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An unprotected vulnerable relict subtropical conifer-Keteleeria evelyniana: Its forests, populations, growth and endangerment by invasive alien plant species in China
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作者 Cindy Q.Tang Min-Rui Du +10 位作者 Huan-Chong Wang You-Cai Shi Jia-Le Zeng Shu-Li Xiao Peng-Bin Han Jian-Ran Wen Shi-Qian Yao Ming-Chun Peng Chong-Yun Wang Yong-Ping Li Jordi López-Pujol 《Plant Diversity》 SCIE CAS CSCD 2024年第5期648-660,共13页
Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien species.Despite the crucial importance of understan... Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien species.Despite the crucial importance of understanding forest dynamics,knowledge gaps persist,particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria evelyniana.In this study,we investigated the impact of invasive plants on the regeneration of forests dominated by K.evelyniana,a subtropical relict species in southwestern China.For this purpose,we characterized forest dynamics of 160 forest plots featuring K.evelyniana as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of K.evelyniana.We identified four distinct forest types in which K.evelyniana was dominant.We found that radial growth of K.evelyniana trees is faster in younger ageclasses today than it was for older trees at the same age.The population structure of K.evelyniana in each forest type exhibited a multimodal age-class distribution.However,three forest types lacked established saplings younger than 10 years old,a situation attributed to the dense coverage of the invasive alien Ageratina adenophora.This invasive species resulted in a reduction of understory species diversity.Additionally,our analysis uncovered a significant negative correlation in phylogenetic relatedness(net relatedness index)between native and invasive alien plant species in eastern Yunnan.This suggests closely related invasive species face heightened competition,hindering successful invasion.Taken together,our findings indicate that successful establishment and habitat restoration of K.evelyniana seedling/saplings require effective measures to control invasive plants. 展开更多
关键词 Keteleeria evelyniana Age structure Regeneration Species diversity Invasive alien species Phylogenetic relatedness
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Detecting the distribution of and public attitudes to charismatic alien species based on media coverage
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作者 Yuexuan Liu Ruichang Sun +1 位作者 Bo Li Zhijun Ma 《Avian Research》 SCIE CSCD 2024年第3期379-384,共6页
Charismatic species are often reported by the media,providing information for detecting population status and public perception.To identify the number and distribution of free-living Black Swan(Cygnus atratus),a chari... Charismatic species are often reported by the media,providing information for detecting population status and public perception.To identify the number and distribution of free-living Black Swan(Cygnus atratus),a charismatic alien species in Chinese mainland and to detect the public and the media attitudes to the species,we analyzed the reports and emotional tendency from media coverage in 2000-2022 using manual reading,crawler extraction and latent Dirichlet allocation.A total of 6654 Black Swans were reported at 711 sites,including 147 individuals at 30 nature reserves.Successful breeding was reported at one-fourth of the total sites,including five nature reserves.The proportion of positive emotional tendency to Black Swans was overwhelming in the reports and was higher than that to alien species in general,suggesting that the public and the media are unaware of the risk of biological invasion.Effective management of invasive species requires the media clarifies the invasion risk of charismatic alien species.Promoting the unity between the harmfulness of abstract concept of alien species and the charisma of a specific alien species among the public help effective management. 展开更多
关键词 alien species Biological invasion Cygnus atratus Emotional tendency Invasive species Media coverage Public perception
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The Alienation of Nature in Emily Dickinson’s Poems through the Prism of Taoism
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作者 LI Dong-qing 《Journal of Literature and Art Studies》 2024年第3期186-193,共8页
