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Wood forming tissue-specific expression of PaTyDC4 promotes xylem differentiation and lignin deposition during secondary growth and confers drought tolerance in Populus
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作者 Qiao Wang Yiqing Wang +5 位作者 Xintong Lu Yang Chen Yan Chen Xiuwen Wu Gongke Zhou Guohua Chai 《Horticultural Plant Journal》 2025年第2期854-864,共11页
Tyrosine decarboxylase(TyDC)converts tyrosine to tyramine and plays a crucial role in secondary metabolite reactions,development,and stress responses in plants.Currently,the biological role of TyDC proteins from trees... Tyrosine decarboxylase(TyDC)converts tyrosine to tyramine and plays a crucial role in secondary metabolite reactions,development,and stress responses in plants.Currently,the biological role of TyDC proteins from trees is unknown.This study provided evidence showing that poplar PaTyDC4 functions in wood development and drought stress response.PaTyDC4 is preferentially expressed in wood-forming cells in stems.Overexpression of PaTyDC4 in poplars under the control of a xylem-specific promoter resulted in an increase in the ratio of xylem to phloem width,vessel cell area,and lignin accumulation in the stems.Biochemical assays revealed that PaTyDC4 was a component of the PaC3H17-PaMYB199 module-mediated pathway.In poplar stems,Pa TyDC4 expression was directly suppressed by PaMYB199,which was attenuated by the interaction between PaC3H17 and PaMYB199.In addition,Pa TyDC4 overexpression lines showed stronger drought tolerance than the wild-type lines,with higher photosynthetic capacity and lower levels of H_(2)O_(2).These results indicate that PaTyDC4 promotes xylem differentiation and lignin deposition during secondary growth and confers drought tolerance.Our findings may be useful for the genetic modification of biomass and drought resistance in trees. 展开更多
关键词 populus Tyrosine decarboxylase XYLEM LIGNIN Drought stress Cell wall
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Hybrid ecophysiological growth model for deciduous Populus tomentosa plantation in northern China
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作者 Serajis Salekin Mark Bloomberg +4 位作者 Benye Xi Jinqiang Liu Yang Liu Doudou Li Euan G.Mason 《Forest Ecosystems》 2025年第1期112-120,共9页
Short rotation plantation forestry(SRF)is being widely adopted to increase wood production,in order to meet global demand for wood products.However,to ensure maximum gains from SRF,optimised management regimes need to... Short rotation plantation forestry(SRF)is being widely adopted to increase wood production,in order to meet global demand for wood products.However,to ensure maximum gains from SRF,optimised management regimes need to be established by integrating robust predictions and an understanding of mechanisms underlying tree growth.Hybrid ecophysiological models,such as potentially useable light sum equation(PULSE)models,are useful tools requiring minimal input data that meet the requirements of SRF.PULSE models have been tested and calibrated for different evergreen conifers and broadleaves at both juvenile and mature stages of tree growth with coarse soil and climate data.Therefore,it is prudent to question:can adding detailed soil and climatic data reduce errors in this type of model?In addition,PULSE techniques have not been used to model deciduous species,which are a challenge for ecophysiological models due to their phenology.This study developed a PULSE model for a clonal Populus tomentosa plantation in northern China using detailed edaphic and climatic data.The results showed high precision and low bias in height(m)and basal area(m^(2)·ha^(-1))predictions.While detailed edaphoclimatic data produce highly precise predictions and a good mechanistic understanding,the study suggested that local climatic data could also be employed.The study showed that PULSE modelling in combination with coarse level of edaphic and local climate data resulted in reasonably precise tree growth prediction and minimal bias. 展开更多
