Abiotic stress eng

of 26 /26

Embed Size (px)

description

http://www.agrilifehellas.com/images/pdfeng/Abiotic-stress-eng.pdf

Transcript of Abiotic stress eng

  • RADIATION LACK OF WATER

    INTENSITY OF LIGHT PLANT INJURY

    EXTREME TEMPERATURES INFECTION OF PATHOGENS

    OZONE INSECTS

    22 2-DESTRUCTION OF DNA

    PROTEIN-LIPIDS

    STOMATA CLOSE

    GENES EXPRESION DESTRUCTION OF LEAVES

    CELL WALL

    HYPERSENSITIVE

    RESPONSE

    PEROXISOMES

    BIOGENESIS

    SCHEDULE

    CELL DEATH

    BIO-ABIOTIC STRESS

  • Abiotic stress:

    1. Availability of water (drought, floods)

    2. Temperature (hot, cold)

    3. Salinity

    4. O2 concentration

    5. Limiting nutrients (N, P, micronutrients)

    6. Pollution (air, i.e. ozone sulfur dioxide, ground i.e.

    heavy metals)

    7. Radiation (high, low)

    8. The wind

    ABIOTIC STRESS

  • Notability

    Duration

    Degree of exposure

    Combination tensions

    Characteristically

    of intensityVegetable

    characteristically

    Effect Response

    Survival development

    Apoptosis cell death

    Resistance

    Sensibility

    Organ

    or tissue

    with problem

    The stage of

    development

    Genotype

    Abiotic

    stress

    ABIOTIC STRESS

  • ABIOTIC STRESS

    Abiotic stress:

    Abiotic stresses such as drought, salinity and mineral

    toxicity negatively impact growth, development, yield

    and seed quality of plants.

    Similarly, large losses of grain yields in plants occur as

    a result of pathogen attack, in particular during

    vulnerable stages of grain development and

    germination. Stress perception and plant response

    occurs via signal transduction pathways that regulate

    expression of several classes of stress responsive

    genes. Products of these genes include those that are

    directly involved in plant protection and those that fulfill

    regulatory functions.

  • Abiotic stress:

    The first group of the gene products include

    chaperones, osmotins, anti-freeze proteins, mRNA

    binding proteins, enzymes involved in osmolyte

    biosynthesis, water channel proteins, sugar and proline

    transport proteins, detoxification enzymes and a variety

    of proteases, as well as a range of antimicrobial,

    insecticidal and other proteins and peptides.

    The proteins with regulatory function involve

    transcription factors and those that are engaged in

    signal transduction pathways, such as protein kinases

    and hormone biosynthetic enzymes.

    ABIOTIC STRESS

  • Unfavorable conditions

    Stimulus concept

    Signal transduction

    Genes

    expression

    Synthesis of new

    protein families

    Metabolic

    modifications

    Answer

    acclimatization

    Modification

    activity of

    enzymes

    Induced thermo

    proteins

    Depends on

    Intensity of

    stimulus

    Changes in

    genes

    expression

    Availability of water

    ABIOTIC STRESS

  • ROS

    S-HS=S

    Oxydative

    Cell death

    LOO.DNA

    -S=S-

    Mild

    Severity

    damage

    Proteins

    Aminoacids

    Lipids

    ABIOTIC STRESS

  • 1-5% of the total oxygen due to the process deviates

    and converted into active forms of oxygen, which

    causes metabolic effects,

    and destruction of organic molecules such as DNA

    lipids, proteins.

    Especially chloroplasts favored by creating rich micro-

    environment O2 at positions of the water photolysis

    and photosystem II.

    This fact, in conjunction with that chloroplasts are rich

    in pigments makes them extremely sensitive targets.

    ABIOTIC STRESS

    and chloroplasts

  • .Cytochrome

    AREA

    THYLAKOEIDOUS

    ++

    +

    e-

    e-

    e-

    e-

    +

    NADPHNADP

    DP

    PS IIPS I

    +

    +

    CALVIN

    cycle

    CO2Sugars

    plastoquinone

    PQ

    FERREDOXINIS-NADPH reductase

    CONVERSION COMPLEX

    OFOXYGEN

    Light

    PC

    +

    +

    +

    +

    +

    +e-

    e-

    e-

    2

    H2O+

    +

    ABIOTIC STRESS

    and chloroplasts

  • ABIOTIC STRESS

    and photorespiratory cycle

  • The redox potential leads nano-switches and stimulate cells through different biological stages

    Cell division Cell differentiation Apoptosis Death

    Ehc/mV

    Off --Step

    oxidation (+)

    Step

    reduction (-)

    On -

    Schafer and Buettner (2001)

    ABIOTIC STRESS

    and plant phases

  • . . . .4O

    3OOC

    2OSP

    EE

    D R

    EA

    CT

    ION

    Temperature

    ABIOTIC STRESS

    temperatures

    The temperature disrupts the speed of enzymatic

    reactions resulting of biochemical reactions that

    take place slowly; to have the inactivation of

    enzymes; also plant growth slows.