In the poems created by the renowned American poet Emily Dickinson,those related to nature constitute a considerable proportion.However,Dickinson’s attitude toward nature is,in fact,contradictory.On the one hand,Dick... In the poems created by the renowned American poet Emily Dickinson,those related to nature constitute a considerable proportion.However,Dickinson’s attitude toward nature is,in fact,contradictory.On the one hand,Dickinson perceives nature as gentle and kind,akin to a mother.Nature is regarded as“heaven”and embodies harmony.On the other hand,nature possesses its own operational principles and harbors inherent cruelty.According to Dickinson,humans should refrain from excessive interference in the natural order.This article attempts to analyze the similarities in attitude towards nature between Dickinson’s poetry and Taoist philosophy. 展开更多
关键词 Emily Dickinson alienATION NATURE TAOISM
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A Grotesque and Thrilling World:Alienation in The Fluted Girl
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作者 JIN Cheng-xu 《Journal of Literature and Art Studies》 2023年第5期347-351,共5页
As a popular science fiction writer,Paolo Bacigalupi has drawn great attention with his marvelous fictions and novels,yet limited researches have focused on his novels rather than short stories,mostly analyzing from a... As a popular science fiction writer,Paolo Bacigalupi has drawn great attention with his marvelous fictions and novels,yet limited researches have focused on his novels rather than short stories,mostly analyzing from aspects like ecologism,feminism,dystopia,and anthropocene.This paper intends to analyze one of his short fictions,The Fluted Girl,using the theory of alienation to unveil the social problems hidden in the story,in order to further explore the author’s writing intention.In this grotesque and thrilling story world,Bacigalupi shows his ethical concern for the era we are living in,urging the readers to rethink about the alienation in our world. 展开更多
关键词 alienation of people alienation of consumption alienation of technology alienation of aesthetics
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The Alienated Plot in The End of the Road
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作者 王丽娜 《海外英语》 2014年第19期188-190,共3页
The End of the Road is John Barth's second novel, and it is the first novel that brought abortion to the focus of public attention, which proves to be a huge success. This paper intends to study the alienation in ... The End of the Road is John Barth's second novel, and it is the first novel that brought abortion to the focus of public attention, which proves to be a huge success. This paper intends to study the alienation in The End of the Road based on the alienation as a literary style and the alienation embodied in the literary context. Through the analysis of the alienated plot, the paper aims to emphasize the internal cause for the end of the different character's road. 展开更多
关键词 The END of the ROAD alienATION the alienated PLOT
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Using Subtracted AFLP to Efficiently Mark an Alien Chromosome Fragment in Wheat Background 被引量:7
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作者 柴建芳 吴志明 +2 位作者 赵和 Andre LAROCHE 王海波 《Acta Botanica Sinica》 CSCD 2003年第4期379-383,共5页
为解决AFLP中样品间共同片段对多态性片段识别的干扰 ,作者建立了一种“减法AFLP”标记技术 ,并运用这种技术成功对小麦中的外源染色体片段进行了标记。运用该技术 ,样品间的共同扩增片段显著减少 ,在非变性聚丙稀酰胺凝胶上带型差异十... 为解决AFLP中样品间共同片段对多态性片段识别的干扰 ,作者建立了一种“减法AFLP”标记技术 ,并运用这种技术成功对小麦中的外源染色体片段进行了标记。运用该技术 ,样品间的共同扩增片段显著减少 ,在非变性聚丙稀酰胺凝胶上带型差异十分明显 ,多态性片段很容易分辨。其真实性通过将其中两条成功转换成外源染色体片段特异的SCAR标记得到了验证。减法AFLP标记技术的建立为标记作物中的外源染色体片段提供了一种有效手段。 展开更多
关键词 subtracted AFLP subtractive hybridization AFLP alien chromosome fragment WHEAT
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Investigation and Risk Assessment of Alien Invasive Plants in Riparian Zone of Dongjiang River 被引量:2
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作者 付岚 赵鸣飞 +1 位作者 龚玲 刘全儒 《Agricultural Science & Technology》 CAS 2011年第12期1897-1904,共8页
