stress. 展开更多
关键词 GABA STRESS growth and development
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Effects of stress-induced ABA on root architecture development:Positive and negative actions
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作者 Zhenning Teng Jiahan Lyu +2 位作者 Yinke Chen Jianhua Zhang Nenghui Ye 《The Crop Journal》 SCIE CSCD 2023年第4期1072-1079,共8页
Root architecture development,an agronomic trait that influences crop yield,is regulated by multiple plant hormones.Abscisic acid(ABA)is a stress hormone that responds to multiple stresses,including salt,drought,and c... Root architecture development,an agronomic trait that influences crop yield,is regulated by multiple plant hormones.Abscisic acid(ABA)is a stress hormone that responds to multiple stresses,including salt,drought,and cold stress,and modulates various aspects of plant growth and development.In recent years,it has been found that ABA synthesized under mild stress or well-watered conditions can support plant growth and stress resistance by positively regulating root architecture development.In this review,we summarize the molecular,cellular,and organismal basis of ABA homeostasis in the root and how ABA signaling affects root architecture development both as an inhibitor and as an activator.We discuss the implications of these studies and the potential for exploiting the components of ABA signaling in designing crop plants with improved root system development and stress resistance. 展开更多
关键词 Abscisic acid rootS growth and development HOMEOSTASIS
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Abnormal Secondary Growth and Histochemical Localization of Alkaloids in Root System of Aconitum flavum Hand.-Mazz.
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作者 祁建钊 郭继元 徐青 《Agricultural Science & Technology》 CAS 2011年第9期1313-1317,共5页
[Objective] The purpose of this study was to clarify the structure,growth pattern and histochemical localization of alkaloids in root system of Aconitum flavum Hand.-Mazz.[Method] Paraffin sectioning and histochemistr... [Objective] The purpose of this study was to clarify the structure,growth pattern and histochemical localization of alkaloids in root system of Aconitum flavum Hand.-Mazz.[Method] Paraffin sectioning and histochemistry were employed for performing the analysis in this study.[Result] The root system of Aconitum flavum Hand.-Mazz.consists of taproot,lateral root and adventitious root.The primary structure of root system is normal,but secondary structure shows abnormal.The cambium and the extra cambium of taproot form a "U"-shaped secondary vascular bundle and tertiary bundle in abnormal secondary structure.The sieve tube group is made of little sieve tube group which is differentiated from primary phloem and cambium.Meanwhile,the secondary xylem in tuberous root also appears to be a "U" shape.Parenchyma cells of secondary phloem occupy most of the tuberous root.The sieve tube group of tuberous root is mainly differentiated from parenchyma cell of secondary phloem.[Conclusion] The difference in abnormal secondary structure of taproot and tuberous root are attributed to their varied cambium compose and activity pattern.Alkaloids are mainly accumulated in parenchyma cell of the inside cortex and between bundle in taproot,while parenchyma of secondary phloem and pith in tuberous root. 展开更多
关键词 Aconitum flavum Hand. - Mazz. root system Abnormal secondary growth ALKALOIDS Histochemical localization
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Effects of Root Growth of Deep and Shallow Rooting Rice Cultivars in Compacted Paddy Soils on Subsequent Rice Growth
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作者 Md.Dhin ISLAM Adam H.PRICE Paul D.HALLETT 《Rice science》 SCIE CSCD 2023年第5期459-472,I0022-I0024,共17页
