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1.
在福建闽侯县南屿林场的14~23年生发病的国外松种子园和试验林、用材林中,采用施肥防治、农药防治、综合防治等措施进行松枯梢病控制试验.结果表明:根施或叶面喷洒硼砂、根施或喷洒多菌灵、喷百菌清油烟利、燃放多菌灵等烟剂对松枯梢病有一定的防治效果;叶面喷施硼砂防效达67.5%,喷百菌清油烟剂的防效为69.7%,采用杀菌烟剂防效达66.1%;5种综合防治措施对松枯梢病有较好的控制作用,防治效果达69.5%~81.5%,尤其是采用清理病枯梢 根施硼肥 根施多菌灵的措施,防治效果达81.5%.  相似文献   

2.
落叶松枯梢病是我国北方落叶松人工林的主要病害,东北地区、华北、西北等省区均有发生,被害林木轻成造成枯梢,重者树冠变形甚至整株枯死。本文从枯梢病的发病规律和发病诱因等方面做了阐述,并提供了基本的防治方法。  相似文献   

3.
红栀子白纹羽病发生规律及综合防治   总被引:3,自引:0,他引:3  
通过对红栀子根部病害的调查、室内保湿培养、病原菌分离鉴定,结果表明:引起红栀子黄叶、枯梢甚至于死亡等明显症状的主要病原菌为白纹羽病菌(Ruselliniu necutrix褐座坚壳菌)。病害在低洼潮湿或排水不良的高温季节,5—8月蔓延很快,药剂防治试验以40%五氯硝基苯粉剂500倍、25%果病克星乳油800倍防治红栀子白纹羽根部病害90天后相对防治效果分别为77.6%和73.2%。  相似文献   

4.
黑龙江省是林业大省,特别是我们阿城区地类也较为复杂,东部属半山区,西部属平原区,由于落叶松适宜各类土壤生存,因此林农大多数造林都以落叶松为主,但是近几年来,落叶松枯梢病在本地区有零星发生,但不能轻视,近些年笔者通过实地观测密切进行研究和观察,总结出落叶松人工林枯梢病的防治技术,现总结如下。  相似文献   

5.
王翠伟 《科技资讯》2013,(29):147-147,149
对保护地葡萄病虫害进行调查,主要发生病害有霜霉病,白腐病,黑痘病,褐枯病,灰霉病,主要虫害有毛毯病,虎夜蛾,二星叶蝉,短须螨,蓟马,提出保护地葡萄病虫害的综合防治措施。  相似文献   

6.
本文概述了福建省仙游县桉树常见的青枯病和红叶枯梢病等主要病害的危害症状,并结合生产实践提出防治技术措施,为桉树持续健康经营提供参考。  相似文献   

7.
本文概述了福建省桉树常见的灰霉病、茎腐病、焦枯病、青枯病和红叶枯梢病等主要病害的危害症状,并结合生产实践提出防治技术措施,为桉树持续健康经营提供参考.  相似文献   

8.
樟子松枯死原因与防治技术研究   总被引:7,自引:0,他引:7  
根据生态环境学和现代森林病理学的原理与方法,通过多学科联合攻关,深入系统地研究了樟子松(Pinus sylvestris var.mongolica)枯死的难题,搞清了樟子松枯死的起因与机理.提出以营林措施为主的防治技术对策,为经营樟子松人工林、增强林分的生态功能提供了依据.该项研究丰富了森林病理学内客,补充了松枯梢病的研究成果,为林间生产应用提供了科学依据和技术方法。  相似文献   

9.
本文阐述用硼砂、硫酸锌、硫酸铜三种微量元素对巨尾桉红叶梢病防治,在巨尾桉树头旁挖穴深15cm,施单一硼砂或硼砂、硫酸锌、硫酸铜混合防治均有明显效果,最好的是硼砂12g﹢硫酸锌3g,其次是硼砂18g﹢硫酸锌3g﹢硫酸铜3g和硼砂18g﹢硫酸锌3g,因此建议可用硼砂﹢硫酸锌控制桉树红叶梢枯病危害。  相似文献   

10.
松梢枯病防治新技术及其机理研究   总被引:7,自引:0,他引:7  
水杨酸和多效唑预处理可以减轻湿地松梢枯病的发生、水杨酸的效果尤佳。病原孢子萌发试验证明,多效唑具有抑菌或杀菌作用,而水杨酸对病原孢子萌发及菌丝生长均无抑制作用。因此认为水杨酸处理后是通过增强湿地松的抗性来抑制梢枯病的发生。经水杨酸和多效唑处理后,嫩梢中超氧化物歧化酶(SOD)活性明显上升。SOD在湿地松抗梢枯病上可能起积极作用。较高浓度的水杨酸及阿斯匹林引起嫩梢苯丙氨酸解氨酶(PAL)活性下降。说  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
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   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
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   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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