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Named example of an australian plant response to a pathogen (1 Viewer)

shadowlike04

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Hi, I was wondering if someone could send me a few examples for this dot point. I have this; Phytophthora is a fungal disease that affects Wollemi pine. It causes root lesions which prevents the uptake of water and nutrients from the soil. Insufficient water to the Wollemi causes the discoloration of leaves and wilting. The plant will drop its leaves to conserve energy for fighting the virus but I don't feel like its enough. Thanks!
 

jimmysmith560

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Would the following information be helpful in furthering your response?

Dot point: Investigate the response of a named Australian plant to a named pathogen through practical and/or secondary-sourced investigation, for example:
  • (for the purposes of your response) fungal pathogens
  • viral pathogens
Phytophthora dieback
  • Causative Pathogen:
    • Phytophthora cinnamomi
  • Host Range:
    • Food crop: Avocado, pineapple
    • Other woody/ornamental trees: Fraser firs, shortleaf pines, loblolly pines, azaleas, camellia, boxwood
  • Symptoms:
    • Rot of fine feeder roots
    • Root cankers in some species, leading to dieback and death of host plants.
    • Wilt, stem cankers (with sudden death of tree)
    • Decline in yield
    • Decreased fruit size
    • Gum exudation
    • Collar rot (if infected through grafts near soil level)
  • Control:
    • Cultural control:
      • Alleviation of high soil moisture levels and improving aeration by increasing drainage, and attention to mineral nutrition.
      • The use of mulches rich in cellulose will often reduce populations of P. cinnamomi.
      • Chitosan also inhibits the fungal growth of P. cinnamomi. Gypsum amended soil reduced root rot of avocado seedlings. In hydroponic conditions, increased copper, sand filtration and reduced oxygen significantly reduced disease. Soil solarization, in isolation and with cover crops, significantly reduced P. cinnamomi populations in avocado orchards and sunlight exposure reduced heart rot of pineapple.
    • Biological control:
      • There are numerous microorganisms that inhibit P. cinnamomi via parasitism, antibiosis and competition. Although none of these microorganisms has yet provided economical control, there is increasing evidence that these organisms play an important role in the natural suppression of P. cinnamomi in certain soils.
      • Bioenhanced mulches and repeated applications of the bacterium Pseudomonas putida suppressed P. cinnamomi infection on avocado roots.
      • Earthworms were shown to transport biocontrol agents in potted soil which helped to alleviate avocado root rot.
      • In vitro inhibition of P. cinnamomi was obtained with Byssochlamys nivea isolated from saline mud in western Australia.
    • Chemical Control:
      • Fumigating and certain phosphonate fungistats. A tactic that may be effective, dependent on spores, would be fumigating before planting. However, this would not be effective for eradicating chlamydospores since they are present deeper down in the soil, so fumigation may not reach them.
      • Some experts do not recommend fumigation as P. cinnamomi is often able to re-invade fumigated soil and could cause worse damage since the competing microorganisms in the soil microbial community may be reduced by fumigation.
      • Phosphonate fungistats can improve the ability of a tree to tolerate, resist, or recover from disease by Phytophthora cinnamomi.
      • Phosphite has been used to limit the disease with some success and has been recognized as a major strategy for disease prevention. Phosphite is administered to plants through direct foliage sprays, aerial application by aircraft or via direct injection.
  • Prevention:
    • SPS measures
      • Hygienic precautions can be applied to exclude P. cinnamomi from a place of production. Unsterilized soil or growing medium, or farm machinery, should not be brought in.
      • Introduced plants should be kept apart until their phytosanitary status has been checked and all propagation should be done from healthy plants or seed.
      • Cultural measures should be taken to reduce the risk of spread in case of introduction.
      • If land does become infested, incidence of P. cinnamomi can be reduced, if not necessarily eliminated, by leaving the land under non-susceptible crops for at least 4 years, and by applying various control measures.
    • Public awareness
      • A standard dieback signage system is used in Western Australia to indicate the dieback status of an area to help prevent the spread of propagules by humans.
I hope this helps! :D
 

YourLocalDumbAss

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Would the following information be helpful in furthering your response?