关键词 Growth-yield model populus species Hybrid ecophysiological modelling Deciduous trees PHENOLOGY
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Zero-valent silver nanoparticles functionalized populus tomentosa fiber for efficient capture and immobilization of iodine vapor
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作者 Yu Fang Hui Zhu +5 位作者 Pei Chen Fang Liu Yong Yi Jian Zhou Tao Duan Jie-Hong Lei 《Nuclear Science and Techniques》 2025年第5期43-56,共14页
With the rapid development of nuclear energy,the removal of radioactive iodine generated during spent fuel reprocessing has become increasingly important.Based on the unique straw-like structure of populus tomentosa f... With the rapid development of nuclear energy,the removal of radioactive iodine generated during spent fuel reprocessing has become increasingly important.Based on the unique straw-like structure of populus tomentosa fiber(PTF)and the highly active iodine vapor capture ability of zero-valent silver nanoparticles(PTF@Ag^(0)NP),an Ag^(0)NP composite functional material with highly efficient iodine vapor capture capability was synthesized from biowaste PTF through ultrasonic and hightemperature hydrothermal methods in this study.The iodine capture experiment demonstrated that PTF@Ag^(0)NP exhibits rapid iodine capture efficiency,reaching dynamic equilibrium within 4 h and a maximum capture capacity of 1008.1 mg/g.Density functional theory calculations show that PTF@Ag^(0)NP exhibits extremely high chemical reactivity toward iodine,with a reaction binding energy of-2.88 e V.Additionally,the molecular dynamics of PTF@Ag^(0)NP indicate that there is no atomic displacement at 77?C,indicating the excellent temperature stability of the material at the operating temperature.The capture mechanism suggests that iodine vapor primarily reacts with Ag^(0)NP to form Ag I,and that the hydroxyl groups in PTF can also effectively capture iodine vapor by adsorption induction.In conclusion,PTF@Ag^(0)NP is expected to be an effective candidate adsorbent material for removing radioactive iodine vapor from exhaust gases during spent fuel reprocessing. 展开更多
关键词 Ag^(0)NP populus tomentosa fiber Iodine vapor Capture and immobilization DFT calculations
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Promotion of biomass, photosynthesis, and root growth of seedling biomass, photosynthesis, and root growth of Populus davidiana × P. bolleana by two species of ectomycorrhizal fungi 被引量:1
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作者 Tianze Zhang Fanjun Meng Dachuan Yin 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期306-316,共11页
The addition of ectomycorrhizal fungi(ECMF),beneficial rhizosphere microorganisms,to the soil can pro-mote plant growth and resistance.Here,Populus davidi-ana×Populus bolleana tissue culture seedlings were grown ... The addition of ectomycorrhizal fungi(ECMF),beneficial rhizosphere microorganisms,to the soil can pro-mote plant growth and resistance.Here,Populus davidi-ana×Populus bolleana tissue culture seedlings were grown for 3 months in soils inoculated with one of the species,then seedlings were assessed for mycorrhizal colonization rate and growth,physiological and root traits.Suillus luteus and Populus involutus each formed ectomycorrhizal associa-tions with the seedlings.Seedling height,ground diameter,biomass,and leaf area were significantly greater after treat-ment with ECMF than in the non-inoculated controls.Treat-ment improved all physiological and root variables assessed(chlorophylls and carotenoids,cellulose,and soluble sugars and proteins;root length,surface area,projected area,mean diameter,volume,number of root tips).Seedlings inocu-lated with S.luteus outperformed those inoculated with P.involutus. 展开更多
