Post on 06-Apr-2016
description
RADIATION LACK OF WATER
INTENSITY OF LIGHT PLANT INJURY
EXTREME TEMPERATURES INFECTION OF PATHOGENS
OZONE INSECTS
Η2Ο2 Ο2-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
ΑΤΡ
Η+Η+
Η+Ρι
e-
e-
e-
e-
Η+
NADPHNADP
ΑDP
PS IIPS I
Η+
Η+
CALVIN
cycle
CO2Sugars
plastoquinone
PQ
FERREDOXINIS-NADPH reductase
CONVERSION COMPLEX
OFOXYGEN
Light
PC
Η+
Η+
Η+
Η+
Η+
Η+
e-
e-
e-
Ο2
H2OΗ+
Η+
ABIOTIC STRESS
and chloroplasts
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++
Κ+
ABA
[Ca++]
Κ+
Κ+
ABA
[Η+]
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
ΓΛΥΣΙΝΗH
H
H
ΓΛΥΣΙΝΗCH3
CH3
CH3
Glycine betaineΓΛΥΣΙΝΗH
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)
Να+
Να+
Να+
Να+
Να+
Να+
Pro
Να+
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
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.