Rice is often grown as multiple seasons in one year,alternating between flooded and upland systems.A major constraint,introduced from the flooded system,is a plough pan that may decrease rooting depth and productivity... Rice is often grown as multiple seasons in one year,alternating between flooded and upland systems.A major constraint,introduced from the flooded system,is a plough pan that may decrease rooting depth and productivity of follow-on upland rice.Roots penetrating the plough pan under flooded rice system can leave a legacy of weaker root growth pathways.Deeper rooting rice cultivars could have a bigger impact,but no direct evidence is available.To explore whether a deep rather than a shallow rooting rice cultivar grown in a flooded cropping cycle benefited deeper root growth of follow-on rice in an upland,reduced tillage cropping cycle,a simulated flooded paddy in greenhouse was planted with deep(Black Gora) and shallow(IR64) rooting cultivars and a plant-free control.Artificial plough pans were made in between the topsoil and subsoil to form different treatments with no plough pan(0.35 MPa),soft plough pan(1.03 MPa) and hard plough pan(1.70 MPa).After harvest of this ‘first season’ rice,the soil was drained and undisturbed to simulate zero-tillage upland and planted rice cultivar BRRI Dhan 28.The overall root length density(RLD),root surface area,the numbers of root tips and branching of BRRI Dhan 28 did not vary between plough pan and no plough pan treatments.Compared with the shallow rooting rice genotype,the deep rooting rice genotype as ‘first season’ crop produced 19% greater RLD,34% greater surface area and 29% more branching of BRRI Dhan 28 in the subsoil.In the topsoil,however,BRRI Dhan 28 had 28% greater RLD,35% greater surface area and 43% more branching for the shallow rather than deep rooting genotype planted in the ‘first season’.The results suggested that rice cultivar selection for a paddy cycle affects root growth of a follow-on rice crop grown under no-till,with benefits to subsoil access from deep rooting cultivars and topsoil proliferation for shallow rooting cultivars. 展开更多
关键词 plough pan root growth biopores crop rotation Oryza sativa preceding crop ZERO-TILLAGE
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Effects of Allelochemicals on Root Growth and Pod Yield in Response to Continuous Cropping Obstacle of Peanut
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作者 Zhaohui Tang Feng Guo +8 位作者 Li Cui Qingkai Li Jialei Zhang Jianguo Wang Sha Yang Jingjing Meng Xinguo Li Ping Liu Shubo Wan 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第1期17-34,共18页
Continuous cropping(CC)obstacle is a major threat in legume crops production;however,the underlying mechanisms concerning the roles allelochemicals play in CC obstacle are poorly understood.The current 2-year study wa... Continuous cropping(CC)obstacle is a major threat in legume crops production;however,the underlying mechanisms concerning the roles allelochemicals play in CC obstacle are poorly understood.The current 2-year study was conducted to investigate the effects of different kinds and concentrations of allelochemicals,p-hydroxybenzoic acid(H),cinnamic acid(C),phthalic acid(P),and their mixtures(M)on peanut root growth and productivity in response to CC obstacle.Treatment with H,C,P,and M significantly decreased the plant height,dry weight of the leaves and stems,number of branches,and length of the lateral stem compared with control.Exogenous application of H,C,P,and M inhibited the peanut root growth as indicated by the decreased root morphological characters.The allelochemicals also induced the cell membrane oxidation even though the antioxidant enzymes activities were significantly increased in peanut roots.Meanwhile,treatment with H,C,P,and M reduced the contents of total soluble sugar and total soluble protein.Analysis of ATPase activity,nitrate reductase activity,and root system activity revealed that the inhibition effects of allelochemicals on peanut roots might be due to the decrease in activities of ATPase and NR,and the inhibition of root system.Consequently,allelochemicals significantly decreased the pod yield of peanut compared with control.Our results demonstrate that allelochemicals play a dominant role in CC obstacle-induced peanut growth inhibition and yield reduction through damaging the root antioxidant system,unbalancing the osmolytes accumulation,and decreasing the activities of root-related enzymes. 展开更多
关键词 PEANUT continuous cropping obstacle root growth pod yield
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Effects of Antimony Stress on Root Growth,Antimony Accumulation and Physiological Characteristics of Ramie(Boehmeria nivea(L.) Gaudich.)