关键词 Ectomycorrhizal association Suillus luteus Paxillus involutus populus davidiana×P.bolleana Growth promotion Root system scan
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Analysis of genes related to xylem cell wall development based on transcriptomics in Populus alba ‘Berolinensis’ tension wood
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作者 Lin Feng Youchao He +2 位作者 Xu Li Meiqi Zhou Chao Wang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期328-343,共16页
Populus alba‘Berolinensis’is a fast-growing,high-yielding species with strong biotic and abiotic stress resistance,and widely planted for timber,shelter belts and aesthetic purposes.In this study,molecular developme... Populus alba‘Berolinensis’is a fast-growing,high-yielding species with strong biotic and abiotic stress resistance,and widely planted for timber,shelter belts and aesthetic purposes.In this study,molecular development is explored and the important genes regulating xylem forma-tion in P.alba‘Berolinensis’under artificial bending treat-ments was identified.Anatomical investigation indicated that tension wood(TW)was characterized by eccentric growth of xylem and was enriched in cellulose;the degree of ligni-fication was lower than for normal wood(NW)and oppo-site wood(OW).RNA-Seq-based transcriptome analysis was performed using developing xylem from three wood types(TW,OW and NW).A large number of differentially expressed genes(DEGs)were screened and 4889 counted.In GO and KEGG enrichment results,genes involved in plant hormone signal transduction,phenylpropanoid biosynthesis,and cell wall and secondary cell wall biogenesis play major roles in xylem development under artificial bending.Eight expansin(PalEXP)genes were identified from the RNA-seq data;four were differentially expressed during tension wood formation.Phylogenetic analysis indicated that PalEXLB1 belongs to the EXPB subfamily and that the other PalEXPs are members of the EXPA subfamily.A transcriptional regulatory network construction showed 10 transcription factors located in the first and second layers upstream of EXP,including WRKY,ERF and bHLH.RT‒qPCR analy-sis in leaves,stems and roots combined with transcriptome analysis suggests that PalEXPA2,PalEXPA4 and PalEXPA15 play significant regulatory roles in cell wall formation during tension wood development.The candidate genes involved in xylem cell wall development during tension wood formation marks an important step toward identifying the molecular regulatory mechanism of xylem development and wood property improvement in P.alba‘Berolinensis’. 展开更多
关键词 populus alba‘Berolinensis’ Tension wood Differentially expressed genes Expansin proteins
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Impacts of Defoliation on Morphological Characteristics and Non-Structural Carbohydrates of Populus talassica × Populus euphratica Seedlings
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作者 Mengxu Su Zhanjiang Han +2 位作者 Zhen Zhao Xiaofeng Wu Jiaju Wu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第7期1689-1703,共15页