[Objective] The aim was to conduct investigation and risk assessment of the alien invasive plants in riparian zone of Dongjiang River.[Method] The field survey was carried out by the combination methods of sampling pl... [Objective] The aim was to conduct investigation and risk assessment of the alien invasive plants in riparian zone of Dongjiang River.[Method] The field survey was carried out by the combination methods of sampling plots investigation and route survey,and the whole Dongjiang River was covered.52 sampling points were set in the main streams,and 87 sampling points in tributaries streams,624 quadrats were set in total;multi-index comprehensive evaluation method was adopted for the risk assessment with 6 first-level indexes and 25 second-level indexes.[Result] Through the investigation on the riparian zone of Dongjiang River for 2 years,51 species of alien invasive plants were found,belonging to 17 families and 38 genera.The risk level assessment results of these 51 species showed that 18 species,such as Ageratum conyzoides,belonged to high-level risk with over 60 points;26 species,such as Chenopodium ambrosioides,were between 30 and 60 points which belonged to middle-level risk;7 species,such as Paspalum dilatatum,with less than 30 points belonged to low-level risk.[Conclusion] Basic data on the protection,water environmental management and functional zoning of riparian zone of Dongjiang River were provided. 展开更多
关键词 alien invasive plants Dongjiang River Risk assessment Multi-index comprehensive evaluation
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A Study on Alien Invasive Plants from the Interactive Mechanism between Species Niche and Material/Energy Flow 被引量:3
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作者 陈剑 喻庆国 杨宇明 《Agricultural Science & Technology》 CAS 2011年第1期14-19,共6页
[Objective]This study was to reveal the essence of mechanism about how the alien invasive plants spread.[Method]Species niche and material/energy flow were used as basic research indicators to analyze the intrinsic me... [Objective]This study was to reveal the essence of mechanism about how the alien invasive plants spread.[Method]Species niche and material/energy flow were used as basic research indicators to analyze the intrinsic mechanism of alien plants invasion.[Result]Most of the invasive plants have not been explicitly defined and their effective control methods not brought forward.[Conclusion]Overrun of alien invasive plants depends on whether the niche of a species could be continuously met at spatial level.Based on this we put forward corresponding control measures,proposed an assumption to establish a cylinder-network model and discussed the definition of alien invasive plants. 展开更多
关键词 Species niche Material/energy flow alien invasive plants Interactive mechanism
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人类alien基因特性及功能的初步探讨
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作者 彭永德 张新 +3 位作者 宋怀东 胡仁明 韩泽广 陈家伦 《第二军医大学学报》 CAS CSCD 北大核心 2001年第11期1072-1074,共3页
目的 :克隆人 alien基因全长并对其功能作初步探讨。方法 :生物信息学分析、RT- PCR、Northern印迹、GFP表达及酵母双杂交技术。结果 :从人垂体 c DNA文库中克隆到 alien的全长 c DNA,长度 196 3bp,编码 44 3aa。经搜寻 Uni Gene发现其... 目的 :克隆人 alien基因全长并对其功能作初步探讨。方法 :生物信息学分析、RT- PCR、Northern印迹、GFP表达及酵母双杂交技术。结果 :从人垂体 c DNA文库中克隆到 alien的全长 c DNA,长度 196 3bp,编码 44 3aa。经搜寻 Uni Gene发现其定位于染色体 D15 S146 - D15 S117,亚细胞定位为核内。 Northern杂交显示该基因在骨骼肌、心脏及肾脏组织为高表达。半定量 RT- PCR显示在一些内分泌组织均有表达 ,以肾上腺较高。利用酵母双杂交系统显示 alien与甲状腺激素受体 (TR)能相互作用 ,且受 T3 呈剂量依赖方式抑制。 结论 :该基因编码的产物作为一个核蛋白 ,可能参与 展开更多
关键词 alien基因 克隆 甲状腺激素受体 信号转导 基因表达
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Genetic Analysis of Monosomic Alien Addition Line MAAL8 of O. officinalis(CC)-O. sativa(AA)
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作者 刘如亮 刘虹 +2 位作者 陈雁 覃瑞 李刚 《Agricultural Science & Technology》 CAS 2011年第5期702-706,772,共6页
[Objective] By carrying out the anther culture on the monosomic alien addition line MAAL8 of O.officinalis-O.sativa and the back crossing with O.sativa H1493,the genetic characteristics of monosomic alien addition lin... [Objective] By carrying out the anther culture on the monosomic alien addition line MAAL8 of O.officinalis-O.sativa and the back crossing with O.sativa H1493,the genetic characteristics of monosomic alien addition line were studied.[Method] The phenotype analysis was used to study the separation proportion of progeny.Moreover,SSR and the methylation analysis were used to study the transmission behavior of nonhomologous chromosome.