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1.
分析了不同程度干旱周期性胁迫对广东乐昌、湖北远安、湖南汝城、浙江江山、安徽霍山5个种源马尾松苗木针叶内可溶性糖含量的影响。结果表明:干旱胁迫对不同种源马尾松苗木针叶内甘露糖、葡萄糖、半乳糖和麦芽糖的含量有显著影响。甘露糖在马尾松苗木针叶内的积累总体上随胁迫时间延长而增加,处理36 d后,对照平均上升37.75%,中度干旱胁迫下平均上升59.07%,重度干旱胁迫下平均上升60.95%;马尾松苗木针叶内葡萄糖含量在胁迫的前两个周期内变化规律性不强,但在3个周期的干旱胁迫后,可以明显地看出对照与处理间葡萄糖含量的差异;半乳糖含量在干旱胁迫的前期变化不稳定且种源间差异不显著,但随胁迫时间延长总体呈现稳定上升趋势;干旱胁迫下,各处理周期马尾松苗木针叶内麦芽糖含量变化不一,但总体表现下降趋势。总体上,可溶性糖组分在安徽霍山种源中积累较丰富,广东乐昌种源中次之,湖北远安、浙江江山、湖南汝城3种源中积累相对较少。  相似文献   

2.
通过对我国广泛分布的5种野生蔷薇资源(金樱子、毛萼蔷薇、长尖叶蔷薇、木香花、蛾眉蔷薇)的相对电导率、脯氨酸含量、可溶性蛋白含量、可溶性糖含量及丙二醛含量指标的测定,结合隶属函数法综合评价5个野生蔷薇种的抗寒性.结果表明:相对电导率、可溶性蛋白含量、可溶性糖含量及丙二醛含量均随温度降低而不断上升,脯氨酸含量则表现出降低→升高→降低的趋势.5种蔷薇属野生资源的抗寒性由强到弱依次为:峨眉蔷薇,木香花,长尖叶蔷薇,金樱子,毛萼蔷薇.  相似文献   

3.
在正常及低温胁迫条件下,对高粱3853—1与高粱3801—2苗期超氧化物歧化酶(SOD)、过氧化氢酶(CAT)及游离脯氨酸、可溶性糖、丙二醛(MDA)等指标进行了测定与分析,结果表明:在正常生长环境下,高粱3853—1的SOD与CAT的活性以及游离脯氨酸和可溶性糖的含量均大于高粱3801-2,MDA的含量低于高粱3801—2;在低温胁迫下,高粱3853—1与高粱3801—2叶片中MDA的含量增高.其余4项指标都比正常环境下低;高粱3853-1叶片中SOD与CAT的活性、可溶性糖及游离脯氨酸的含量均高于高粱3801—2;与高粱3801—2相比较,高粱3853—1有较强的抗性.  相似文献   

4.
福建柏抗寒生理指标变化研究   总被引:3,自引:0,他引:3  
对福建柏1-2年生苗木进行-8℃,-15℃低温胁迫处理试验测定表明,在处理24h情况下,植株体内内绿素和脯氨酸的含量比对照(自然低温-4℃)都有所升高,而根活力指标均有所降低;且种源间差异明显:叶绿素和脯氨酸含量的增加率为仙游和南靖种源均大于德化种源;根活力指标的降低率为仙游<南靖<德化。对仙游种源2年生苗木低温处理试验测定表明,叶绿素和脯氨酸含量在处理24h时均升高,但在处理48h、72h时叶绿素含量明显下降;脯氨酸含量在处理72h时明显升高。可溶性糖含量在处理48h和72h后有所升高。MDA含量在冷冻处理时均升高,田间同步观测表明,在-7℃ 24h自然低温条件下,2生福建柏苗仅出现少量侧枝顶端鳞叶轻微受冻;-8℃持续48h自然低温,则出现中度冻害(多数苗木未见顶梢受冻);而经-8℃处理72h,-15℃处理48h和72h的苗木绝大多数冻死。低温处理福建柏叶绿素、脯氨酸和根活力指标的变化是植株适应不利气温的生理机制调节反应。利用低温胁迫处理后上述生理指标的变化,可以寻求评估耐寒种源的途径,并为北移引种提供科学实验依据。  相似文献   

5.
仁用杏抗寒性生理指标评价的研究   总被引:3,自引:0,他引:3       下载免费PDF全文
对抗寒性不同的3个仁用杏品种(抗寒性强弱排序为优一>白玉扁>龙王帽)枝条低温处理后,检测其萌芽率和抗寒性生理指标,并对这些生理指标与抗寒性的关系作了研究。结果表明,随温度的降低,萌芽率降低,电解质渗出率、可溶性糖和脯氨酸的含量、SOD和POD的酶活性呈上升趋势;仁用杏品种间抗寒性差异显著性分析显示,枝条的电解质渗出率、表皮的可溶性糖和游离脯氨酸的含量、木质部和表皮的POD酶活性可以作为仁用杏抗寒性能力评价指标,SOD酶活性不宜作为抗寒性评价指标;主成分分析表明,采用这些生理指标对仁用杏抗寒性进行综合评价的结果是可靠的。  相似文献   

