slide1 n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Plant-Microbe Interactions PowerPoint Presentation
Download Presentation
Plant-Microbe Interactions

Loading in 2 Seconds...

play fullscreen
1 / 27

Plant-Microbe Interactions - PowerPoint PPT Presentation


  • 424 Views
  • Uploaded on

Plant-Microbe Interactions. SUMBER: culter.colorado.edu/~ kittel /Slides18_13Nv07. ppt ‎. INTERAKSI TANAMAN-MIKROBA. Plant-microbe interactions diverse – from the plant perspective: Negatif – e.g. Parasitis / Pathogenik Neutral Positif – Simbiotik.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Plant-Microbe Interactions' - santo


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

Plant-Microbe Interactions

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide2

INTERAKSI TANAMAN-MIKROBA

  • Plant-microbe interactions diverse – from the plant perspective:
    • Negatif– e.g. Parasitis/ Pathogenik
    • Neutral
    • Positif– Simbiotik
  • Pokokbahasan important positive interactions with respect to plant abundance and distribution – related to plant nutrient and water supply:
    • Dekomposisi BOT
    • Mycorrhizae
    • Fiksasi N2
    • Rhizosphere

Perananinteraksiinidalamsiklus N

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide3

I. DekomposiBahanOrganik

  • Input rates –
    • Generally follow rates of production
    • Deciduous = evergreen
  • Pemasokutamaharatanaman – terutama N & P
  • Bahanmentah
  • Soil organic matter derived primarily from plants –
    • Mainly leaves and fine roots
    • Wood can be important component in old growth forests

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide4

B. Proses-Proses

nematode

termites

springtail (Isotoma viridis)

  • 1. FragmentasiBahanOrganik
    • Breakdown of organic matter (OM) into smaller bits = humus
    • By soil ‘critters’ – including nematodes, earthworms, springtails, termites
      • consume and excrete OM  incomplete digestion

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide5

2. MineralisasiBahanOrganik

    • Breakdown OM senyawa an-organik
    • Microbial process: accomplished by enzymes excreted into the soil

For Nitrogen

energy for heterotrophic bacteria

Mineralization

Ammonium

NH4+

proteins

(insoluble)

amino

acids

proteases

Immobilization

Nitrification

Nitrite

NO2-

energy for

nitrifying bacteria*

Microbial uptake

Nitrate

NO3-

Plant uptake

  • * In 2 steps by 2 different kinds of bacteria – (1) Nitrosomonas oxidize NH3 to nitrites + (2) Nitrobacter oxidize nitrites to nitrates

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide6

C. Serapan N olehTanaman– Chemical form taken up can vary

mineralization

Protein

NH4+

NO3-

SerapanTanaman

  • 1) Nitrate (NO3-)
    • Lebihdisenangiolehtanaman, lebihmudahdiserap
    • Even though requires conversion to NH4+before be used  lots of energy
    • vs. taking up & storing NH4+ problematic
      • More strongly bound to soil particles
      • Acidifies the soil
      • Not easily stored
  • 2) Ammonium (NH4+ ) –
    • Digunakanlangsungolehtanamandalamtanah yang nitrifikasinyalambat (mis. Tanah basah)

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide7

3) Beberapajenistanamanmenyerapsedikitasam amino (mis. glycine)

    • Circumvents the need for N mineralization
    • Difasilitasiolehadanyamycorrhiza

proteins

mineralization

NH4+

amino

acids

immobilization

nitrification

microbial uptake

NO3-

Penyerapanlangsung

SerapanTanaman

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide8

D. KontrolthdKecepatanDekomposisi BO

  • Temperature –
    • Warmer is better
    • <45°C
  • 2) Moisture – intermediate is best
    • Too little  desiccation
    • Too much  limits O2 diffusion

RespirasiMikroba Tanah

T

Soil Moisture %

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide9

3) FaktorTanaman – Kualitasbiomasaseresah

Decomposition rate

as fn(lignin, N)