Leaves are important‘source’organs that synthesize organic matter,providing carbon sources for plant growth.Here,we used Populus talassica×Populus euphratica,the dominant species in ecological and timber forest... Leaves are important‘source’organs that synthesize organic matter,providing carbon sources for plant growth.Here,we used Populus talassica×Populus euphratica,the dominant species in ecological and timber forests,to simulate carbon limitation through artificial 25%,50%,and 75%defoliation treatments and explore the effects on root,stem,and leaf morphology,biomass accumulation,and carbon allocation strategies.At the 60th d after treat-ment,under 25%defoliation treatment,the plant height,specific leaf weight,root surface area and volume,and concentrations of non-structural carbohydrates in stem and root were significantly increased by 9.13%,20.00%,16.60%,31.95%,5.12%,and 9.34%,respectively,relative to the control.There was no significant change in the growth indicators under 50%defoliation treatment,but the concentrations of non-structural carbohydrates in the leaf and stem significantly decreased,showing mostly a negative correlation between them.The opposite was observed in the root.Under 75%defoliation treatment,the plant height,ground diameter,leaf number,single leaf area,root,stem,and total biomass were significantly reduced by 14.15%,10.24%,14.86%,11.31%,11.56%,21.87%,and 16.82%,respectively,relative to the control.The concentrations of non-structural carbohydrates in various organs were significantly reduced,particularly in the consumption of the starch concentrations in the stem and root.These results indicated that carbon allocation strategies can be adjusted to increase the con-centration of non-structural carbohydrates in root and meet plant growth needs under 25%and 50%defoliation.However,75%defoliation significantly limited the distribution of non-structural carbohydrates to roots and stems,reduced carbon storage,and thus inhibited plant growth.Defoliation-induced carbon limitation altered the carbon allocation pattern of P.talassica×P.euphratica,and the relationship between carbon reserves in roots and tree growth recovery after defoliation was greater.This study provides a theoretical basis for the comprehen-sive management of P.talassica×P.euphratica plantations,as well as a reference for the study of plantation car-bon allocation strategies in the desert and semi-desert regions of Xinjiang under carbon-limitation conditions. 展开更多
关键词 populus talassica×populus euphratica DEFOLIATION carbon limitation carbon allocation non-structural carbohydrates
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地下水位对胡杨(Populus euphratica)和灰胡杨(Populus pruinosa)叶绿素荧光光响应与光合色素含量的影响 被引量:26
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作者 王海珍 陈加利 +2 位作者 韩路 徐雅丽 贾文锁 《中国沙漠》 CSCD 北大核心 2013年第4期1054-1063,共10页
在塔里木河上游利用便携式调制叶绿素荧光仪研究了地下水位对胡杨(Populus pruinosa)和灰胡杨(Popu-lus pruinosa)光合色素和叶绿素荧光光响应的影响。结果表明:不同地下水位环境下,2树种表观光合电子传递速率(ETR)、非光化学猝灭系数(N... 在塔里木河上游利用便携式调制叶绿素荧光仪研究了地下水位对胡杨(Populus pruinosa)和灰胡杨(Popu-lus pruinosa)光合色素和叶绿素荧光光响应的影响。结果表明:不同地下水位环境下,2树种表观光合电子传递速率(ETR)、非光化学猝灭系数(NPQ)、PSⅡ激发能压力(1-qP)、天线色素热耗散能量(D)、非光化学反应耗散能量(E)、光合功能相对限制值(PED)和光系统间激发能分配不平衡偏离系数(β/α-1)随光合有效辐射(PAR)增加而升高,PSⅡ实际光化学效率(ΦPSⅡ)、光化学猝灭系数(qP)和光化学反应能量(P)则随PAR增加而降低;相同光强下,地下水位下降导致胡杨和灰胡杨叶片含水量、最大电子传递速率(ETRmax)、光化学反应启动速率(θ)、ETR、ΦPSⅡ、qP、P与叶绿素(Chla、Chlb、Chl(a+b))和类胡萝卜素(Car)含量降低,而使Chla/b、NPQ、D、E、PED、1-qP、β/α-1明显升高;地下水位下降显著影响2树种叶绿素荧光光响应参数,引起光能吸收、传递与分配改变,致使光合效率降低;地下水位下降对灰胡杨光合生理过程的影响程度明显高于胡杨,表明胡杨对荒漠逆境的适应性强于灰胡杨。逆境下胡杨通过维持相对较高的ETR、ETRmax、θ、ΦPSⅡ、qP、P值,并通过增强非辐射性热耗散来调节自身能量代谢,以此来保护光合机构正常运转,这是胡杨长期适应干旱荒漠逆境而形成的一种自我调节机制。 展开更多
关键词 胡杨(populus euphratica) 灰胡杨(populus pruinosa) 地下水位 光合色素 叶绿素荧光 光响应曲线