[Result] 78 plants of 145 backcross progenies preserved the rolled leaf mark trait of MAAL8.In 32 anther culture plants,five plants had the normal rolled leaves,and two plants had the extremely rolled leaves.The rest had the flat leaves.14 couples of SSR markers were used to analyze,and it indicated that all the rolled-leaf plants could obtain the characteristic band type of O.officinalis,but the flat-leaf plants showed none of them.11 polymorphic RFLP markers were used to carry out Methylation-Sensitive Southern analysis.It showed that the methylation variation manners of eight markers between AA and CC genomes were different.[Conclusion] The nonhomologous chromosome of MAAL8 could pass to the progenies independently and integrally via the meiosis,and the phenotype characteristics didn't change.Moreover,the methylation manner of O.officinalis could inherit stably in the hybrid progeny as the addition of single chromosome.The stability of methylation might have the certain effect on the relatively independent inheritance of nonhomologous chromosome in the genome environment of O.sativa. 展开更多
关键词 Oryza officinalis Monosomic alien addition line Anther culture Methylation variation
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Analysis on the Epidemic Situation of Intercepted Alien Pests from Imported Hides in Hebei and the Countermeasures during 2013-2014
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作者 王建昌 高瑞清 +2 位作者 张帅 王珅 王照华 《Agricultural Science & Technology》 CAS 2015年第9期2007-2010,共4页
The situation of intercepted alien pests from imported hides in Hebei during 2013-2014 was systematically analyzed. The results showed that 163 batches of alien pests were intercepted, including 2 batches of quarantin... The situation of intercepted alien pests from imported hides in Hebei during 2013-2014 was systematically analyzed. The results showed that 163 batches of alien pests were intercepted, including 2 batches of quarantine weeds and they both were Italian cocklebur. According to the statistics of original countries, the intercepted hides from 21 countries all had alien pests, in which Australia was the largest number of batches and species of alien pests. The analysis results showed that there was severe risk in the imported hides carrying alien pests, thus to effectively prevent the invasion of alien pests to our country, several quarantine measures should be taken in the future, such as enhancing the quarantine inspection in ports, and promoting the personnel ability of interception and species identification of alien pests. 展开更多
关键词 Imported hides alien pests Quarantine measures
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A Review of the "Alienation" Theme in Bernard Malamud's Works
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作者 路潇潇 《英语广场(学术研究)》 2012年第6期5-6,共2页
In Bernard Malamud's works,the theme of alienation occurs repeatedly.This article tries to make a review of the "alienation" theme in Malamud's four novels,Dubin's Lives,A New Life,The Tenants,an... In Bernard Malamud's works,the theme of alienation occurs repeatedly.This article tries to make a review of the "alienation" theme in Malamud's four novels,Dubin's Lives,A New Life,The Tenants,and The Fixer. 展开更多
关键词 alienATION Dubin’s Lives A New Life The Tenants The Fixer
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基于Alien阅读器的RFID技术研究
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作者 肖巍 《长春师范学院学报(自然科学版)》 2010年第6期34-37,共4页
本文以Alien阅读器为例研究RFID的相关技术,从阅读器地址查找和自主模式的电子标签阅读两个方面对Alien阅读器的阅读机制进行了深入的研究,实现了基于网络环境下对电子标签进行实时读取及监听。
关键词 RFID alien阅读器 自主模式
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On Adaptation and Alienation in Translation
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作者 周小惠 《海外英语》 2014年第22期173-174,共2页
From cultural point of view,there are two methods in translation:adaptation which is TL culture-oriented and alienation which is SL culture-oriented.What this article tries to prove is that each of them has its own st... From cultural point of view,there are two methods in translation:adaptation which is TL culture-oriented and alienation which is SL culture-oriented.What this article tries to prove is that each of them has its own strong and weak points,which leads to the conclusion that both methods are justified in their existence.And last,some points for attention are suggested for translation,which include the relationship between SL and TL,the type of texts and the translator's purpose. 展开更多
关键词 ADAPTATION alienATION TL SL