Deciduous forest spp

  • b) Material strukturaltanaman
    • Lignin – complex polymer, cell walls
      • Confers strength with flexibility
      • – e.g. oak leaves
      • Relatively recalcitrant
      • High conc.  lowers decomposition
  • a) Rasio C:N biomasaseresah( = Konsentrasi N)
    • If C relative to N high  N limits microbial growth
      • Immobilization favored
      • N to plants 

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide10

OH

R

c) Senyawasekundertanaman

  • Anti-herbivore/microbial
  • Common are phenolics – e.g. tannins
    • – Aromatic ring + hydroxyl group, other compounds
  • KontroldekomposisiBahanorganikoleh:
    • Bind to enzymes, blocking active sites lower mineralization
    • N compounds bind to phenolicsgreater immobilization by soil
    • Phenolics C source for microbes greater immobilization by microbes

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide11

II. Mycorrhiza = JamurAkar

  • HubunganSimbiotikantaratanaman (akar) & fungi tanah
    • Plant provides fungus with energy (C)
    • Fungus enhances soil resource uptake
    • Penyebarannya:
    • Occurs ~80% angiosperm spp
    • All gymnosperms
    • Sometimes an obligaterelationship.

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide12

KelompokutamaMycorrhiza:

  • 1) Ectomycorrhiza–
    • Fungus forms “sheath” around the root (mantle)
    • Grows in between cortical cells = Hartig net – apoplastic connection
    • Occur most often
    • in woody spp

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide13

2) Endomycorrhiza–

    • Fungi menembussel-selakar

Arbuscule in plant cell

  • Common example is arbuscularmycorrhizae (AM)
    • Found in both herbaceous & woody plants
    • Arbuscule = exchange site

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide14

C. FungsiMycorrhiza:

    • Perananpenghubungtanaman-tanah:
      • Increase surface area & reach for absorption of soil water & nutrients
  • Increase mobility and uptake of soil P
  • Provides plant with access to organic N
  • Protect roots from toxic heavy metals
  • Protect roots from pathogens
  • Efekharatanahthdmycorrhiza
    • Intermediate soil P concentrations favorable
      • Extremely low P – poor fungal infection
      • Hi P – plants suppress fungal growth
        • – taking up P directly
    • Kejenuhan N

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide15

III. Fikisasi N2

  • N2 abundant – chemically inert
  • N2 must be fixed = converted into chemically usable form
    • Lightning
    • High temperature or pressure (humans)
    • Biologically fixed
  • Nitrogenase– EnsimKatalisisN2 NH3
  • Expensive process – ATP, Molybdenum
  • Anaerobik : Memerlukanstrukturkhusus

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide16

A. Hanyaterjadipadaorganisme Prokaryote:

  • Bacteria (e.g. Rhizobium, Frankia)
  • Cyanobacteria (e.g. Nostoc, Anabaena)
  • Free-living in soil/water – heterocysts
  • Symbiotic with plants – root nodules
  • Loose association with plants

Anabaena with heterocysts

  • Simbiosisdengantumbuhan– Mutualism
    • Prokaryote receives carbohydrates
      • Plant may allocate up to 30% of its C to the symbiont
    • Tumbuhanmenyediakantapakanaerobik – Bintilakar
    • Tumbuhanmenerima N

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide17

soybean

root

  • Contohsistemsimbiotikfiksasi N2olehtumbuhan
    • Legumes (Fabaceae)
      • Widespread
      • bacteria = e.g., Rhizobiumspp.
  • Those with N2-fixing symbionts form root “nodules”
  • – anaerobic sites that “house” bacteria

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide18

Problem Toksisitas O2

    • Symbionts regulate O2 in the nodule with leghemoglobin
      • Different part synthesized by the bacteria and legume

Cross-section of nodules of soybean nodules

  • Symbiontsmengendalikan O2dalambintilakardenganmembentukleghemoglobin
    • An oxygen carrier (in legumes) to prevent oxygen toxicity for the bacterium
    • different pieces synthesized by the bacteria (heme) and in the plant (protein)

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide19

2) Simbiosistumbuhan Non-legume:

    • “Actinorhizal”= associated with actinomycetes (N2-fixing bacteria)
      • genus Frankia
    • Usually woody species – e.g. Alders, Ceanothus