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Comprehensive Overview of Populus simonii Research in the Recent Years
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作者 Dandan Zhang Faujiah Nurhasanah Ritonga +5 位作者 Tuya Siqin Runxian Song Zicheng Zhang Mingwei Tang Peilin Sun Wa Gao 《Open Journal of Ecology》 2024年第5期419-434,共16页
As an important ecological tree species in northern China, Populus simonii plays a crucial role in maintaining ecological balance and promoting environmental sustainability. The academic community has conducted a seri... As an important ecological tree species in northern China, Populus simonii plays a crucial role in maintaining ecological balance and promoting environmental sustainability. The academic community has conducted a series of in-depth studies on this species, covering key areas such as genomics, survival mechanisms, and genetic breeding. Through the analysis of the genomic structure and function of P. simonii, we have not only revealed the molecular basis for its adaptation to harsh environments but also identified key genes that promote its growth and resistance to pests and diseases. Furthermore, exploring the survival mechanisms of P. simonii has deepened our understanding of its stress resistance traits, including how it effectively copes with abiotic stresses such as drought, salinization, and heavy metal pollution. In genetic breeding, significant progress has been made through the application of modern biotechnology, improving the growth rate and wood quality of P. simonii and enhancing its environmental adaptability and disease resistance. These research findings have not only enriched our knowledge of the biological characteristics of P. simonii but also provided a solid scientific foundation for its application in ecological restoration, forestry production, and environmental management. 展开更多
关键词 BREEDING Ecological Restoration GENOMICS populus simonii Resistance Mechanisms
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胡杨(Populus euphraticu)与灰胡杨(Populus pruinosa)种子萌发对不同盐类胁迫的响应 被引量:11
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作者 王海珍 韩路 贾文锁 《中国沙漠》 CSCD 北大核心 2013年第3期743-750,共8页
将塔里木荒漠优势种——胡杨(Populus euphraticu)和灰胡杨(Populus pruinosa)的种子置于8种浓度的NaCl(单盐)和土盐(复合盐)溶液中进行发芽实验,探讨两树种种子对不同盐类的耐受限度和适应萌发生境,采用隶属函数法综合评价其耐盐性。... 将塔里木荒漠优势种——胡杨(Populus euphraticu)和灰胡杨(Populus pruinosa)的种子置于8种浓度的NaCl(单盐)和土盐(复合盐)溶液中进行发芽实验,探讨两树种种子对不同盐类的耐受限度和适应萌发生境,采用隶属函数法综合评价其耐盐性。结果表明:两树种种子发芽率、相对发芽率、发芽势、发芽指数和子叶展平率均随NaCl浓度的增加而下降,相对盐害率升高。二者种子相对发芽率在浓度<0.4%的NaCl溶液中均超过75%,NaCl胁迫下2种种子发芽率无显著差异(p>0.05)。单盐处理下胡杨种子的各项发芽指标均优于灰胡杨,表明胡杨的耐盐(NaCl)能力强于灰胡杨。低浓度土盐溶液对二者种子萌发均具有促进作用,发芽率和发芽指数明显升高,而高浓度土盐溶液则抑制种子萌发。二者种子相对发芽率在浓度<0.8%的土盐溶液中均超过80%,且1.6%盐浓度下仍高于20%,此值远高于NaCl胁迫。土盐处理下两树种种子发芽率差异达极显著水平(p<0.01)。土盐处理下灰胡杨种子的各项发芽指标均优于胡杨,表明灰胡杨对土盐具有较强的适应性和耐盐能力。NaCl胁迫对二者种子萌发的抑制作用大于土盐。胡杨、灰胡杨均具有较强的耐盐性,但早期低盐条件是两树种幼苗建立的关键。 展开更多
关键词 胡杨(populus euphraticu) 灰胡杨(populus pruinosa) 盐胁迫 种子萌发 耐盐阈值
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Integrative Analysis of the Transcriptome and Metabolome of Poplar,Populus deltoides‘Shalinyang’.(Salicaceae),Reveals Responses to Attack by Anoplophora glabripennis(Coleoptera)
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作者 Jiayu Luo Jianfeng Liu +7 位作者 Zuoxiang Sun Pengpeng Shao Danyang Wang Jianzhong Yao Binzhou Li Lijun Dong Dandan Cao Jianrong Wei 《Phyton-International Journal of Experimental Botany》 2024年第9期2167-2188,共22页