6.
5个常绿阔叶园林树种对低温变化的生理响应   总被引:3,自引:0,他引:3  
以南京地区引种的5个常绿阔叶园林树种为研究对象,探讨各树种叶片的膜透性、可溶性糖含量、POD酶活性、多胺含量等生理生化指标对低温变化的响应。结果表明:(1)在测定期内,除乐东拟单性木兰外,其余4个树种叶片的细胞膜透性均表现出先升高后降低再升高的变化趋势。浙江樟的质膜透性相对比较稳定,红花木莲变幅最大。(2)5个树种叶片可溶性糖含量,游离脯氨酸含量,叶片POD活性,腐胺(Put)、亚精胺(Spd)及精胺(Spm)含量与多胺总含量等均呈现先上升后下降趋势。(3)在最低气温到来前叶片可溶性糖含量调整到最大值;随低温时间延长和低温强度加剧各树种叶片中游离脯氨酸含量逐渐积累,变化幅度最大的是秃瓣杜英和乐东拟单性木兰;乐东拟单性木兰POD活性最大值出现较早且稳定,浙江樟POD活性较高且稳定,红花木莲与乐昌含笑的POD活性变化不稳定。(4)浙江樟和乐东拟单性木兰各月低温半致死温度(LT50)均较低。除浙江樟外,其他树种的LT50与采样前10天的日平均最低气温显著相关。(5)除乐昌含笑外,其他树种通过调节多胺含量适应外界低温变化。  相似文献   

7.
3种彩色树木抗寒生理指标测定与分析   总被引:3,自引:0,他引:3  
以"中华红叶杨"(Populus euramevicana cv.)、"金叶国槐"(Robinia pseudoacacia)、"中华金叶榆"(Ulmus pumila cv.jinye)的引种原生苗为试验材料,研究了人工模拟低温条件下,膜透性、可溶性糖、脯氨酸、超氧化物歧化酶、过氧化物酶等生理生化指标的变化规律。深入分析了生理指标与树种抗寒性的关系,通过隶属函数分析,确定各树种的抗寒性强弱。测定结果表明,三个彩色树种中金叶国槐抗寒性最弱。引种金叶国槐到西宁地区作为园林栽培树种,易受低温的危害。  相似文献   

8.
在旱作条件下对3个不同基因型水稻开花后8~40d剑叶叶绿素含量、可溶性糖含量、脯氨酸含量、MDA含量、SOD活性、POD活性等生理指标进行了测定分析。结果表明:不同基因型水稻开花后8~40d剑叶SOD活性和可溶性糖含量都呈明显下降趋势,脯氨酸含量和MDA含量则呈明显上升趋势;品种52-7剑叶SOD活性和脯氨酸含量始终保持较高水平,较适宜旱作。相关分析表明,SOD活性与MDA含量存在极显著线性负相关,SOD活性与可溶性糖含量存在极显著线性正相关;MDA含量与叶绿素含量、可溶性糖含量存在显著线性负相关,脯氨酸含量与可溶性糖含量存在极显著线性负相关。  相似文献   

9.
陈代慧  刘宇新  王艳梅  刘震 《河南科学》2013,(12):2154-2159
为了探索不同品种山茶花茶梅(Camelliasasanqua)、金花茶(Camellianitidissima)、七星球(Camelliaiaponica‘Sevenstar’)的抗寒性,采用人工模拟低温的方法对3年生的3个山茶花品种进行低温处理,系统测定叶片中超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量、游离脯氨酸、可溶性蛋白以及叶绿素含量指标的变化,分析各指标与抗寒能力的关系.结果表明:SOD活性在其低温耐受范围内,SOD活性升高的越快,抗寒性越强;抗寒性强的茶梅、七星球的MDA含量变化幅度较小,抗性弱的金花茶MDA含量变化幅度大;叶片中游离脯氨酸含量随低温胁迫程度的加深而升高,升高越剧烈抗寒性越弱;根据-5℃和-10oC可溶性蛋白含量变化可判断抗寒性强弱,正值较强负值较弱;叶绿素含量在0cc低温胁迫下含量随胁迫时间的延长而上升,抗寒性强的在-5℃、-10℃低温胁迫下呈上升一下降趋势,而抗性弱的随低温胁迫程度的加深含量下降.各指标在低温逆境胁迫下相互协调,共同发生作用.  相似文献   

10.
甘蔗品种抗旱力与生理指标的关系   总被引:2,自引:0,他引:2  
测定了四个甘蔗品种的茎伤流量、叶片游离脯氨酸、可溶性糖和叶绿素的含量四项生理指标。结果表明:品种间伤流量差异显著;正常供水植株品种间游离脯氨酸含量、可溶性糖含量和叶绿素含量差异不显著,而受旱后品种间上述三项指标差异(极)显著。从四项指标来判断,粤糖71-210和粤糖63-237是较耐旱品种,而粤糖57-423是较不耐旱品种。甘蔗抗旱力与四项生理指标密切相关。  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

15.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

16.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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