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作者 Jiecheng HAN Yaxuan LIU +4 位作者 Xingguo ZHAN Jingyao LUO Fulong YANG Jing ZHOU Guiyuan MENG 《Agricultural Biotechnology》 CAS 2023年第1期8-11,15,共5页
[Objectives]This study was conducted to investigate the toxicity of heavy metal antimony(Sb) to ramie(Boehmeria nivea(L.) Gaudich.) and the tolerance response in ramie. [Methods] A pot experiment was conducted to stud... [Objectives]This study was conducted to investigate the toxicity of heavy metal antimony(Sb) to ramie(Boehmeria nivea(L.) Gaudich.) and the tolerance response in ramie. [Methods] A pot experiment was conducted to study the effects of Sb stress on root growth and Sb accumulation and transport of the root system of cultivated ramie Zhongzhu No.1, as well as on the physiological characteristics of ramie leaves. [Results] The plant height and root dry weight and volume of Zhongzhu No.1 showed an effect of "promoting at low concentrations and inhibiting at high concentrations" with the increase of Sb concentration, and decreased significantly at the concentration of 4 000 mg/kg, but no obvious toxic growth symptoms were observed. The content of Sb in roots(289.7-508.6 mg/kg) and the root-shoot transfer factor(0.09-0.57) of Zhongzhu No.1 increased with the increase of soil Sb concentration, but the change of Sb bioconcentration factor in roots was opposite, indicating that high concentrations of Sb in soil could promote the absorption of Sb in roots and the transport of Sb to the aboveground part, but the Sb enrichment capacity of roots was relatively reduced with the increase of soil Sb. Sb stress had a certain impact on the physiological characteristics of ramie leaves. With the increase of Sb treatment concentration, MDA, POD and SOD showed a change trend of "first increasing and then decreasing", while CAT gradually increased, indicating that Sb stress caused changes in the physiological characteristics of ramie leaves, thereby affecting plant growth and development. [Conclusions] This study provides a theoretical basis for ecological restoration of ramie in mining areas. 展开更多
关键词 ANTIMONY RAMIE root growth Sb enrichment Physiological characteristics
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Assessing the Contribution of Ecotourism to Economic Growth and Rural Development Offered by Wildlife Resources to People Living in Communities around Matusadonha National Park
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作者 Jesse Zvikonyaukwa Kudakwashe Musengi Clarice P Mudzengi 《Journal of Sustainable Business and Economics》 2023年第2期12-24,共13页
Ecotourism is one of the major drivers of economic growth and rural development in many countries involved in wildlife resource management.The objective was to assess the contribution of ecotourism to economic growth ... Ecotourism is one of the major drivers of economic growth and rural development in many countries involved in wildlife resource management.The objective was to assess the contribution of ecotourism to economic growth and rural development offered to people living in communities around Matusadonha National Park.A total of 140 participants were interviewed and questionnaires were administered to the same number of people.Data were analysed using both qualitative and quantitative methods.Results show that the majority of participants(57%)were females.Safari operations were the major(54.7%)ecotourism activity in Matusadonha National Park.Above half(58.8%)of participants indicated that ecotourism contributed toward economic growth in communities around Matusadonha National Park.Most people(343)were employed on a part-time basis from 2000 to 2022.Participants indicated that the standard of living in most communities increased by more than 50%.Above 50%of participants were satisfied with the contribution of ecotourism towards rural development.It can be concluded that ecotourism has the potential to improve economic growth and rural development if close monitoring and accountability of funds are monitored closely.Local people should be included in the accountability of funds and management of wildlife resources to improve economic benefits to local people. 展开更多
关键词 ECOTOURISM Wildlife resources Matusadonha National Park Economic growth Rural development
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Effects of different forms of yeast Saccharomyces cerevisiae on growth performance,intestinal development,and systemic immunity in early-weaned piglets 被引量:16