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Alienation of the soul ,Interpretation of The love song of J. Alfred Prufrock
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作者 LI Shun-ying 《Sino-US English Teaching》 2009年第10期39-45,共7页
The love song of J. Alfred Prufrock is known as the first masterpiece of modernism poetry. Its protagonist Prufrock is not a concrete single person, but an abstraction of all modem men in trouble. He is alienated by w... The love song of J. Alfred Prufrock is known as the first masterpiece of modernism poetry. Its protagonist Prufrock is not a concrete single person, but an abstraction of all modem men in trouble. He is alienated by women, time and space, and hence he is paralyzed and helpless. The use of dramatic monologue and stream of consciousness, quotation and allusions, objective correlative and startling imagery, irony and anti-climax, refrain and rhythm, fragmentation and juxtaposition not only deepens the theme, but also establishes Eliot's reputation as a leading modernist poet. 展开更多
关键词 The love song of J. Alfred Prufrock theme alienation of the soul techniques expressing the alienation
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The Alienation and Loneliness in Orpheus Descending
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作者 陈瑶琼 《海外英语》 2016年第23期164-165,共2页
Orpheus Descending is written by American famous playwright Tennessee Williams. According to the portrayal of a series marginalized people, this drama presents the solitude in human beings' heart and the estrangem... Orpheus Descending is written by American famous playwright Tennessee Williams. According to the portrayal of a series marginalized people, this drama presents the solitude in human beings' heart and the estrangement in interpersonal relations. This paper tries to analyze the solitude theme in this drama from philosophic aspect and realistic aspect, combining alienation theory and existentialism theory to analyze the reason and the manifestation of solitude. 展开更多
关键词 alienATION LONELINESS Orpheus Descending
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Death of Children:Aloofness,Alienation and Self-Alienation in Jude the obscure
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作者 侯立志 《海外英语》 2017年第16期156-157,164,共3页
The aim of this paper is to display Thomas Hardy's outlook on alienation in his Jude the obscure. In the deconstruction of the novel, the theme of alienation and self-alienation, together with the aloofness in soc... The aim of this paper is to display Thomas Hardy's outlook on alienation in his Jude the obscure. In the deconstruction of the novel, the theme of alienation and self-alienation, together with the aloofness in society are brought to the fore, by which Thomas Hardy's viewpoints on alienation in his philosophy of life is derived. 展开更多
关键词 alienATION SELF-alienATION Jude the obscure
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Effect of an Alien Species Spartina alterniflora Loisel on Biogeochemical Processes of Intertidal Ecosystem in the Jiangsu Coastal Region,China 被引量:24
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作者 ZHOU Hong-Xia LIU Jin-E +1 位作者 ZHOU Jun QIN Pei 《Pedosphere》 SCIE CAS CSCD 2008年第1期77-85,共9页
Spartina alterniflora Loisel, a species vegetating in intertidal flats along the eastern coast of the United States, was introduced in China almost 30 years ago and has become an urgent topic due to its invasiveness i... Spartina alterniflora Loisel, a species vegetating in intertidal flats along the eastern coast of the United States, was introduced in China almost 30 years ago and has become an urgent topic due to its invasiveness in the coastal zone of China. The impacts of this alien species S. alterniflora on intertidal ecosystem processes in the Jiangsu coastland were investigated by comparing the sediment nutrient availability and trace element concentration characteristics in a mud flat and those of a four-year old Spartina salt marsh that had earlier been a mudflat. At each study site, fifteen plots were sampled in different seasons to determine the sediment characteristics along the tidal flats. The results suggested that Spartina salt marsh sediments had significantly higher total N, available P, and water content, but lower pH and bulk density than mudflat sediments. Sediment salinity, water content, total N, organic C, and available P decreased along a seaward gradient in the Spartina salt marsh and increased with vegetation biomass. Furthermore, the concentrations of trace elements and some metal elements in the sediment were higher under Spartina although these increases were not significant. Also, in the Spartina marsh, some heavy metals were concentrated in the surface layer of the sediment. The Spartina salt marsh in this study was only four years old; therefore, it is suggested that further study of this allen species on a longer time frame in the Jiangsu coastland should be carried out. 展开更多
