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if temperature Burst if dark BAMnut model Azam Ali Sayed et by HC120221214436

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									Photosynthesis

       • What is it ?

       • Where it occurs ?

       • How ?

       • How is its important ?

       • How to measure ?
   Photosynthesis ประกอบด้วย 3 กระบวนการย่อย
• CO2 diffusion
 A = Cg d[CO2]

• Photochemical process (light reaction)
4H2O + 2ADP+2NADP+ +2pi
  O2+2H2O+2ATP+2NADPH +2H+

• Biochemical process
3CO2+9ATP+6NADPH+6H+                  triose-
  P+6NADP+9ADP+8Pi+3H2O
   The overall chemical reaction
  • CO2 + 2H2O                (CH2O) + H2O + O2

   H2O      light / atenna                 O2 + H+ +Pi


ADP +Pi +NADP+       PSII PSI Cytochrome   ATP + NADPH

   CO2        enzymes/ stroma                 (CH2O)
           RuBPcarboxylase : CO2receptor
          CHLOROPLAST

• 1- 10 mm

• Lamellae (membranes) : light reaction
  – stroma lamella (double lamella)
  – grana lamella (stacked lamella)


• Stroma : dark reaction
Leaf anatomy of C3 vs. C4 plants
  Chloroplast and
Chlorophyll structure
       Electron transportation

• Chlorophyll a ,b Carotenoid

• Reaction centers : absorbed PHOTONS
  from light energy

• PSII : ground stage           excited stage

• PSI : Q , Photophosphorylation
 Energy diagram of the photosynthetic
 electron transport system
      Light                        Light


              Chlorophyll a/b              Chlorophyll a


              P680 Electron transfer       P700 Electron transfer
O2
                                                                NADPH

                       ATP
H2O

      Photosystem II                   Photosystem I
Energy diagram of the photosynthetic electron transport
Redox potential                                Fd-Ub
-800
                                                         e-        NADP+
-600
                                                              Fd
-400

-200
                     Q                   Solar e-         NADPH
  0
                                         radiation
                              e-
 200
         Solar
                    -
         radiation e ADP             Cty f    Photo
 400
                                   ATP        system I
 600              Photo
 800   H2O        system II
                         H+
                                                          CO2
                     O2                                   reduction
        Radiation vs Photons
• E = hv = speed of light/wave length
• E = energy content of the quantum (J/quantum)
• h = Planck ‘s constant (6.626 x 10-34 J s)

400 500       600   700 (nm)
 25  20        16.7 14.3 (x103 cm-1)
 7.5  6         5    4.5 (x1014 s-1)
 5    4         3.3  2.9 (x10-19 J quantum-1)
     Conversion factors for energy units
              used in the text
•   1 electron volt (eV)       =      1.602 x 10-19 J
•   1 watt                     =      1 J s-1
•   1 kWh                      =      3.6 x 106 J
•   1 Joule                    =      0.239 calories
•                              =      6.242 x 1018 eV
•   1 cal.                     =      4.184 J
•   1 kJ mol quantum -1        =      1.036 x 10-2 eV
•   Plank’s constant           =      6.62 x 10-34 Js
•                              =      4.136 x 10-15 eVs
•   1 mol quantum of photon contains Avogadro’s number
    6.023 x 1023 particles =   1 Eistein
Radiation & Light
     Carbondioxide fixation
Biomass or Dry weight = Photosynthesis -
  Respiration - Dead - Translocation
Carbon Balance
• C3 species : Calvin cycle ; RUBP    3-PGA
• C4 species : Hatch & Slack cycle ;   PEP
  Oxaloacetic Acid etc.
• Crussulation Acid Metabolism (CAM) : CO2
  fixed during night
C3 vs C4 : Kranz anatomy
       C3 C4 and CAM plant

  PEP Carboxylase                        RuBP Carboxylase
 CO2      C4 Organic acids        CO2   CO2         PGA      (CH2O)


