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根据美洲黑杨PdZFR部分cDNA序列,采用拟基因组文库步行法和RACE克隆了该基因全长cDNA及基因组DNA, 并对该基因的启动子、转录起始位点、内含子分布、剪切方式、编码的氨基酸序列和该基因在染色体上的分布位置进行了分析。组织或器官特异表达分析表明:该基因与植物发育相关。  相似文献   

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马来西亚优良油棕品种的引种与栽培   总被引:1,自引:0,他引:1  
油棕是热带著名的油料作物,是一种重要的食用油和生物柴油资源,在中国热区颇具发展前景。笔者从马来西亚引进优良油棕品种,在西双版纳进行育苗和试种,结果表明:优良油棕品种在中国热区能正常生长发育,3年生植株高4.22 m,地径0.45 m,定植后第4年开花,花穗饱满,生长良好,引种已基本成功。文章还介绍了油棕的育苗和造林技术,为中国热区油棕产业发展奠定技术基础。  相似文献   

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马来西亚优良油棕品种的引种与栽培技术   总被引:2,自引:0,他引:2  
油棕是热带著名的油料作物,是一种重要的食用油和生物柴油资源,在中国热区颇具发展前景。笔者从马来西亚引进优良油棕品种,在西双版纳进行育苗和试种,结果表明:优良油棕品种在中国热区能正常生长发育,3年生植株高4.22m,地径0.45m,定植后第4年开花,花穗饱满,生长良好,引种已基本成功。文章还介绍了油棕的育苗和造林技术,为中国热区油棕产业发展奠定技术基础。  相似文献   

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沙冬青(Ammopiptanthus mongolicus.(Maxim)Cheng.f)为我国西北荒漠区唯一的常绿灌木,具有极强的抗性。本文对低温、干旱和盐胁迫下沙冬青幼苗中脯氨酸积累的变化进行研究,以期探讨不同胁迫下脯氨酸累积的共性和特异性,为进一步探讨逆境下脯氨酸积累的生理意义提供参考。  相似文献   

6.
The 9-cis-epoxycarotenoid dioxygenase(NCED)gene is rate-limiting in abscisic acid(ABA) biosynthesis.In this study, an NCED gene, designated FvNCED3(KY008746), was cloned from velvet ash(Fraxinus velutina Torr.) with a RACE method. The full length c DNA of FvNCED3 encodes a 573-amino acid polypeptide.Sequencing analysis showed that the FvNCED3 protein was highly homologous to other NCED proteins. The expression patterns of FvNCED3 in different ash organs were analyzed by real-time PCR which revealed that FvNCED3 expression levels were highest in leaves and lowest in roots. The gene expression patterns of FvNCED3 under abiotic stress indicated that its expression increased under drought, salt and ABA stress and decreased due to high and low temperatures. There were no obvious changes under ultraviolet light. The 1094-bp upstream sequence 5' flank regulation region of the FvNCED3 gene was also cloned from ash using the Genome Walking method. To assess the activity of the FvNCED3 promoter, a p FvNCED3 p::GUS plant expression vector was constructed for tobacco transformation. GUS expression of the FvNCED3 GUS enzyme activity was detected in almost all transgenic tobacco tissues, especially in the young leaves,stigma, anther, ovule and ovary. After treating the transgenic tobacco with NaCl and placing it under drought stress, GUS staining of tobacco leaves increased compared with that under normal growth conditions. This result indicates that gene expression driven by the FvNCED3 promoter can be induced by salt and drought stress.  相似文献   

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以水稻品种日本晴DNA为模板,用PCR的方法从水稻胚特异性表达基因OsESG上游序列扩增出特异性条带,克隆出种子胚特异性启动子,长度为1.1kb,且已知的功能部位序列没有发生改变。用它构建了带动报告基因GUS表达的双元载体,并用农杆菌介导法转化水稻得到了转基因植株。对GUS基因的表达检测表明,由该启动子序列引导的GUS基因仅在胚中特异性表达,而其它组织中都未表达,证实该启动子具有胚特异性表达的功能。  相似文献   