Ceanothus velutinus - snowbrush

Ceanothus roots, with

Frankia vesicles

Bacteria in root or small vesicles

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide20

(2) Simbiosistumbuhan Non-legume

“Actinorhizal”= associated with actinomycetes (N2-fixing bacteria)

genus Frankia

Usually woody species – e.g. Alders, Ceanothus

Bacteria occur in root or small vesicles

Buffaloberry (Shepherdiaargentea)

- actinorhizal shrub (Arizona)

  • Bacteria in root or small vesicles

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide21

B. MaknaEkologisFiksasi N2

  • (1). Important in “young” ecosystems –
    • Young soils low in organic matter, N
  • Ecological importance of N2 fixation
  • (1) Most important in “young” ecosystems (early in primary succession) -
  • young soils are low in organic matter, and thus N, which is often a limiting nutrient for plant growth
  • e.g., newly exposed (glaciated) or newly laid down rock (volcanic),
  • recently denuded landscapes(human activities, directly or indirectly – bulldozing, erosion

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide22

2) Plant-level responses to increased soil N conc:

  • Some plants (facultative N-fixers) respond to soil N concentration 
    • Plant shifts to direct N uptake
    • N fixation 
    • Number of nodules decreases
  • Plant-level: responses on N-fixing plants to high soil N conc:
  • In some plants (facultative N-fixers) –
    • As N conc, N fixation decreases
    • Plant shifts to direct N uptake
    • #nodules decreases

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide23

3) Kompetisi: Interaksitumbuhanfiksasi N

  • N2-fixing plants higher P, light, Mo, and Fe requirements
    •  Poor competitors
    • Competitive exclusion less earlier in succession
    • Though - N2 fixers in “mature” ecosystems
  • Competition – N-fixers and plant community interactions
  • because N2 fixing plants have higher P, light, Mo, and Fe requirements .
  • They are believed to be poor competitors;
  • chances for competitive exclusion lower earlier in succession (although there are N2 fixers in “mature” ecosystems)
    • e.g. of plants important in early stages of succession:
    • lupines, alders, clovers, Dryas

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide24

PLANT

REMAINS

PLANT

Natural N cycle

  • IV. Kehilangan N dariekosistem
    • Leaching  to aquatic systems
    • Kebakaran Penguapan
    • Denitrifikasi N2, N2O to atmosfir
    • – Closes the N cycle!
      • Bacteria mediated
      • Anaerobik.

N2O

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

slide25

Fertilizer

80

Legumes, other plants

40

Fossil fuels

20

Biomass burning

40

Wetland draining

10

Land clearing

20

Total from human sources

210

Annual release(1012 g N/yr)

NATURAL SOURCES

Soil bacteria, algae, lightning, etc.

140

ANTHROPOGENICSOURCES

Annual release(1012 g N/yr)

Altered N cycle

Annual release of fixed N2 (1012 g = teragram, trillion gr)

Source: Peter M. Vitouseket al., "Human Alteration of the Global Nitrogen Cycle: Causes and Consequences," Issues in Ecology, No. 1 (1997), pp. 4-6.

From - Peter M. Vitouseket al., "Human Alteration of the Global Nitrogen Cycle - Causes and Consequences," Issues in Ecology, No. 1 (1997), pp. 4-6.

slide26

V. InteraksiRhizosphere

    • Jaring-jaringmakananbawahtanah

Fine root

  • Zone within 2 mm of roots – hotspot of biological activity
  • Roots exude C & cells slough off = lots of goodies for soil microbes  lots of microbes for their consumers (protozoans, arthropods)
  • “Free living” N2-fixers thrive in the rhizosphere of some grass species

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎

ringkasan
RINGKASAN
  • Plant–microbial interactions play key roles in plant nutrient dynamics
    • Decomposition –
      • mineralization, nitrification …
      • immobilization, denitrification …
    • Rhizosphere – soil foodweb
    • Mycorrhizae – plant-fungi symbiosis
    • N fixation – plant-bacteria symbiosis
  • Highly adapted root morphology and physiology to accommodate these interactions
  • N cycle, for example, significantly altered by human activities

SUMBER: culter.colorado.edu/~kittel/Slides18_13Nv07.ppt‎