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作者 Zongyong Jiang Shaoyong Wei +8 位作者 Zhilin Wang Cui Zhu Shenglan Hu Chuntian Zheng Zhuang Chen Youjun Hu Li Wang Xianyong Ma Xuefen Yang 《Journal of Animal Science and Biotechnology》 CAS CSCD 2016年第1期78-85,共8页
The present study was conducted to determine effects of different forms of yeast (Saccharomyces cerevisiae, strain Y200007) on the growth performance, intestinal development, and systemic immunity in early-weaned pi... The present study was conducted to determine effects of different forms of yeast (Saccharomyces cerevisiae, strain Y200007) on the growth performance, intestinal development, and systemic immunity in early-weaned piglets. A total of 96 piglets (14-d old, initial average body weight of 4.5 kg) were assigned to 4 dietary treatments: (1) basa diet without yeast (Control); (2) basal diet supplemented with 3.00 g/kg live yeast (LY); (3) basal diet supplemented with 2.66 g/kg heat-killed whole yeast (HKY); and (4) basal diet supplemented with 3.00 g/kg superfine yeast powders (SFY). Diets and water were provided ad libitum to the piglets during 3-week experiment. Growth performance of piglets was measured weekly. Samples of blood and small intestine were collected at days 7 and 21 of experiment. Dietary supplementation with LY and SFY improved G:F of piglets at days ]-21 of the experiment (P 〈 0.05) compared to Control group. Serum concentrations of growth hormone (GH), triiodothyronine (T3), tetraiodothyronine (T4), and insulin growth factor 1 (iGF-1) in piglets at day 21 of the experiment were higher when fed diets supplemented with LY and SFY than those in Control group (P 〈 0.05). Compared to Control group, contents of serum urea nitrogen of piglets were reduced by the 3 yeast-supplemented diets (P 〈 0.05). Diets supplemented with LY increased villus height and villus-to-crypt ratio in duodenum and jejunum of piglets (P 〈 0.05) compared to other two groups at day 7 of the experiment. Feeding diets supplemented with LY and SFY increased (P 〈 0.05) serum concentrations of IgA, IL-2, and IL-6 levels in piglets compared to Control. The CD4+/CD8+ ratio and proliferation of T-lymphocytes in piglets fed diets supplemented with LY were increased compared to that of Control group at day 7 of the experiment (P 〈 0.05). In conclusion, dietary supplementation with both LY and SFY enhanced feed conversion, small intestinal development, and systemic immunity in early-weaned piglets, with better improvement in feed conversion by dietary supplementation with LY, while dietary supplementation with SFY was more effective in increasing systemic immune functions in early-weaned piglets. 展开更多
关键词 growth performance IMMUNITY Intestinal development PIGLETS Saccharomyces cerevisiae YEAST
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Plant growth and their root development after inoculation of arbuscular mycorrhizal fungi in coal mine subsided areas 被引量:19
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作者 Yinli Bi Yanxu Zhang Hui Zou 《International Journal of Coal Science & Technology》 EI 2018年第1期47-53,共7页
Coal mining often cause serious land degradation, soil erosion, and desertification affecting growth of the local vegetation, especially the roots. Arbuscular mycorrhizal fungi (AMF) inoculation is considered a pote... Coal mining often cause serious land degradation, soil erosion, and desertification affecting growth of the local vegetation, especially the roots. Arbuscular mycorrhizal fungi (AMF) inoculation is considered a potential biotechnological tool for mined soil remediation because mycorrhizal fungi could improve plant growth environment, especially under adverse conditions due to their good symbiosis. A field experiment was conducted to study the ecological effects of AMF (Funneliformis mosseae, Rhizophagus intraradices) on the growth of Amygdalus pedunculata Pall. and their root development in the regenerated mining subsidence sandy land. The reclamation experiment included four treatments: inoculation of Funneliformis mosseae (F.m), inoculation of Rhizophagus intraradices (R.i), combined inoculation of F.m and R.i and non-inoculated treatment. Root mycorrhizal colonization, plant height, crown width, soil moisture, root morphology and certain soil properties were assessed. The results showed that AMF improved