Anoplophora glabripennis is one of the most devastating wood-boring beetles that attacks poplars.However,one poplar species,Populus deltoides,has strong resistance to Anoplophora glabripennis infestation,the underlyin... Anoplophora glabripennis is one of the most devastating wood-boring beetles that attacks poplars.However,one poplar species,Populus deltoides,has strong resistance to Anoplophora glabripennis infestation,the underlying defense mechanisms against Anoplophora glabripennis are poorly understood.Secondary metabolites play a crucial role in plants to combat biological stress.Here,based on transcriptome and metabolome,we demonstrated that the mechanisms for responses to mechanical damage and insect infestation were different.The degree of reactions to adult groove production,larval incubation,and larval frass production was not identical.In addition,the potential genes with insect resistance activity were identified.Predominant differentially expressed genes(DEGs)found in the phloem of Populus deltoides include anthocyanidin 3-O-glucosyltransferase5(PdUGT72E),peroxidase 73(PdPod73),peroxidase A2(PdPodA2)and macrophage migration inhibitory factor(PdMIF)responded to stress caused by Anoplophora glabripennis,which further resulted in activation of the plant defense system against insects via changes in regulation of metabolic pathways,such as tyrosine metabolism pathway,phenylpropanoid biosynthesis pathway and flavonoid biosynthesis pathway.Therefore,this work has laid a foundation for further unraveling the mechanisms involved in this interaction. 展开更多
关键词 populus deltoides‘Shalinyang’ Anoplophora glabripennis transcriptome and metabolome defense response
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Extraction of Total DNA from Populus euphratica Oliv. and Populus pruinosa Schrenk. by Improved CTAB Method 被引量:1
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作者 司杰 黄文娟 焦培培 《Agricultural Science & Technology》 CAS 2016年第4期826-828,832,共4页
This study presented an improved CTAB method for extracting DNA from leaves of Populus euphratica Oliv. and Populus pruinosa Schrenk. based on the conventional CTAB method. The results showed that preventing DNA from ... This study presented an improved CTAB method for extracting DNA from leaves of Populus euphratica Oliv. and Populus pruinosa Schrenk. based on the conventional CTAB method. The results showed that preventing DNA from browning is a key step to obtain the high-quality DNA during DNA extraction, and under the condition of grinding in the presence of liquid nitrogen, adding such three antioxidants as PVP dry powder, Vc and β-mercaptoethanol could prevent DNA from browning effectively. The total DNA extracted by the improved CTAB method was subjected to PCR detection which proved that it totally satisfied the requirements of subsequent study. 展开更多
关键词 populus euphratica Oliv. populus pruinosa Schrenk. BROWNING Total DNA Polymerase chain reaction(PCR)
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Wood Physical and Mechanical Properties of Populus × canadensis Moench and Populus ×euramericana(Dode) Guinier cv. Gelrica
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作者 张英杰 冯德君 窦延光 《Agricultural Science & Technology》 CAS 2017年第12期2532-2535,共4页
The physical-mechanical properties of Populus x canadensis Moench and Populus x euramericana (Dode) Guinier cv. Gelrica were studied to provide theoret- ical and scientific bases for the directional breeding and eff... The physical-mechanical properties of Populus x canadensis Moench and Populus x euramericana (Dode) Guinier cv. Gelrica were studied to provide theoret- ical and scientific bases for the directional breeding and efficient use of artificial forests with P. canadensis and P. euramericana Gelrica. The results showed the air-dried density, basic density of P. canadensis were 0.468 g/cm3 and 0.372 g/cm3, respectively; the shrinkage