关键词 alien species biogeochemical processes intertidal ecosystem salt marsh Spartina alterniflora Loisel
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A risk assessment system for alien plant bio-invasion in Xiamen,China 被引量:10
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作者 Desmond K.O'TOOLE 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第8期989-997,共9页
Bio-invasion has caused serious ecosystem damage and enormous economic losses in China,and it has been the greatest factor to island bio-diversity reduction.Xiamen,as an important seaport with a relatively high conser... Bio-invasion has caused serious ecosystem damage and enormous economic losses in China,and it has been the greatest factor to island bio-diversity reduction.Xiamen,as an important seaport with a relatively high conservation value,is particularly vulnerable to bio-invasion for its typical island ecosystem as well as frequent human-made disturbance.As a result of field surveys,literature review, and consultation with experts,a list of 67 alien plants identified as major invaders(12 species)and emerging invade... 展开更多
关键词 bio-invasion invasive species alien plants risk assessment
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Study on the Allelopathic Effects of Alien Invasive Species Cenchrus echinatus on Seed Germination and Seedling Growth of Solanaceae Crops
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作者 马婉捷 缪绅裕 +4 位作者 陶文琴 许镇健 王厚麟 陈健辉 黄丽宜 《Agricultural Science & Technology》 CAS 2014年第6期885-889,共5页
[Objective] This study aimed to investigate the potential ecological dam- ages of alien invasive species Cenchrus echinatus. [Method] By using seed germi- nation method, the effects of different concentrations of C. e... [Objective] This study aimed to investigate the potential ecological dam- ages of alien invasive species Cenchrus echinatus. [Method] By using seed germi- nation method, the effects of different concentrations of C. echinatus aqueous extracts on seed germination and seedling growth of three Solanaceae crops were investigated. [Result] After incubated for 5 d, no significant differences were observed in germination speed indices of Lycopersicum esculentum seeds between aqueous extract groups and control groups; germination speed indices of Solarium melongena seeds were significantly reduced with the increasing concentration of Cenchrus echinatus aqueous extracts; however, Capsicum frutescens seeds in various groups were not germinated. After incubated for 7 d, root lengths of Lycopersicum esculentum seedlings were inhibited with the increasing concentration of Cenchrus echinatus aqueous extracts, while stem lengths and comprehensive allelopathic effects were promoted; germination rates of Solanum melongena seeds in various groups were all significantly lower than control groups; root length, stem length and comprehen- sive allelopathic effects in higher concentration groups were inhibited; germination rates of Capsicum frutescens seeds were significantly inhibited, and those in the highest concentration group were not generated. After incubated for 14 d, all indica- tors of Solanum melongena were significantly inhibited; various indicators of Capsicum frutescens in the highest concentration group were significantly inhibited. [Conclusion] The sensitivity of three Solanaceae crops to Cenchrus echinatus aqueous extracts presented an overall order of Solanum melongena 〉 Capsicum frutescens 〉 Lycopersicum esculentum, suggesting that Cenchrus echinatus can to some extent inhibit the growth of several crops, which should be strictly prevented and controlled in agricultural production. 展开更多
关键词 Cenchrus echinatus Allelopathic effect alien invasive plant SOLANACEAE CROPS
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