  • --1.Increase in cell size

    Composition of cell wall

    Conductance of stomata

    Synthesis of protein

    Effect on photosynthesis

    Water potential MPa

    --2. --3.

    well

    watered

    medium

    shortage

    of water

    Physiological changes caused by water potential.

    Dehydration.

    --4.

    barren groundClean water

    .

    Concentration of of abscisic

    Concentration of solutes

    ABIOTIC STRESS

    water economy

  • The role of potassium

    H2O H2OH2O

    H2O

    H2O H2O

    H2O

    H2O

    H2OH2O

    K+

    Epidermal

    cells

    ABIOTIC STRESS

    water economy, stomata

    K+

  • Ca++

    +

    ABA

    [Ca++]

    +

    +

    ABA

    [+]

    pH[K+]

    [K+]

    [K+]

    [K+]

    When the water supply is not consistent with the loss (transpiration)

    swelling of the cells can not continue

    the closure of the stomata is critical

    and prevail the need to CO2 and ATP production.

    Photosynthesis is inhibited partially or full.

    ABA (abscisic acid); the phytohormone of stress

    Suspension of

    photosynthesis

    Guard cell

    ABIOTIC STRESS

    water economy, stomata

  • The opening of stomata is regulated by internal factors such as macro-micro nutrients from the concentration of abscisic acid etc. and external humidity as lighting etc.

    Amino acids have a positive effect on the opening of stomata (glutamate acts as an osmo-regulator in guard cells).

    The metabolic balance of the plant is negative when the stomata are closed

    and catabolism is higher than anabolism, growth of the plant stops

    and a general decline of functions.

    ABIOTIC STRESS

    water economy, stomata

  • with increased cellular acidity and reduced amount of

    antioxidants.

    (as the fraction of oxidized glutathione to unbroken)

    chloroplasts are present in the guard cells and the

    amino acid

    glutamate as precursor in the production of

    chlorophyll and regulates plasmolysis opening-close

    favoring opening stomata.

    ABIOTIC STRESS

    water economy, stomata

  • Amino acids have a positive effect on stomatal opening.

    (glutamate acts as an osmo-regulator in guard cells)

    Proline inhibits the action of abscisic and increases the

    action of gibberellins.

    When abiotic stress have increased acidity and reduced

    cellular amount of antioxidants such as the fraction of

    oxidized glutathione to opened glutathione.

    ABIOTIC STRESS

    and osmolytes

  • Many plants assemble betaines and proline at high

    temperature, salinity and drought.

    Lack of water leads to concentration of glycine betaine to

    the leaves other small compounds that act as osmo-

    regulators the amino acids is precursors in the

    production of betaines (the hydroxyl groups of the

    methylated)

    Typical betaines, amino acids are alanine, proline,

    glycine

    H

    H

    H

    CH3

    CH3CH3

    Glycine betaineH

    H

    H

    Glycine

    ABIOTIC STRESS

    and osmolytes

  • ANALYSIS OF TROUBLE BY SALINITY

    What is the effect of salt concentration in plants and accumulation of amino acid proline;

    Can these results support the hypothesis that plants accumulate proline to achieve osmotic balance in saline soils;

    Accum

    ula

    tion o

    f am

    ino a

    cid

    ssalt concentration

    Other aminoacidsproline

    Graph of the level of amino acids in different

    salinities.

    ABIOTIC STRESS

    and osmolytes

  • The effect osmotically active molecules (stored in the vacuole) Na +, K + to denaturation of the protein and the enzyme activity of the osmolyte proline (accumulates in cytoplasm)

    +

    +

    +

    +

    +

    +

    Pro

    +

    Order hydration

    Of protein

    Disorder hydration

    of protein

    Proline and

    operating configuration

    Disorder functional configuration

    Protein (Denaturation)

    Pro

    Pro

    Pro

    Pro

    Pro

    Pro

    Pro

    Pro

    Pro

    ProProPro

    Proline and

    Protection from dehydration

    ABIOTIC STRESS

    and osmolytes

  • + +

    protein

    without folding

    protein

    with folding

    Chaperonins

    ABIOTIC STRESS

    and chaperons

  • Progenetics

    Apply the agro-technology and obtained

    new active substances for the plants

    that confer adaptation mechanisms

    following new signaling pathways

    which lead to a different way

    expression of the genes.

    The problem addressed by different angles

    give a complete solution.

  • For more information

    AgriLife Hellas.com

    A SMALL BEGINNING IN BIG ISSUE