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刚毛柽柳NAC24基因的表达及抗逆功能分析   总被引:2,自引:0,他引:2  
【目的】NAC类转录因子是植物特有的最大的转录因子家族之一,广泛参与植物的生长发育过程,并在植物响应盐、干旱等多种非生物胁迫的过程中发挥至关重要的调控作用。本研究拟从盐生木本植物刚毛柽柳中克隆获得一个NAC转录因子基因,研究该基因的耐盐、抗旱功能,以期为研究木本植物NAC转录因子的抗逆分子机制奠定理论基础。【方法】在刚毛柽柳NaHCO_3胁迫转录组数据库中筛选获得一个NAC转录因子基因,将其命名为ThNAC24(GenBank登陆号:KF031949)。利用生物信息学工具将其与其他9个物种的NAC蛋白进行多序列比对,与拟南芥105个NAC蛋白进行进化树分析。分别用300 mmol·L-1 NaCl和400 mmol·L-1甘露醇对刚毛柽柳进行胁迫,在胁迫6、12、24和48 h后分别取刚毛柽柳根及叶组织。通过实时荧光定量RT-PCR(qRT-PCR)技术分析盐、干旱胁迫下ThNAC24基因在不同胁迫时间点及不同组织的表达情况,初步鉴定其是否响应盐、干旱胁迫。为进一步研究ThNAC24基因的抗逆功能,分别构建植物过表达(pROKⅡ-ThNAC24)及抑制表达(pFGC5941-ThNAC24)载体。利用农杆菌介导的高效瞬时遗传转化体系获得ThNAC24基因瞬时过表达(OE)、抑制表达(IE)及对照(Control)刚毛柽柳植株。在盐、干旱胁迫下分析比较了ThNAC24基因瞬时过表达、抑制表达及对照刚毛柽柳植株的二氨基联苯胺(DAB)和氯化硝基四氮唑蓝(NBT)染色情况,过氧化物酶(POD)和超氧化物歧化酶(SOD)活性,及电解质渗透率、失水率及丙二醛(MDA)含量,鉴定ThNAC24基因的耐盐、抗旱功能。【结果】ThNAC24基因的开放阅读框为1 023 bp,编码340个氨基酸。多序列比对结果显示ThNAC24在N端的氨基酸序列相似度比较高,具有NAC家族的序列特征;系统进化树分析结果显示ThNAC24与ANAC103和ANAC082的亲缘关系较近。qRT-PCR结果显示:盐胁迫下,ThNAC24基因上调表达,在根组织中胁迫12 h表达量最高,而叶组织中胁迫24 h的表达量最高;干旱胁迫下,ThNAC24基因上调表达,在根组织中胁迫6 h表达量最高,在叶组织中胁迫12 h的表达量最高。ThNAC24基因在刚毛柽柳根和叶组织中均有表达且响应盐和干旱胁迫。过表达ThNAC24基因显著降低了刚毛柽柳H_2O_2和超氧阴离子含量,增强了POD和SOD酶的活性,从而减少活性氧(ROS)的积累。过表达ThNAC24基因能够降低刚毛柽柳在逆境胁迫下的电解质渗透率、失水率及MDA的积累,从而保护细胞膜结构的完整性。【结论】刚毛柽柳ThNAC24基因能够响应盐、干旱胁迫,过表达ThNAC24基因植株通过增强POD和SOD活性,进而提高ROS清除能力,减少细胞受损或死亡,从而提高刚毛柽柳的耐盐及抗旱能力。  相似文献   

10.
Binderless boards were prepared from steam-exploded fiber of oil palm(Elaeis guineensis Jacq.) frond at six levels of explosion conditions. Their properties were investigated and evaluated. The mechanical properties (i.e., modulus of rupture, modulus of elasticity, and internal bonding strength) of the boards increased linearly with increasing board density as the usual hardboard. The boards made from fibers treated under a steam explosion condition of 25 kgf/cm2 (steam pressure) and 5 min (digestion period) exhibited the maximum strength. These boards at a density of 1.2 g/cm3 met the requirement of S-20 grade of JIS A 5905 — 1994 (fiberboard). Thickness swelling of the boards ranged from 6% to 14% under the JIS A 5908 — 1994 (particleboard) test condition and showed no significant changes with increasing board density. The main bonding strength of the board is believed to be due to a ligninfurfural linkage. Considering the chemical components of oil palm frond, which is rich in hemicellulose, there seems to be a good possibility for producing binderless boards using steam-exploded fibers of oil palm frond.This study was presented in part at the 2nd International Wood Science Seminar, Serpong, Indonesia, November 1998  相似文献   