the shoot and root growth of Amygdalus pedunculata Pall., and significantly increased root colonization after 1 year of inoculation. Available phosphorus content, activities of phosphatase as well as electrical conductivity in soil rhizosphere of all the three inoculation treatments were higher than that of the non-inoculated treatment. AMF increased the quantity of bacteria and fungi in soil rhizosphere compared with the non-inoculated treatment. Our study indicates that revegetation with AMF inoculum could influence plant growth and root development as well as soil properties, suggesting that AMF inoculation can be effective method for further ecological restoration in coal mine subsided areas. 展开更多
关键词 Arbuscular mycorrhizal fungi Plant growth root development Soil remediation Amygdalus pedunculata Pall
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Growth of Young Olive Trees: Water Requirements in Relation to Canopy and Root Development 被引量:1
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作者 Masmoudi-Charfi Chiraz 《American Journal of Plant Sciences》 2013年第7期1316-1344,共29页
The study was carried out in northTunisia(36.5?N, 10.2?E) in order to get a comprehensive view of the growth dynamic of young olive orchards (Olea europaea L.,). The experiment involved irrigated trees of cultivars Ch... The study was carried out in northTunisia(36.5?N, 10.2?E) in order to get a comprehensive view of the growth dynamic of young olive orchards (Olea europaea L.,). The experiment involved irrigated trees of cultivars Chétoui, Manzanille, Meski and Picholine, planted at 6 ×6 m2spacing. Tree height, shoot length and canopy, fruit and trunk diameters were monitored regularly after plantation on 12 trees per variety. Root development was analyzed on Chétoui trees, only. Growth patterns were established annually for each variety before proposing an average model for each growth parameter. Results showed that tree height, shoot length and trunk diameter grew following an S-shaped curve with maximum annual increases occurring on the 4th year for tree height and a year later for canopy. The minimum gain coincided with the highest fruit load year, indicating that competition for assimilates concerns also young trees. Average growth patterns for tree height and shoots showed sustained rates all over the growing season with seven distinct periods of growth. Rapid growth occurred in April, July, and September, with similar growth trends observed for productive and less productive cultivars. However, the studied varieties behaved differently. Picholine cv., provided the most important increases and was the best water user. Results also showed that most roots were confined to the top soil layers and developed nearby the trunks. High root densities and important water depletion were observed in this area and thus, water and fertilizers should be supplied for young trees at these depths and distances from trunks. Root and canopy development were highly correlated (r = 0.94) and interfered with fruit growth. When trees set their first productions, the root-canopy ratio approximated the unit. An optimum ratio between root length and leaf area was found (2.3 km·m?2) for the 6-year-old tree, indicating good equilibrium between the above and the underground parts. On the basis of these results, a mathematical model was developed allowing a precise estimation of water requirements of olive trees during a period, where ground cover rarely exceeds 30%. We can conclude that all these models, graphic and mathematic give precise information on the occurrence of the various phenophases of young olive trees and may be used for a quantitative appraisal of the performance of olive varieties under a given environment. However, some aspects would be probed deeper and particularly the influence of climatic data on growth dynamic. 展开更多
关键词 growth Pattern Phenological Stage OLIVE VARIETY Competition root Density root-Canopy Ratio IRRIGATION Management
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Effects of cyclooxygenase 2 inhibitor on growth-associated protein 43 and nerve growth factor expression in dorsal root ganglion during neuropathic pain development
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作者 Chen Wang Zhenwei Zheng 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第10期749-755,共7页
