Plant & Microbe Interaction - plant roots

Plant & Microbe Interaction

b.stev

plant roots

THE “root” of 95% of plants have adapted fungal growth that enhances their survival

KNOWN AS:KNOWN AS:

mycorrhizae, it is a beneficial relationship

for

the fungus as the plant releases somesome

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: H2O/ nutrients - more tolerant & competitive to environment - increased resistance: > droughtdrought > poor soilpoor soil > diseasedisease > stresses 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: [ectomycorrhizalectomycorrhizal]

(Wikipedia, 2008)

cortex

FUNGAL SHEATH

FUNGAL SHEATH:

between cortical cells

epidermis

section of a PLANT ROOT

[ectomycorrhizae]

(Campbell & Reece, 2005)

epidermis

cortex

intracellular hyphae

extracellular hyphae

root hair

section of a PLANT ROOT

[endomycorrhizae]

arbuscules

(Campbell & Reece, 2005)

EPIPHYTIC plant/s

DO NOT root in the soil. attach to living plants, ie: treetree

o mosseso lichenso fungi

o plantso treeso ferns

DERIVE the physical support from their

host

&, NUTRIENTS derived from

PHOTOSYNTHESISovergrowthovergrowth of an EPIPHYTIC PLANT

can cause the host to be strangledstrangled

&THEN replaces the HOST : (number

of years)

EXAMPLE: climbing plants OR

crawlers(Wikipedia, 2008)

RHIZOBIUMa soil microbemicrobe that enters the root of plant/s

- both aerobic & anaerobic, produces enzymes

- stimulates abnormal growth of the root cells: these form into, NODULES NODULES on the root

METABOLISM of the microbemicrobe 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)

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 (7th 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 -