11.
Many products and abundant wastes from tropical plantations, such as latex, palm oil, and coconut production due to replantation, are waiting effective utilization. Nonutilized tropical biomass — oil palm (Elaeis guneensis Jacq.), coconut (Cocos nucifera L.) coir dust and coir fiber, and rubber (Hevea brasiliensis) wood — were analyzed for chemical and structural characteristics of wall polysaccharides and lignin. Coconut coir dust is mostly composed of middle lamella and is separated from coir fiber, which is composed of secondary walls. These were supported by lignin content, and structural characteristics of wall polysaccharides and lignin. The chemical and spectroscopic characteristics of walls of rubber xylem were similar to those of typical temperate angiosperm woods. Oil palm frond was significantly rich in arabinoxylan, and numerous acetyl groups were substituted to the arabinoxylan. Lignin of oil palm frond and wall polysaccharides of coconut coir dust are substituted with hydroxybenzoic acids with ester and ether linkages. Some p-hydroxybenzoic acid substituted to the wall polymers of coconut coir dust would contribute to the formation of associations between polysaccharides and lignin. Based on the above results it is suggested that coconut coir fiber and rubber wood are suitable resources for chemical pulp production for paper-making, but oil palm frond is not.  相似文献   

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The role of late embryogenesis abundant (LEA) proteins in stress tolerance was examined by using a yeast expression system. LEA protein tolerance to the abotic stresses in plants involved in salt, drought and freezing stresses and additional tolerance to heat, NaHCO3 (salt-alkali) and ultraviolet radiation was also investigated. The transgenic yeast harboring the Tamarix LEA gene (DQ663481) was generated under the control of inducible GAL promoter (pYES2 vector), yeast cells transformed with pYES2 empty vector were also generated as a control. Stress tolerance tests showed that LEA yeast transformants exhibited a higher survival rates than the control transformants under high temperature, NaHCO3, ultraviolet radiation, salt (NaCl), drought and freezing, indicating that the LEA gene is tolerant to these abiotic stresses. These results suggest that the LEA gene is resistant to a wider repertoire of stresses and may play a common role in plant acclimation to the examined stress conditions.  相似文献   

13.
The aim of this work was to investigate the structure–property relationships of two different monocotyledon trunks: bamboo (Bambusa blumeana Schultes) and oil palm (Elaeis guineensis Jacq). Anatomical characteristics (fraction of fibers) and physical (density, water uptake, and swelling in the radial direction) and mechanical (modulus of rupture and modulus of elasticity) properties of bamboo and oil palm trunks were examined. The results showed that the examined properties of both species were mainly governed by fibers. Those of bamboo were mostly greater. Functions relating most of the examined properties to the density of both species were finally achieved. Based on the results obtained, it is suggested that bamboo has a higher potential for structural application, while oil palm wood is more likely to be utilized for non-structural purposes.  相似文献   

14.
African oil palm (Elaeis guineensis Jacq.) is considered the most productive oleaginous crop due to its high oil production per hectare. In April 2015, E. guineensis leaves showing elliptical necrotic spots with yellowish halo were observed in a commercial plantation in Moju, Pará state, Brazil. A synematous fungus was consistently observed associated with the necrotic spots. The aim of this study was to identify this fungus associated with E. guineensis in Brazil. Based on morphology and DNA sequence data of the internal transcribed spacer rDNA, the fungus was identified as Helminthosporiella stilbacea. Helmintosporiella stilbacea has been reported associated with leaf spots on E. guineensis in Africa, Ghana, Sudan and Zambia. To the best of our knowledge, this is the first report of H. stilbacea associated with E. guineensis in Brazil.  相似文献   

15.
In order to investigate the potential for efficient utilization of oil palm (Elaeis guineensis), supercritical water treatment (at 380°C and 100 MPa for 8 s) was applied to fractionate extractives-free samples into water-soluble portion and water-insoluble portion. The water-insoluble portion was further fractionated into methanol-soluble portion and methanol-insoluble residue. Samples were prepared from various parts of oil palm, i.e., trunks, fronds, mesocarp fibers, shells, empty fruit bunches, and kernel cake. These fractionated products were then characterized analytically. The water-soluble and methanol-soluble portions were determined to be mainly composed of carbohydrate-derived products and lignin-derived products, respectively. The methanol-insoluble residue was mainly composed of lignin (more than 84 wt%) and the phenolic hydroxyl contents determined by the aminolysis method was higher than for untreated oil palm samples. In addition, an alkaline nitrobenzene oxidation analysis indicated that the methanol-insoluble residue contained fewer oxidation products than untreated samples did. These findings imply that the water-soluble portion could be utilized for organic acid production, whereas the methanol-soluble portion and the insoluble residue could be used for the production of phenolic chemicals.  相似文献   

