近年來(lái)隨著馬鈴薯產(chǎn)業(yè)的迅猛發(fā)展,我國(guó)馬鈴薯主產(chǎn)區(qū)土傳病害日趨加重,尤其是由立枯絲核菌（Rhizoctonia solani）侵染引起的馬鈴薯莖潰瘍�。ㄒ卜Q馬鈴薯立枯病,Potato Rhizoctonia canker,黑痣病,black scurf）已成為影響馬鈴薯產(chǎn)業(yè)發(fā)展的限制因子,不僅嚴(yán)重影響馬鈴薯塊莖的產(chǎn)量和品質(zhì),降低其商品性和貯藏性,也給種植戶造成了巨大的經(jīng)濟(jì)損失。立枯絲核菌對(duì)馬鈴薯植株的致病機(jī)理十分復(fù)雜,產(chǎn)生的毒素可能是其致病的關(guān)鍵因子,探明立枯絲核菌毒素在植株發(fā)病過(guò)程中的作用,對(duì)防治馬鈴薯黑痣病具有重要意義。本研究擬采用高效液相色譜（HPLC）、薄層色譜（TLC）、柱層析、紅外光譜（FTIR）、質(zhì)譜和核磁（NMR）分析等手段分離和鑒定病原菌毒素的活性成分,同時(shí)用毒素處理馬鈴薯莖基部,綜合采用植物病理學(xué)、生理學(xué)和細(xì)胞生物學(xué)等多學(xué)科的方法,揭示病原菌毒素對(duì)馬鈴薯莖潰瘍的致病機(jī)理,為更有效地防治馬鈴薯莖潰瘍病提供理論依據(jù)。主要試驗(yàn)結(jié)果如下:1.立枯絲核菌AG-3毒素的分離和鑒定（1）將分離到的38個(gè)樣品進(jìn)行TLC分析,在254nm紫外光下可以看見(jiàn)清晰的斑點(diǎn),制備TLC的最佳展開(kāi)... 

【文章來(lái)源】：甘肅農(nóng)業(yè)大學(xué)甘肅省

【文章頁(yè)數(shù)】：116 頁(yè)

【學(xué)位級(jí)別】：博士

【文章目錄】：
摘要
Summary
Abbreviations
Chapter 1 Introduction
    1.1 Economic importance of potato
    1.2 Phytopathogenic fungi attacking potato
    1.3 Rhizoctonia diseases of potato
        1.3.1 Rhizoctonia disease cycle and disease symptoms
        1.3.2 Anastomosis groups of R. solani
        1.3.3 Epidemiology of R. solani
    1.4 The management of Rhizoctonia potato disease
        1.4.1 Biocontrol
        1.4.2 Cultural practices
        1.4.3 Chemical control
        1.4.4 Preformed defense systems
        1.4.5 Organic matter amendments
    1.5 Fungal phytotoxins
        1.5.1 Definitions and chemical structures
        1.5.2 Phytotoxins from Rhizoctonia solani
    1.6 Objectives and significance of the study
Chapter 2 Isolation, purification and characterization of phytotoxins produced byRhizoctonia solani AG-3, the caused agent of potato stem canker
    2.1 Introduction
    2.2 Materials and methods
        2.2.1 Collection of sample
        2.2.2 Maintenance and storage of fungal cultures
        2.2.3 Culture media
        2.2.4 Isolation and identification of fungal pathogens
        2.2.5 Fungal cultures and toxin production
        2.2.6 Biological activity and stem canker assay
        2.2.7 Bioactivity of soluble macromolecular compounds obtained from culturefiltrates
        2.2.8 Solvent extraction
        2.2.9 Isolation and purification of the phytotoxins from culture filtrates
        2.2.10 Characterization of purified compound
        2.2.11 Potato stem canker response to MTPA and MTAA
        2.2.12 Statistical analysis
    2.3 Results
        2.3.1 Isolation and identification of fungi isolates
        2.3.2 Preliminary in vitro characterization
        2.3.3 Isolation and purification of R. solani toxin
        2.3.4 Potato stem canker response to toxin fractions
        2.3.5 IR spectra of the purified compounds
        2.3.6 HPLC of the purified compounds
        2.3.7 NMR spectra of the purified compounds
        2.3.8 Potato stem canker response to MTPA and MTAA
    2.4 Discussion
Chapter 3 Investigation of 3-methylthiopropionic acid of Rhizoctonia solani AG-3 and itsrole in the pathogenicity of the fungus
    3.1 Introduction
    3.2 Materials and methods
        3.2.1 Soil sterilization, source of seed and MTPA
        3.2.2 Potato stems canker response to MTPA
        3.2.3 Rhizoctonia growth response to MTPA
        3.2.4 Fungal culture filtrates and toxin production
        3.2.5 Bioassay for phytotoxicity
        3.2.6 Influence of pH on toxin activity
        3.2.7 Experimental design
        3.2.8 Data collection
        3.2.9 Statistical analyses
    3.3 Results
        3.3.1 The effect of pH on phytotoxin activity
        3.3.2 Plant height, stem diameter, number of stolon and symptomless stolon
        3.3.3 Canopy development
        3.3.4 Effect of MTPA phytotoxin on yield of potato plants
        3.3.5 Biomass of potato plants
        3.3.6 Chlorophyll content
        3.3.7 Potato seedling root response to MTPA
        3.3.8 Assessment of disease of potato plants
    3.4 Discussion
Chapter 4 Investigation of mechanisms of Rhizoctonia solani phytotoxins in causingpotato stem canker and antioxidant enzyme activities
    4.1 Introduction
    4.2 Materials and methods
        4.2.1 Soil sterilization, potato cultivars, fungal isolates and MTPA
        4.2.2 Experimental design and treatment description
        4.2.3 Data Collected
        4.2.4 Enzymatic assays
        4.2.5 Statistical analysis
    4.3 Results
        4.3.1 Soil physicochemical properties
        4.3.2 Effect of R. solani phytotoxin on stem canker
        4.3.3 Influence of R. solani phytotoxin on black scurf of potato
        4.3.4 Effect of MTPA phytotoxin on MDA content
        4.3.5 Effect of MTPA phytotoxin on SOD activity
        4.3.6 Effect of MTPA phytotoxin on POD activity
        4.3.7 Effect of MTPA phytotoxin on CAT activity
        4.3.8 Effect of MTPA phytotoxin on chitinase activity
        4.3.9 Relationship between the antioxidant enzyme activities and stem canker ofpotato
    4.4 Discussion
Chapter 5 General conclusions and future works
    5.1 General conclusions
    5.2 Future works
References
Acknowledgements
Personal Resume
Publications originating from this dissertation
Supervisor’s Brief Introduction



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