BACKGROUND: Inflammatory responses in injured nerves have been recognized as important factors for initially sensitizing nociceptive neurons. Cyclooxygenase (COX) is the rate-limiting enzyme in prostaglandin synthe... BACKGROUND: Inflammatory responses in injured nerves have been recognized as important factors for initially sensitizing nociceptive neurons. Cyclooxygenase (COX) is the rate-limiting enzyme in prostaglandin synthesis, and COX-2 inhibitor is involved in mechanisms of analgesia and anti-inflammation. OBJECTIVE: To investigate the effects of COX-2 inhibitor on thermal and mechanical hyperalgesia, as well as expression of growth associated protein 43 (GAP-43) and nerve growth factor (NGF) in dorsal root ganglion, in a rat model of neuropathic pain due to chronic constriction injury. DESIGN, TIME AND SETTING: A randomized, controlled, comparison study that was performed at the Surgical Department and Pathological Laboratory, Second Affiliated Hospital of Shantou University Medical College from September 2006 to September 2007. MATERIALS: COX-2 inhibitor, Iornoxicam, was purchased from Nycomed Pharmaceutical (Austria); rabbit anti-GAP-43, and rabbit anti-NGF polyclonal antibodies were purchased from Boster, Wuhan, China. METHODS: A total of 50 adult, Wistar rats were randomly assigned to four groups: normal control (n = 5), model (n = 15), normal saline control (n = 15), and Iornoxicam treatment (n =15). With exception of the control group, the sciatic nerve of all rats was loosely ligated to establish a model of chronic constriction injury. The model rats were divided into three subgroups according to varying post-operative survival periods: 3, 7 and 14 days (n = 5), respectively. Rats in the Iornoxicam treatment group were intraperitoneally injected with 1.3 mg/kg lornoxicam every 12 hours throughout the entire experimental procedure. Rats in the normal saline control group were intraperitoneally injected with 1.3 mL/kg saline. MAIN OUTCOME MEASURES: Immunohistochemistry revealed expression of GAP-43 and NGF in the L5 dorsal root ganglions. Mechanical withdrawal threshold and thermal withdrawal latency were used to observe neurological behavioral changes in rats. RESULTS: The relative gray values of GAP-43- and NGF-positive neurons in the model group were remarkably increased compared with the normal control rats (P 〈 0.01), while the relative gray values in the Iomoxicam treatment group were significantly less than the model and normal saline control groups (P 〈 0.01). Mechanical withdrawal threshold and thermal withdrawal latency gradually decreased with increasing injury time in the model, normal saline control, and Iornoxicam treatment groups, and were significantly less than the normal control group (P 〈 0.05). In addition, mechanical withdrawal threshold and thermal withdrawal latency were significantly greater in the Iornoxicam treatment group compared with the model and normal saline control groups (P 〈 0.05). CONCLUSION: Intraperitoneal injection of the COX-2 inhibitor Iornoxicam attenuated mechanical and thermal hyperalgesia induced by sciatic nerve chronic constriction injury and inhibited the increased expression of GAP-43 and NGF. 展开更多
关键词 growth associated protein nerve growth factor neuropathic pain cyclooxygenase inhibitor Iomoxicam dorsal root ganglion
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Effects of Nitrate on the Growth of Lateral Root and Nitrogen Absorption in Rice 被引量:14
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作者 王小兵 吴平 +1 位作者 胡彬 陈青爽 《Acta Botanica Sinica》 CSCD 2002年第6期678-683,共6页
Lateral root is primary organ for plant to explore and utilize soil nutrient efficiently. The development of lateral roots (LR) is controlled by both genetic factors and nutrient status in environment. To investigate ... Lateral root is primary organ for plant to explore and utilize soil nutrient efficiently. The development of lateral roots (LR) is controlled by both genetic factors and nutrient status in environment. To investigate the effects of nitrate (NO3-) on rice lateral root growth and nitrogen (N) uptake efficiency under upland condition, three treatments, including root-split culture and whole plant culture in N sufficient and deficient conditions, were used in a vermiculite culture experiment. Root-split treatment showed that the growth of lateral roots was stimulated by localized nitrate supply. However, in whole plant culture, elongation of lateral roots was induced by NO3- deficiency. The