外源脱落酸缓解生菜镉胁迫的机理研究

发布时间：2022-02-09 19:21

　　镉(Cd²⁺)是一种剧毒非必需元素,对全球农作物生产和人类健康构成严重威胁。为了研究外源脱落酸（ABA）是否可以缓解Cd²⁺胁迫并且提高Cd²⁺敏感型生菜（Lactuca sativa L）品种的食品安全性,我们开展了以下试验:1)第一个试验比较了十个生菜品种（意大利,欧歌,四季,绿梦,碧羽衣,美国,陇盛,美惠子,绿速和安研）的Cd²⁺积累能力和食品安全潜力;2)在第二个试验中,确定了筛选的四种生菜品种（绿速,绿梦,意大利和安研）对Cd²⁺胁迫的根系耐受性和生化响应;3)在第三个试验中,研究了叶面施用ABA对Cd²⁺敏感型生菜（绿速）生理生化、与ABA,赤霉素（GA3）,吲哚-3-乙酸（IAA）,细胞分裂素（CTK）合成相关的基因相对表达以及生物量和叶片镉含量的影响。所有试验均在温室育苗,然后转移至水培营养液中在气候控制室中进行处理。试验结果表明:1)0.1μM CdCl₂九个生菜品种的叶片干生物量降低了4.1-12.6%。然而,绿梦... 

【文章来源】：甘肃农业大学甘肃省

【文章页数】：114 页

【学位级别】：博士

【文章目录】：
SUMMARY
摘要
CHAPTER ONE 1.0. Literature Review
    1.1. Plant abiotic stress and effect of heavy metals on plants
    1.2. Cadmium uptake and its transport in plants
    1.3. Effect of cadmium on plants
    1.4. Bio-indicators of the level of stress in plants
    1.5. Plants tolerance mechanisms to heavy metal stress
        1.5.1. Antioxidant defense system in plants
        1.5.2. Role of endogenous hormones
        1.5.3. ABA synthesis and alleviation of heavy metal stress in plants
        1.5.4. Expression of genes in plants under heavy metal stress
    1.6. Strategies for managing cadmium stress in plants
        1.6.1 Use of tolerant cultivars
        1.6.2. Application of exogenous plant growth regulators
        1.6.3. ABA biosynthesis and its application in managing heavy metal stress
        1.6.4. Use of grafted materials
        1.6.5. Plant nutrition and alleviation of Cd stress in plants
        1.6.6. Use of organic soil amendments in alleviating Cd stress in plants
    1.7. Problem statement
    1.8. Justification/Significance of the study
    1.9. Research hypotheses
    1.10. Objectives of the study
CHAPTER TWO 2.0. Cadmium bioaccumulation and safety potentials of ten Chinese lettuce (Lactuca sativa L.)genotypes grown in Cd~(2+)-contaminated hydroponic nutrient solution
    2.1. Introduction
    2.2 Materials and Methods
        2.2.1. Genotypes used for the experiment
        2.2.2. Seed germination and seedling growth
        2.2.3. Treatments and experimental design
        2.2.4. Measurement of growth indexes
        2.2.5. Analysis of cadmium contents
        2.2.6. Statistical analysis
    2.3. Results
        2.3.1 Main effects of genotype and cadmium on growth indexes
        2.3.2 Effect of variety and cadmium on chlorophyll (SPAD value), fresh and dry leaf biomass and contents of Cd in the plants
        2.3.4. Correlation analysis for vegetative characteristics and cadmium contents
    2.4. Discussion
    2.5 Conclusion
CHAPTER THREE 3.0. Root tolerance and biochemical response of Chinese lettuce (Lactuca sativa L.) Genotypes to cadmium stress
    3.1. Introduction
    3.2. Materials and Methods
        3.2.1. Genotypes used for the experiment
        3.2.2. Seedling growth conditions
        3.2.3. Experimental design and treatments
        3.2.4. Data measurements
        3.2.5. Statistical analysis
    3.3. Results
        3.3.1. Root morphological characteristics
        3.3.2. Root tolerance to cadmium stress
        3.3.3. Contents of H_2O_2 in roots
        3.3.4. Contents of root hormones
        3.3.5. Correlation analysis
        3.3.6. Antioxidant enzymes activities and proline contents
    3.4. Discussion
    3.5 Conclusion
CHAPTER FOUR 4.0. Foliar application of Abscisic acid mitigates cadmium stress and increases food safety of cadmium-sensitive lettuce (Lactuca sativa L.) genotype
    4.1. Introduction
    4.2. Materials and Methods
        4.2.1. Plant materials and growth conditions
        4.2.2. Experimental design and treatments
        4.2.3. Data measurements
    4.3. Results
        4.3.1. Hydrogen peroxide (H_2O_2) and malondialdehyde (MDA) contents
        4.3.2. Antioxidant enzymes activities
        4.3.3. Chlorophyll (Chl) and carotenoids contents
        4.3.4. Gas exchange parameters
        4.3.5. Relative water content (RWC) of leaf
        4.3.6. Expressions of genes related to signal transduction of ABA, GA3, IAA and CTK
        4.3.7. Macro and micro nutrient elements
        4.3.8. Cadmium contents
        4.3.9. Biomass, biomass response to stress (BRS) and morphology of lettuce plants
    4.4. Discussion
    4.5 Conclusion
CHAPTER FIVE
    5.0. General conclusions
    5.1. Innovation
    5.2. Recommendations
REFERENCES
APPENDICES
ACKNOWLEDGEMENTS
DEDICATION
BRIFE INTRODUCTION OF AUTHOR
BRIFE INTRODUCTION OF SUPERVISOR


【参考文献】：
期刊论文
[1]氯化镉对葡萄根系线粒体特性与根系活力的影响[J]. 邵小杰,杨洪强,乔海涛,张龙,由淑贞.  应用生态学报. 2009(06)
[2]Combined toxicity of copper and cadmium to six rice genotypes （Oryza sativa L.）[J]. HUANG Yizong, HU Ying, LIU Yunxia Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China..  Journal of Environmental Sciences. 2009(05)
[3]盐地碱蓬过氧化氢酶基因的克隆及盐胁迫下的表达分析(英文)[J]. 马长乐,王萍萍,曹子谊,赵彦修,张慧.  Acta Botanica Sinica. 2003(01)



本文编号：3617518