coefficient of radial, tangential and volume were 0.133%, 0.270% and 0.553%, respectively;the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain were 9 302.99 MPa, 79.69 MPa and 40.32 Mpa, respectively. As for the P. euramericana Gelrica, the air-dried density, basic densitywere 0.453 and 0.355 g/cm3, respectively; the shrink- age coefficient of radial, tangential and volume were 0.205%, 0.304% and 0.554%, respectively; the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain were 9 014.44, 55.87 and 33.09 Mpa respectively. Comprehensive analysis of the indicators showed that the properties of P. canadensis were better than those of P.euramericana Gelrica. 展开更多
关键词 populus x canadensis Moench populus x euramericana (Dode) Guiniercv. Ge/rica Physical properties Mechanical properties
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胡杨(Populus euphratica)树干液流特征及其与环境因子的关系 被引量:56
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作者 赵春彦 司建华 +2 位作者 冯起 鱼腾飞 李炜 《中国沙漠》 CSCD 北大核心 2014年第3期718-724,共7页
以2012年4—10月实测数据,对黑河下游胡杨树干液流特征及其与环境因子的关系进行了分析。结果表明:在整个生长季,胡杨(Populus euphratica)树干液流速率日变化具有明显的昼夜节律性,夜间存在明显的树干液流以补充白天蒸腾损失的大量水分... 以2012年4—10月实测数据,对黑河下游胡杨树干液流特征及其与环境因子的关系进行了分析。结果表明:在整个生长季,胡杨(Populus euphratica)树干液流速率日变化具有明显的昼夜节律性,夜间存在明显的树干液流以补充白天蒸腾损失的大量水分,恢复植物体内的水分平衡;与其他天气条件下树干液流速率特征比较,阴雨天液流启动时间推迟,液流停止时间提前,液流历时缩短,且峰值显著缩小;树干液流的季节变化特征表现为液流速率在夏季的启动时间、到达峰值的时间、液流停止时间均早于春季和秋季;单株蒸腾耗水表现出明显的季节性格局,4月和10月中下旬耗水量较低,5—8月为主要耗水期,占整个生长季的75%;日间液流速率主要受到土壤含水量、水汽压差、光合有效辐射、相对湿度和气温的影响,夜间液流速率主要受到水汽压差、相对湿度的影响,整个生长季胡杨树干液流主要受光合有效辐射、土壤水分、气温和相对湿度的影响。 展开更多
关键词 树干液流 环境因子 关系模型 黑河 胡杨(populus euphratica)
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荒漠河岸胡杨(Populus euphratica)树干液流的时滞效应 被引量:18
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作者 赵春彦 司建华 +3 位作者 冯起 常宗强 鱼腾飞 李炜 《中国沙漠》 CSCD 北大核心 2014年第5期1254-1260,共7页
以2012年4—9月树干液流速率与环境因子的实测数据,分析了荒漠河岸胡杨(Populus euphratica)树干液流的时滞效应。结果表明:不同月份胡杨树干液流速率对不同环境因子的时滞不同;4—9月,胡杨树干液流速率峰值时间比太阳辐射峰值时间晚约... 以2012年4—9月树干液流速率与环境因子的实测数据,分析了荒漠河岸胡杨(Populus euphratica)树干液流的时滞效应。结果表明:不同月份胡杨树干液流速率对不同环境因子的时滞不同;4—9月,胡杨树干液流速率峰值时间比太阳辐射峰值时间晚约1h,比空气温度峰值时间早约1h,比水汽压差峰值时间早约2h,比空气相对湿度谷值时间早约2h;对影响胡杨树干液流速率的环境因子进行了主成分分析,发现胡杨树干液流速率与1h以前的第1主成分、第2主成分相关性最高,相关系数分别为0.864、0.875;对错位前后胡杨树干液流速率与环境因子进行多元线性回归分析发现,在胡杨树干液流的数值模拟中,考虑液流相对于环境因子的时滞效应可以提高模型的拟合精度。 展开更多
关键词 热比率法 荒漠河岸林 胡杨(populus euphratica) 时滞效应
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Cloning of cDNA Encoding CCoAOMT from Populus tomentosa and Down-regulation of Lignin Content in Transgenic Plant Expressing Antisense Gene 被引量:22
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作者 魏建华 赵华燕 +2 位作者 张景昱 刘惠荣 宋艳茹 《Acta Botanica Sinica》 CSCD 2001年第11期1179-1183,共5页
cDNA encoding caffeoyl CoA O-methyltransferase (CCoAOMT) from Chinese white poplar ( Populus tomentosa Carr.) was cloned by RT-PCR and sequenced. Northern analysis displayed that the CCoAOMT was expressed specifically... cDNA encoding caffeoyl CoA O-methyltransferase (CCoAOMT) from Chinese white poplar ( Populus tomentosa Carr.) was cloned by RT-PCR and sequenced. Northern analysis displayed that the CCoAOMT was expressed specifically in the developing secondary xylem and its expression was coincident with lignification. The antisense CCoAOMT cDNA was transformed into P. tremula x P. alba mediated by Agrobacterium tumefaciens ( Smith et Townsend) Conn. Transgenic plants were identified with PCR, PCR-Southern and Southern analysis. Lignin content in 5- to 6-month-old transgenic plants was measured. One of the transgenic lines had significant reduction of 17.9% in Klason lignin content as compared with that of untransformed poplar. The results demonstrate that antisense repression of CCoAOMT is an efficient way to reduce lignin content for improving pulping property in engineered trees. 展开更多
