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Microcycle Conidiation in Aciculosporium take,the Causal Agent of Witches' broom of Bamboo

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Microcycle Conidiation in Aciculosporium take,the Causal Age...

第三届中国森林保护学术大会

作者： Yang Yonggang Wu Xiaoqin~* Ye Jianren (College of Forest Resources and Environment Nanjing forestry University,The Key Laboratory of the pest preventioh and control of the Jiangsu Province,Nanjing 210037,china)

Witches’broom of bamboo caused by Aciculosporium take has become one of the destructive diseases for bamboo forests in *** conidia of *** are mainly transmitted by ***, their development which is important for understanding the disease epidemiology is not very *** our research,witches’ broom-diseased bamboo,Phyllostachys bambusoides ***(Marliac ex Carriere) Makino,was used as the source of conidia to exam the germination and cultural characters of A. *** observation and image acquisition were made by using LEICA DMLB2 microscope with LEICA DFC320 *** observation revealed that naturally formed 3-celled conidia germinated their end cells to produce a kind of cultural type conidia with curled dichotomously branched appendages at the *** the newly formed secondary spores fell off,3-celled conidia repeated the above process continually without formation of *** was no morphological change being observed in middle cell during the process of *** appendaged secondary spore directly formed from the conidia germination underwent the process of microcycle conidiation(MC) by sprouting a germ tube at its basal *** germ tube developed to a secondary spore finally and then fell off to become a brand new microcyclic structure while the mother spore repeated such process *** this way,the secondary spores formed from 3-celled conidia and then proliferated themselves without production of mycelium,and all these procedures were confirmed to have no apparent relationship with temperature and *** colony of *** grew extremely slowly on PDA medium and the development of its morphology appeared closely related to the process of *** first,the colony was milky white with sharp edge and the surface was strongly wrinkled as brain *** observation showed that the wrinkled colony was consisted of appendaged secondary spores *** 30 days later,white mycelia formed on

关键词： witches’ broom of bamboo Aciculosporium take conidia germination microcycle conidiation colony morphology

Study on endophytic Bacterium in Bursaphelenchus xylophilus,a cause of Pine wilt disease

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Study on endophytic Bacterium in Bursaphelenchus xylophilus,...

第三届全国生物入侵大会

作者： Wei-min Yuan,Xiao-qin Wu~*,Jian-ren Ye,Xiao-jing Tian Nanjing forestry University,the Key Laboratory of the Pest Prevention and control of the Jiangsu Province,Nanjing 210037,china

Pine wood nematode disease is a disastrous disease for *** relationship between Bursaphelenchus xylophilus and accompanying bacteria is concerned in recent *** no study was undertaken to cover endophytic bacteria in *** from different geographical areas and hosts were chosen to research on whether endophytic bacteria is present in nematodes and the relationship between endophytic bacteria and the pathogenic of different populations of ***. The body of nematodes soaked in 1%mercuric chloride and antibiotic mixture for surface sterilization is grinded and cultured by NA *** the basis

关键词： Bursaphelenchus xylophilus Endophytic bacteria Pathogenic Stenotrophomonas maltophilia Achromobacter xylosoxidans subsp Xylosoxidans

Measurement Models of Forest Biodiversity Variation and Its controlling Study in china

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Chinese forestry science and Technology 2003年第3期2卷 46-53页

作者： ZHANG YingCollege of Economics and Management, Beijing forestry University Beijing 100083. P. R. china

According to the evaluative data of forest biodiversity variation in china from 1973 to 1998, not only the gray model GM( 1,2), but also the status spatial characterization model with the optimal control model for forest biodiversity variation is developed by using some mathematic approaches and knowledge in economic cybernetics. Furthermore, the structural characteristics of forest biodiversity variation are analyzed. The paper points out that the variation of forest biodiversity is instable, but it ca...

关键词： forest biodiversity status analysis construction characteristics optimal control china

Synchronization of Chaotic Systems via Sliding Mode control with Fractional Approach Law

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Synchronization of Chaotic Systems via Sliding Mode Control ...

2011 Chinese control and Decision Conference（CCDC）

作者： Ning CHEN is with Nanjing forestry University,Nanjing,210037,china.Naizhou WANG.was with Nanjing forestry University,Nanjing,210037,china.He is now with the Department of automatic,South china University of Thchnology,Guangzhou,510741,china.

Based on the theory of fractional order differential equation,a fractional order control law for Sliding Mode control （SMC） is proposed in this *** a sliding mode controller is designed to synchronize the chaos motions between a slave Duffing system and a master Duffing system including a fractional integral ***,Chaos synchronization in the two systems is investigated and the numerical results confirm the validity of the proposed control strategy.

关键词： chaos synchronization Duffing system fractional calculus sliding mode control

Carbon dioxide exchange and the mechanism of environmental control in a farmland ecosystem in North china Plain

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science china Earth sciences 2006年第S2期49卷 226-240页

作者： LI Jun, YU Qiang, SUN Xiaomin, TONG Xiaojuan, REN Chuanyou, WANG Jing, LIU Enmin, ZHU Zhilin & YU Guirui institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china Graduate University of the Chinese Academy of sciences, Beijing 100049, china College of Resources and Environmental studies, Beijing forestry University, Beijing 100083, china 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 2. Graduate University of the Chinese Academy of sciences Beijing 100049 China 3. College of Resources and Environmental studies Beijing Forestry University Beijing 100083 China