16.
碳酸盐和干旱胁迫对欧李生理特性的影响   总被引:6,自引:0,他引:6  
分别对黄山店欧李进行25 d的高浓度NaHC03溶液处理、干旱处理以及碳酸盐与干旱共同处理,测定胁迫期间该物种各理化指标的变化,研究欧李对不同环境胁迫的抗逆机制.结果表明:欧李的叶绿素a、丙二醛和脯氨酸含量在不同的逆境处理间差异显著;碳酸盐处理的电解质外渗率、POD活性、脯氨酸含量等生理指标变化平缓,与对照差异不明显;干旱处理和盐与干旱协同处理的各项指标波动很大.相关分析表明:不论是碳酸盐胁迫还是干旱胁迫,欧李的电解质外渗率、MDA含量和POD活性存在一定程度的正相关,碳酸盐处理下POD活性与电解质外渗率和MDA含量间达到显著的正相关.  相似文献   

17.
Li M  Li Y  Li H  Wu G 《Tree physiology》2011,31(3):349-357
Paper mulberry (Broussonetia papyrifera L. Vent) is well known for its bark fibers, which are used for making paper, cloth, rope, etc. It was found that, in addition to its well-documented role in the enhancement of plant salt tolerance, overexpression of the Na+/H+ antiporter (AtNHX5) gene in paper mulberry plants showed high drought tolerance. After exposure to water deficiency and salt stress, the wild-type (WT) plants all died, while the AtNHX5-overexpressing plants remained alive under high salt stress, and had a higher survival rate (>66%) under drought stress. Measurements of ion levels indicated that Na+ and K+ contents were all higher in AtNHX5-overexpressing leaves than in WT leaves in high saline conditions. The AtNHX5 plants had higher leaf water content and leaf chlorophyll contents, accumulated more proline and soluble sugars, and had less membrane damage than the WT plants under water deficiency and high saline conditions. Taken together, the results indicate that the AtNHX5 gene could enhance the tolerance of paper mulberry plants to multiple environmental stresses by promoting the accumulation of more effective osmolytes (ions, soluble sugars, proline) to counter the osmotic stress caused by abiotic factors.  相似文献   

18.
Felled palm trunks are susceptible to fungi as long as their moisture content is above fibre saturation. During this period, palm wood has to be protected against mould and rot fungi. The study was aimed at testing environment-friendly organic acids for their protecting efficiency. Small samples of date palm (Phoenix dactylifera) and oil palm (Elaeis guineensis) wood were treated with weak organic acids and subsequently infected by moulds and wood-decay fungi. Short dipping of the samples in solutions of 5% acetic acid and propionic acid, respectively, protected all samples for two months from colonization by Aspergillus niger, Penicillium sp., Cladosporium sp. and by a natural infection. Boric acid (4%) used in practice for protection was ineffective. Decay tests with the white-rot fungus Pleurotus ostreatus, the brown-rot species Coniophora puteana and the soft-rot fungus Chaetomium globosum showed that both acids prevented most samples from fungal colonization for three weeks and reduced the decay considerably during two months.  相似文献   

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The current expansion of the oil palm (Elaeis guineensis Jacq.) in the Brazilian Amazon has mainly occurred within smallholder agricultural and degraded areas. Under the social and environmental scenarios associated with these areas, oil palm-based agroforestry systems represent a potentially sustainable method of expanding the crop. The capacity of such systems to store carbon (C) in the soil is an important ecosystem service that is currently not well understood. Here, we quantified the spatial variation of soil C stocks in young (2.5-year-old) oil palm-based agroforestry systems with contrasting species diversity (high vs. low); both systems were compared with a ~10-year-old forest regrowth site and a 9-year-old traditional agroforestry system. The oil palm-based agroforestry system consisted of series of double rows of oil palm and strips of various herbaceous, shrub, and tree species. The mean (±standard error) soil C stocks at 0–50 cm depth were significantly higher in the low (91.8 ± 3.1 Mg C ha?1) and high (87.6 ± 3.3 Mg C ha?1) species diversity oil palm-based agroforestry systems than in the forest regrowth (71.0 ± 2.4 Mg C ha?1) and traditional agroforestry (68.4 ± 4.9 Mg C ha?1) sites. In general, no clear spatial pattern of soil C stocks could be identified in the oil palm-based agroforestry systems. The significant difference in soil carbon between the oil palm area (under oil palm: 12.7 ± 2.3 Mg C ha?1 and between oil palm: 10.6 ± 0.5 Mg C ha?1) and the strip area (17.0 ± 1.4 Mg C ha?1) at 0–5 cm depth very likely reflects the high input of organic fertilizer in the strip area of the high species diversity oil palm-based agroforestry system treatment. Overall, our results indicate a high level of early net accumulation of soil C in the oil palm-based agroforestry systems (6.6–8.3 Mg C ha?1 year?1) that likely reflects the combination of fire-free land preparation, organic fertilization, and the input of plant residues from pruning and weeding.  相似文献   

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