关键词 RT-PCR populus tomentosa CCOAOMT antisense RNA LIGNIN
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塔里木河下游胡杨(Populus euphratica)地上生物量估测 被引量:18
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作者 董道瑞 李霞 +1 位作者 万红梅 林海军 《中国沙漠》 CSCD 北大核心 2013年第3期724-730,共7页
根据塔里木河下游英苏至喀尔达依区段距离河流50~300m的80个胡杨(Populus euphratica)一级枝生物量实测数据,采用数理统计方法构建胡杨一级枝和树冠生物量估测模型,在精度检验基础上筛选出最佳模型,并对其估测值与实测值进行卡方检验... 根据塔里木河下游英苏至喀尔达依区段距离河流50~300m的80个胡杨(Populus euphratica)一级枝生物量实测数据,采用数理统计方法构建胡杨一级枝和树冠生物量估测模型,在精度检验基础上筛选出最佳模型,并对其估测值与实测值进行卡方检验。结果表明:使用以胡杨一级枝条的基部直径(D)和枝条长度(L)派生因子D2 L为自变量估测生物量(Sb)的模型Sb=125.546(D2 L)0.654最优,使用以冠幅面积(A)为自变量估测树冠生物量(Sc)的模型Sc=0.016A2+2.291A+11.084最优,在离河300m内,两模型平均估测精度分别为93.75%和87.01%;在离河600~1 500m进行估测时需根据修正因子进行修正,修正后平均估测精度分别为86.04%和84.32%。根据全收获法得到的胡杨树干平均材积密度(748.43kg.m-3)和样地每木检尺数据,使用树干材积计算式和树冠生物量估测模型,计算胡杨平均标准木的树干和树冠生物量,从而得到样地胡杨地上生物量数据。这一研究将为塔里木河流域胡杨生物量的遥感估测和胡杨林碳汇功能研究提供直接依据。 展开更多
关键词 生物量估测 胡杨(populus euphratica) 一级枝 树冠 塔里木河下游
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胡杨(Populus euphratica)种子萌发及胚生长对盐旱胁迫的响应 被引量:17
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作者 张肖 王旭 +1 位作者 焦培培 李志军 《中国沙漠》 CSCD 北大核心 2016年第6期1597-1605,共9页
测定了适宜温度和光照条件下胡杨(Populus euphratica)种子萌发及胚生长对盐胁迫和干旱胁迫的响应。结果表明:(1)胡杨种子萌发的最佳条件是25℃/30℃和12h光照/12h黑暗的温光组合。光照虽然影响胚根的生长、抑制胚轴的伸长,但有利... 测定了适宜温度和光照条件下胡杨(Populus euphratica)种子萌发及胚生长对盐胁迫和干旱胁迫的响应。结果表明:(1)胡杨种子萌发的最佳条件是25℃/30℃和12h光照/12h黑暗的温光组合。光照虽然影响胚根的生长、抑制胚轴的伸长,但有利于子叶长度的增加和子叶叶绿素的合成。低温(10℃/15℃、15℃/20℃)和高温(35℃/40℃)不利于胚根的伸长和子叶生长;黑暗条件下温度显著影响胚轴生长。(2)不同渗透势溶液对胡杨种子萌发后子叶的展开和胚根的生长影响较大。当溶液渗透势在-0.2-0 MPa时,胚的生长不受影响;而渗透势低于-0.2 MPa,下胚轴、胚根和子叶的生长都受到抑制,尤其当溶液渗透势低于-0.6 MPa时,子叶的展开也受到影响。-0.2 MPa是胡杨胚生长的一个临界渗透势。(3)胚根、子叶生长对NaCl胁迫比较敏感,表现为种子在0-0.80mol·L-1 NaCl溶液浓度范围内可以萌发,但胚根和子叶的生长在0.05mol·L-1浓度时与对照存在显著差异;在溶液浓度大于0.10mol·L-1时子叶出现黄化现象;而在0.20-0.80mol·L-1范围内子叶则不能正常展开。胡杨种子快速集中地萌发,是对干旱少雨环境的一种适应;而萌发后水、盐胁迫对胡杨胚生长的影响,是限制胡杨实生繁殖成功的关键。 展开更多
关键词 胡杨(populus euphratica) 种子萌发 胚生长 盐旱胁迫
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黑河下游不同生境胡杨(Populus euphratica)叶片碳同位素组成特征 被引量:15
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作者 袁亚鹏 赵阳 +1 位作者 赵传燕 李文娟 《中国沙漠》 CSCD 北大核心 2015年第6期1505-1511,共7页
植物中稳定碳同位素组成不但与植物的水分利用效率密切相关,而且反映环境因子对植物的影响。选择黑河下游额济纳旗为研究区,以优势物种胡杨(Populus euphratica)为研究对象,利用稳定碳同位素组成分析研究区胡杨受干旱胁迫程度。结果表明... 植物中稳定碳同位素组成不但与植物的水分利用效率密切相关,而且反映环境因子对植物的影响。选择黑河下游额济纳旗为研究区,以优势物种胡杨(Populus euphratica)为研究对象,利用稳定碳同位素组成分析研究区胡杨受干旱胁迫程度。结果表明:胡杨叶稳定碳同位素组成(δ13 C)处于-25.51‰^-30.21‰,平均值为-28.28‰。随干旱胁迫程度增加,δ13 C值有明显偏正趋势,植物(叶片)碳同位素组成对胡杨成熟木长期适应不同水分胁迫程度有明显的体现。分析δ13 C与胡杨生长状态发现,δ13 C与种群密度相关性不明显,与枯枝比呈显著正相关关系,枯枝比可成为碳同位素组成的替代指标,指示胡杨受干旱胁迫的程度。 展开更多
关键词 黑河 胡杨(populus euphratica) 稳定碳同位素组成 生长态势 枯枝比
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塔里木河上游胡杨(Populus euphratica、柽柳(Tamarix ramosissima)水分来源的稳定同位素示踪 被引量:22
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作者 周天河 赵成义 +3 位作者 吴桂林 蒋少伟 俞永祥 王丹丹 《中国沙漠》 CSCD 北大核心 2017年第1期124-131,共8页
通过分析塔里木河上游胡杨(Populus euphratica)、柽柳(Tamarix ramosissima)茎干水和各潜在水源(河水、土壤水、地下水)的δD、δ^(18)O同位素组成,应用多水源混合模型(IsoSource模型)研究了胡杨、柽柳的水分来源和对各潜在水源的利用... 通过分析塔里木河上游胡杨(Populus euphratica)、柽柳(Tamarix ramosissima)茎干水和各潜在水源(河水、土壤水、地下水)的δD、δ^(18)O同位素组成,应用多水源混合模型(IsoSource模型)研究了胡杨、柽柳的水分来源和对各潜在水源的利用比例。结果表明:0~100cm土壤水受蒸发影响大,土壤水δ^(18)O值偏大;100~300cm土壤水和地下水δ^(18)O值偏小且各点不存在显著差异。柽柳茎干水的δ^(18)O值小于胡杨,且均随河岸距离增加而减小;在河岸,胡杨最多能利用14.2%的河水,柽柳对河水的利用比例最大达到35.3%,二者对浅层0~100cm土壤水的利用比例较高;远离河岸,胡杨主要利用大于120cm的土壤水和地下水,对地下水的利用比例40%~50%,柽柳以地下水作为其主要水源,最大利用比例达到94.5%。胡杨生长需要适宜的地下水埋深条件(350~420cm),柽柳在浅地下水埋深和大于450cm的深地下水埋深条件下均能良好生长,对不同水分条件的适应能力优于胡杨。 展开更多
关键词 δD、δ18O稳定同位素 塔里木河 河岸带 胡杨(populus euphratica)、柽柳(Tamarix ramosissima) 水分来源
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