STRESUL HIDRIC LA PLANTE Prezentare realizata in cadrul proiectului POS CCE - A2-O 2.1.2-2009-2 ID.524, cod SMIS-CSMR 11986 CERCETARI PRIVIND SEMNIFICATIA RELATIEI DINTRE RASPUNSUL GENOMIC, METABOLISMUL FENOLPROPANILOR SI FOTOSINTEZA IN CONDITII DE STRES ABIOTIC PENTRU OPTIMIZAREA POTENTIALULUI BIOSINTETIC LA SOIURI DE ZMEUR SI MUR
Stresul hidric la plante. Prezentare realizata in cadrul proiectului POS CCE - A2-O 2 .1.2-2009-2 ID.524, cod SMIS-CSMR 11986 - PowerPoint PPT Presentation
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STRESUL HIDRIC LA PLANTE
Prezentare realizata in cadrul proiectului POS CCE - A2-O 2.1.2-2009-2 ID.524, cod SMIS-CSMR 11986
CERCETARI PRIVIND SEMNIFICATIA RELATIEI DINTRE RASPUNSUL GENOMIC, METABOLISMUL FENOLPROPANILOR SI
FOTOSINTEZA IN CONDITII DE STRES ABIOTIC PENTRU OPTIMIZAREA POTENTIALULUI
BIOSINTETIC LA SOIURI DE ZMEUR SI MUR
Raspunsul plantelor la factorul de stress de stress
Seceta include urmatoarele conditii:Deficit hidric al soplului , este cauzat de lipsa precipitatiilor si lipsa apei disponibile in sol.Deficit hidric al aerului , RH<20% in atmosfera, transpiratia>>absorbtia apei
Tipul salbatic si mutante ABA-deficient de porumb cultivate in conditii normale si deficitare de apa
of
gro
wth
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Deficitul hidric provoaca abscizia frunzelor
Leaves of young cotton plants abscise in response to water stress
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… inchiderea stomatelor mediata de ABA
ROS – reactive oxygen species
PLC – phospholipase C
cADPR – cyclic ADP-ribose
IP3 – inositol triphosphate
PLC – phospho-lipase D
NO – Nitric oxide
PA – Phosphopatidic acid
R – Receptor
S1P – Spingosine-1- Phosphate
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Deficitul hidric scade rata fotosintezeiEfectul deficitului hidric asupra cresterii
frunzelor si a ratei fotsintezei la floarea soarelui
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Water stress affects translocation of nutrientsRelative effects of water stress on photosynthesis and translocation in sorghum
Plants exposed to 14CO2 for a short time interval. Radioactivity fixed in the leaf taken as a measure of photosynthesis, and loss of radioactivity after removal of 14CO2 taken as a measure of rate of assimilate translocation.
A =gs ( Ca-Ci)A =gm (Ci-Cc)
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How does drought cause the generation of ROS?
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How does drought cause the generation of ROS?
3P680*
3O2 1O2*
O2 •O2– H2O2
SOD
SOD – Superoxide Dismutase
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Fates of sunlight absorbed in the light-harvesting chlorophyll complexes
P – photochemistry (green)D – safe dissipation of excess excitation energy as heat (red)F – fluorescence3T – triplet pathway, leading to the formation of singlet oxygen (1O2*) and photo-oxidative damage
Demmig-Adams & Adams III 2000 Nature 403: 371
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Actiunea ROS asupra celulelor
3. Scavenging ROS
Enzymes:1) SOD( superoxide dismutase)2) POD (AscorbatPeroxidase)3) CAT (Catalase)
Oxidants:1) carotene2) Vit E3) Vit C 4) GSH5) phenolics