CO2 flux was measured continuously in a wheat and maize rotation system of North china Plain using the eddy covariance technique to study the characteristic of CO2 exchange and its response to key environmental factors. The results show that nighttime net ecosystem exchange (NEE) varied exponentially with soil temperature. The temperature sensitivities of the ecosystem (Q10) were 2.94 and 2.49 in years 2002-2003 and 2003-2004, respectively. The response of gross primary productivity (GPP) to photosynthetically active radiation (PAR) in the crop field can be expressed by a rectangular hyperbolic function. Average Amax andαfor maize were more than those for wheat. The values ofαincreased positively with leaf area index (LAI) of wheat. Diurnal variations of NEE were significant from March to May and from July to September, but not remarkable in other months. NEE, GPP and ecosystem respiration (Rec) showed significantly seasonal variations in the crop field. The highest mean daily CO2 uptake rate was -10.20 and -12.50 gC·m-2·d-1 in 2003 and 2004, for the maize field, respectively, and -8.19 and -9.50 gC·m-2·d-1 in 2003 and 2004 for the wheat field, respectively. The maximal CO2 uptake appeared in April or May for wheat and mid-August for maize. During the main growing seasons of winter wheat and summer maize, NEE was controlled by GPP which was chiefly influenced by PAR and LAI. Rec reached its annual maximum in July when Rec and GPP contributed to NEE equally. NEE was dominated by Rec in other months and temperature became a key factor controlling NEE. Total NEE for the wheat field was -77.6 and -152.2 gC·m-2·a-1 in years 2002-2003 and 2003-2004, respectively, and -120.1 and -165.6 gC·m-2·a-1 in 2003 and 2004 for the maize field, respectively. The cropland of North china Plain was a carbon sink, with annual -197.6 and -317.9 gC·m-2·a-1 in years 2002-2003 and 2003-2004, respectively. After considering the carbon in grains, the cropland became a carbon source, which was

关键词： net ecosystem exchange gross primary productivity ecosystem respiration carbon budget eddy covariance winter wheat summer maize.

Edge Detection of Plant Roots Image via Gabor Wavelet Theory

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Edge Detection of Plant Roots Image via Gabor Wavelet Theory

2011 Chinese control and Decision Conference（CCDC）

作者： Wen-long Song is with the Department of Electromechanics Engineering,Northeast forestry University,Harbin 150040,china. Li-hui Wang is with the Department of Electromechanics Engineering,Northeast forestry University,Harbin 150040,china.Liang-kuan Zhu is with the Department of Electromechanics Engineering,Northeast forestry University,Harbin 150040,china.Fa-yi Qu is with the Department of Electromechanics Engineering,Northeast forestry University,Harbin 150040,china.

The pictures extracted from the plant roots often have quite big noises and often affected greatly by the light intensity,neither could we achieve satisfactory results by using the traditional image edge detection method to detect the edge *** this issue,a method for edge detection and its application in edge image detection for plant roots via gabor wavelet theory is proposed,which is able to filter from different directions and scales to determine the edge of the texture under perfect frequency,and proposes methods that using Gabor wavelet theory to detect the image edges of the plant *** results show that compared with other traditional edge detection methods,the proposed approach is effective in reduction of color space dimensionality and robust to noise.

关键词： Plant Roots Edge Detection Gabor wavelet theory Image Processing

Nutrient Management for Eucalypt Plantations in South china

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Chinese forestry science and Technology 2002年第1期1卷 33-45页

作者： KU Daping Bernie DELL1. Research institute of Tropical forestry, CAF, Guangzhou 510520, china 2. Murdoch University. Perth. Australia (dell@central.murdoch.edu.au)

Eucalypts are very popular for revegetation in many parts of south china because of their capacity to tolerate degraded sites and unfertile soils,and their fast growth potential to coppice. This paper reviews a decade of field trials in china, undertaken as part of several bilateral researchprograms in plantation forestry, concerning the use of fertilizers, harvest residue management and inoculation with ectomycorrhizal fungi. One of the key questions addressed is whether the productivity of plantation ...

关键词： afforestation sustainable forestry nutrient management mycorrhizal fungi

Economic Analysis of the Pollution Permits Trading Policy in Taihu Lake Basin

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Economic Analysis of the Pollution Permits Trading Policy in...

The 3rd International Conference on Environmental Technology and Knowledge Transfer

作者： SHEN Wenxing REN Hanzi (Department of Economics and Management Nanjing forestry University Nanjing 210037 china)

Aiming at the environmental pollution in Taihu Lake basin,this paper used relevant economic theories to explore the economic causes of the environmental ***,how to control the pollution and adopt positive and incentive-based policies,the pollution permits trading policy is very *** economic measures on the initial allocation of pollution permits,establishment of the trading platform,setting up of the coordination organizations and gradual reduction of the license were proposed.

关键词： Taihui Lake basin pollution permits trade

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水热控制下杨木的表层密实化及固定技术

木材工业 2012年第2期26卷 18-21页

作者：王艳伟黄荣凤张耀明中国林科院木材工业研究所国家林业局木材科学与技术重点实验室北京100091

通过改变木材的表层水分含量,并利用热压机压板的热量对木材进行水热控制,开展毛白杨木材的表层密实化研究,分析毛白杨木材表层压缩密实化后的密度、硬度和恢复率等能指标。结果表明:表层密实化后的毛白杨木材的表层密度达到0.92g/cm3,... 详细信息

通过改变木材的表层水分含量,并利用热压机压板的热量对木材进行水热控制,开展毛白杨木材的表层密实化研究,分析毛白杨木材表层压缩密实化后的密度、硬度和恢复率等能指标。结果表明:表层密实化后的毛白杨木材的表层密度达到0.92g/cm3,为对照材的1.8～2.1倍;硬度达到22.3N/mm2,为对照材的2.4倍;压缩木经180℃、4h的热处理后,变形恢复率可降低30%。

关键词：毛白杨水热控制表层密实化密度硬度固定