effects of NO3- on rice lateral root growth were genotype-dependent. Similar N concentration, soluble sugar concentration and N content in shoot were observed in both root-split treatment and whole plant culture under NO3- sufficient condition, suggesting that the nitrogen requirement for rice normal growth could be satisfied with only half of roots supplied with NO3-. In the root-split treatment, N uptake was positively correlated with the average of lateral root length (ALRL) in NO3--supplied side, suggesting that the ALRL is important for rice root N uptake in the environment where the nitrogen nutrient is limiting factor. No significant correlation was observed between N uptake and ALRL in whole plant culture under N sufficient condition, which implies that the length of lateral roots may not be the main factor to determine tire rice root N uptake in nutrient-rich zone. Morphological and metabolic evidence in this study provided some prospects for genetic improvement of root system characters to improve the efficiency of nutrient absorption in rice. 展开更多
关键词 NO3- lateral root growth nitrogen absorption root-split treatment RICE
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Development and quality of bovine embryos produced in vitro using growth factor supplemented serum-free system
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作者 Arindam Dhali Vahida M. Anchamparuthy +3 位作者 Steve P. Butler Isis K. Mullarky Ronald E. Pearson Frank C. Gwazdauskas 《Open Journal of Animal Sciences》 2011年第3期97-105,共9页
The influence of a growth factor supplemented serum-free system on the development, gene expression, and cryotolerance of in vitro pro- duced bovine embryos was investigated. To assess the embryo development and gene ... The influence of a growth factor supplemented serum-free system on the development, gene expression, and cryotolerance of in vitro pro- duced bovine embryos was investigated. To assess the embryo development and gene ex- pression in blastocysts, abattoir-derived oo- cytes (obtained from 3 - 10 or <3 mm follicles) were matured and fertilized in serum-free media and cultured in synthetic oviductal fluid sup- plemented with fetal bovine serum (FBS, 4%), epidermal growth factor (EGF, 10 ng/mL), insulin like growth factor-1 (IGF-1, 100 ng/mL), stem cell factor (SCF, 50 ng/mL) or combinations of the growth factors. Expressions of selected gene transcripts were relatively quantified in the d 8 blastocysts. To assess the cryotolerance, d 4 morulae (derived from 3 - 10 mm follicles and cultured with the supplementation of FBS or combinations of the growth factors) were vitri- fied, thawed and cultured (with respective sup- plementations). Total cell number and DNA frag- mentation in blastocysts derived from the vitri- fied morulae were assessed through TUNEL assay. The rate (%) of cleavage, blastocyst and expanded/hatched blastocyst did not differ among the culture medium supplementations within the follicle size of 3 - 10 mm (range 65.1 ± 4.3 - 75.4 ± 3.9;22.4 ± 3.9 - 36.4 ± 3.6;and 11.2 ± 2.9 - 23.3 ± 3.2, respectively) or <3 mm (range 59.3 ± 4.2 - 74.5 ± 3.7;15.0 ± 3.5 - 28.7 ± 4.5;and 9.3 ± 2.8 - 17.3 ± 2.7, respectively). Nevertheless, significantly lower (P < 0.05) cleavage and blastocyst rates with FBS and lower blastocyst rate with SCF supplementations were observed for the oocytes derived from <3 compared to 3 - 10 mm follicles. The expression patterns of BCL-2, BAX, HSP1A1, GJA1 and BIRC5 tran- scripts varied significantly (P < 0.05) in all cases, except for BIRC5 in the blastocysts derived from 3 - 10 mm follicles. Following thaw and culture, the development (%) of vitrified morulae into expanded/hatched blastocysts was lower (P < 0.01) with the supplementation of growth fac- tors compared to FBS. In contrast, total number of cells and DNA fragmentation index in blas- tocysts were not different among the treatments. In conclusion, the growth factor supplemented serum-free system was satisfactory for in vitro bovine embryo production. Nevertheless, the system was not efficient when embryos were derived from <3 mm follicles and cultured with SCF. Additionally, gene expression patterns and cryotolerance of the embryos were affected with the treatments of growth factors compared to serum. 展开更多
关键词 IVF growth Factors EMBRYO development Gene Expression CRYOTOLERANCE BOVINE
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