                                                 RUBP
       PEP                   C3 acids


 C3                                              Mesophyll

 C4      Mesophyll                      Bundle sheath

CAM         Dark                            Light
                    พืช C3 vs C4
• ลักษณะทางกายภาพต่ างกัน C3 ไม่ มีVascular sheath แต่
  C4 มี (Kranz anatomy)
• เอนไซม์ PEPase มีความสามารถจับ CO2 ดีกว่ า เอนไซม์
  RUBPase
• C4 มีอัตราการสังเคราะห์ แสงสูงกว่ า C3 (ในสภาพแสงจัด)
• C4 ใช้ พลังงานมากกว่ า C3 ในการตรึง CO2 1 โมเลกุล
• C4 มี RUBP น้ อยกว่ า C3
• C3 ปรับตัวได้ ดีในสภาพ เย็นชืน และ ร้ อนชืน ส่ วน C4 ปรับตัวได้ ดี
                               ้            ้
                            ้
  ในสภาพ ร้ อน แห้ ง หรือ ชืน
• C3 มี Photorespiration ส่ วน C4 ไม่ มี
           Cellular respiration
• The process by which active cells obtain
  energy. It occurs in mitochondria, there are two
  coditions : aerobic & anaerobic respiration.
• The obtained energy was used for maintenance
  and growth of the cell or organ.
• Growth respiration : catabolism provides the
  energy required for biosynthesis and
  constructive reactions leading to form cellular
  products used in the crop growth
    Aerobic respiration has 3 stages :
 C6H12O6 + 6O2                  6CO2 + 6H2O + energy


     Sucrose
                                           NAD+                     O
                                                  e transport       2
                  Pyruvic                            chain
 Glycolysis                   TCA
                    acid    Krebs’ cycle             Oxidative
                                                  phosphorylation

                                           NADH                     H2O
NADH+,         NADH,
 ADP            ATP
                  Respiration
• MITOCHONDRIA

• C6H12O6 + 6O2           6CO2 + 6H2O +637 kcal

• Glycolysis : anaerobic respiration

• aerobic respiration : Krebs cycle ; Oxidative
  phosphorylation

• Electron transport chain : ATP, NADPH formed
  and available for other synthesis of other
  moplecules for growth, active transport, and
  metabolic processes.
              Major plant metabolisms
                     STRUCTURAL        STORAGE          ACTIVE CELL
                     compounds         compounds        compounds
                     • cellulose       • starch         • nucleic acids
            O2       • hemicellulose   • fructosans     • enzymes
                     • pentosans       • proteins       • cytochrome
                     • pectin, ect.    • lipids, ect.   • chlorophyll
                                                        • phospholipids,
                                                        ect.
Chloroplast : Photosynthesis
                                   Synthesis / Translocation

                                            Glycolysis            ATP,
  CO2                                                             NADP
                        Mitochondria : Respiration; Krebs cycle

                       O2                                           CO2
Photosynthesis vs Respiration
• Photophosporylation   • Oxidative phosphorylation

• NADPH formed          • NADP formed

• CO2 reduction         • O2 reduction

• CO2 as substrate      • CO2 is product

• H2O as substrate      • H2O is product

• O2 is product         • O2 is substrate

• CH2O is product       • (CH2O)n is substrate and
                          product
Photosynthesis vs   Respiration if …….

  •   Down   • Up      if + O2

  •   Up     • Down    if + CO2

  •   Up     • Up      if + light

  •   Up     • Up      if + temperature

  •   Stop   • Burst   if dark
   ่       ่ ั                ้
เครืองมือทีใช้วดการสังเคราะห์ดวยแสง
                      Ce



               Reference
                                  IRGA
               Analyser


          Co

                              Data logger
                                         Environments
Character of CROPS                       SOIL
                                         CLIMATE
                                         AGRONOMY


                        Water route
   Photosynthesis
                                         Yield potential

                          Etr/Etm
       Pst
                    Pst * Etr/Etm -Res        P pot X HI
                            BAMnut model
(Azam-Ali Sayed et.al, 2001. A Global Mapping Systems for Bambara Groundnut
       Production. FAO Agricultural Information Management Series)


   Water limited                   Weather data               Radiation limited
   growth (WLG)                                                growth (LLG)
                                       seed

                                 Bambara groundnut            Intercepted radiation
     Water uptake

                    Soil water                                        Leaf
                                                     PodW
         Root
                                                                    LeafW
                        RootW                        ShootW

								
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