Plant & Microbe Interaction b.stev plant roots

THE “root” of 95% of plants have adapted fungal growth that enhances their survival KNOWN AS: mycorrhizae , it is a beneficial relationship for the fungus as the plant releases some sugars & amino acids from the process of photosynthesis (Wikipedia, 2008)

HOW this help’s the plant : fungus metabolism, provides the plant with phosphate that it can NOT absorb from soil fungus creates a WEB like formation called: a HARTIG NET around & between roots - increases the absorbance: H 2 O/ nutrients - more tolerant & competitive to environment - increased resistance: > drought > poor soil > disease > stresses HARTIG NET : also structure / support to PLANT “ litter layers ” : are formed that encourage the production of enzymes – aids digestion of soil

HOW this help’s the plant :

fungus metabolism, provides the plant with

phosphate that it can NOT absorb from soil

fungus creates a WEB like formation called:

a HARTIG NET around & between roots

- increases the absorbance: H 2 O/ nutrients

- more tolerant & competitive to environment

- increased resistance: > drought

> poor soil

> disease

> stresses

HARTIG NET : also structure / support to PLANT

“ litter layers ” : are formed that encourage the

production of enzymes – aids digestion of soil

2 TYPES of fungal growth on plant root/s : THE growth either: en-sheaths the root , the growth extends into spaced areas of the root cortex ALSO. KNOWN as: [ ectomycorrhizal ] (Wikipedia, 2008)

THE growth either:

en-sheaths the root , the growth extends

into spaced areas of the root cortex ALSO.

KNOWN as: [ ectomycorrhizal ]

cortex FUNGAL SHEATH FUNGAL SHEATH: between cortical cells epidermis section of a PLANT ROOT [ ecto mycorrhizae] (Campbell & Reece, 2005)

epidermis cortex intra cellular hyphae extra cellular hyphae root hair section of a PLANT ROOT [ endo mycorrhizae] arbuscules (Campbell & Reece, 2005)

EPIPHYTIC plant/s DO NOT root in the soil. attach to living plants, ie: tree mosses lichens fungi plants trees ferns

DO NOT root in the soil.

attach to living plants, ie: tree

mosses

lichens

fungi

plants

trees

ferns

DERIVE the physical support from their host & , NUTRIENTS derived from PHOTOSYNTHESIS overgrowth of an EPIPHYTIC PLANT can cause the host to be strangled &THEN replaces the HOST : (number of years) EXAMPLE: climbing plants OR crawlers (Wikipedia, 2008)

RHIZOBIUM a soil microbe that enters the root of plant/s - both aerobic & anaerobic , produces enzymes - stimulates abnormal growth of the root cells: these form into , NODULES on the root METABOLISM of the microbe supplies nitrogen to the plant in a form the plant can then METABOLISE as a nutrient – this phenomenon is called: “ NITROGEN FIXING ROOT NODULE/S ” (Wikipedia, 2008)

a soil microbe that enters the root of plant/s

- both aerobic & anaerobic , produces enzymes

- stimulates abnormal growth of the root cells:

these form into , NODULES on the root

Bibliography Wikipedia. (2008). Rhizobia – wikipedia, the free encyclopedia . Retrieved September 2, 2008, from http://en.wikipedia.org/wiki/Rhizobia Campbell, N., & Reece, J. (2005). Biology (7 th ed.). San Fransisco: Benjamin Cummings Wikipedia. (2008). Mycorrhiza – wikipedia, the free encyclopedia . Retrieved September 2, 2008, from en.wikipedia.org/wiki/ Mycorrhiza - 45k - Wikipedia. (2008). Epiphyte – wikipedia, the free encyclopedia . Retrieved September 2, 2008, from en.wikipedia.org/wiki/Epiphyte – 30k -