Dot point: Investigate the response of a named Australian plant to a named pathogen through practical and/or secondary-sourced investigation, for example:
  • (for the purposes of your response) fungal pathogens
  • viral pathogens
Phytophthora dieback
  • Causative Pathogen:
    • Phytophthora cinnamomi
  • Host Range:
    • Food crop: Avocado, pineapple
    • Other woody/ornamental trees: Fraser firs, shortleaf pines, loblolly pines, azaleas, camellia, boxwood
  • Symptoms:
    • Rot of fine feeder roots
    • Root cankers in some species, leading to dieback and death of host plants.
    • Wilt, stem cankers (with sudden death of tree)
    • Decline in yield
    • Decreased fruit size
    • Gum exudation
    • Collar rot (if infected through grafts near soil level)
  • Control:
    • Cultural control:
      • Alleviation of high soil moisture levels and improving aeration by increasing drainage, and attention to mineral nutrition.
      • The use of mulches rich in cellulose will often reduce populations of P. cinnamomi.
      • Chitosan also inhibits the fungal growth of P. cinnamomi. Gypsum amended soil reduced root rot of avocado seedlings. In hydroponic conditions, increased copper, sand filtration and reduced oxygen significantly reduced disease. Soil solarization, in isolation and with cover crops, significantly reduced P. cinnamomi populations in avocado orchards and sunlight exposure reduced heart rot of pineapple.
    • Biological control:
      • There are numerous microorganisms that inhibit P. cinnamomi via parasitism, antibiosis and competition. Although none of these microorganisms has yet provided economical control, there is increasing evidence that these organisms play an important role in the natural suppression of P. cinnamomi in certain soils.
      • Bioenhanced mulches and repeated applications of the bacterium Pseudomonas putida suppressed P. cinnamomi infection on avocado roots.
      • Earthworms were shown to transport biocontrol agents in potted soil which helped to alleviate avocado root rot.
      • In vitro inhibition of P. cinnamomi was obtained with Byssochlamys nivea isolated from saline mud in western Australia.
    • Chemical Control:
      • Fumigating and certain phosphonate fungistats. A tactic that may be effective, dependent on spores, would be fumigating before planting. However, this would not be effective for eradicating chlamydospores since they are present deeper down in the soil, so fumigation may not reach them.
      • Some experts do not recommend fumigation as P. cinnamomi is often able to re-invade fumigated soil and could cause worse damage since the competing microorganisms in the soil microbial community may be reduced by fumigation.
      • Phosphonate fungistats can improve the ability of a tree to tolerate, resist, or recover from disease by Phytophthora cinnamomi.
      • Phosphite has been used to limit the disease with some success and has been recognized as a major strategy for disease prevention. Phosphite is administered to plants through direct foliage sprays, aerial application by aircraft or via direct injection.
  • Prevention:
    • SPS measures
      • Hygienic precautions can be applied to exclude P. cinnamomi from a place of production. Unsterilized soil or growing medium, or farm machinery, should not be brought in.
      • Introduced plants should be kept apart until their phytosanitary status has been checked and all propagation should be done from healthy plants or seed.
      • Cultural measures should be taken to reduce the risk of spread in case of introduction.
      • If land does become infested, incidence of P. cinnamomi can be reduced, if not necessarily eliminated, by leaving the land under non-susceptible crops for at least 4 years, and by applying various control measures.
    • Public awareness
      • A standard dieback signage system is used in Western Australia to indicate the dieback status of an area to help prevent the spread of propagules by humans.
I hope this helps! :D
@Hivaclibtibcharkwa has some competition,i see 👀
 

shadowlike04

Member
Joined
Aug 9, 2021
Messages
29
Gender
Male
HSC
2022
Would the following information be helpful in furthering your response?

Dot point: Investigate the response of a named Australian plant to a named pathogen through practical and/or secondary-sourced investigation, for example:
  • (for the purposes of your response) fungal pathogens
  • viral pathogens
Phytophthora dieback
  • Causative Pathogen:
    • Phytophthora cinnamomi
  • Host Range:
    • Food crop: Avocado, pineapple
    • Other woody/ornamental trees: Fraser firs, shortleaf pines, loblolly pines, azaleas, camellia, boxwood
  • Symptoms:
    • Rot of fine feeder roots
    • Root cankers in some species, leading to dieback and death of host plants.
    • Wilt, stem cankers (with sudden death of tree)
    • Decline in yield
    • Decreased fruit size
    • Gum exudation
    • Collar rot (if infected through grafts near soil level)
  • Control:
    • Cultural control:
      • Alleviation of high soil moisture levels and improving aeration by increasing drainage, and attention to mineral nutrition.
      • The use of mulches rich in cellulose will often reduce populations of P. cinnamomi.
      • Chitosan also inhibits the fungal growth of P. cinnamomi. Gypsum amended soil reduced root rot of avocado seedlings. In hydroponic conditions, increased copper, sand filtration and reduced oxygen significantly reduced disease. Soil solarization, in isolation and with cover crops, significantly reduced P. cinnamomi populations in avocado orchards and sunlight exposure reduced heart rot of pineapple.
    • Biological control:
      • There are numerous microorganisms that inhibit P. cinnamomi via parasitism, antibiosis and competition. Although none of these microorganisms has yet provided economical control, there is increasing evidence that these organisms play an important role in the natural suppression of P. cinnamomi in certain soils.
      • Bioenhanced mulches and repeated applications of the bacterium Pseudomonas putida suppressed P. cinnamomi infection on avocado roots.
      • Earthworms were shown to transport biocontrol agents in potted soil which helped to alleviate avocado root rot.
      • In vitro inhibition of P. cinnamomi was obtained with Byssochlamys nivea isolated from saline mud in western Australia.
    • Chemical Control:
      • Fumigating and certain phosphonate fungistats. A tactic that may be effective, dependent on spores, would be fumigating before planting. However, this would not be effective for eradicating chlamydospores since they are present deeper down in the soil, so fumigation may not reach them.
      • Some experts do not recommend fumigation as P. cinnamomi is often able to re-invade fumigated soil and could cause worse damage since the competing microorganisms in the soil microbial community may be reduced by fumigation.
      • Phosphonate fungistats can improve the ability of a tree to tolerate, resist, or recover from disease by Phytophthora cinnamomi.
      • Phosphite has been used to limit the disease with some success and has been recognized as a major strategy for disease prevention. Phosphite is administered to plants through direct foliage sprays, aerial application by aircraft or via direct injection.
  • Prevention:
    • SPS measures
      • Hygienic precautions can be applied to exclude P. cinnamomi from a place of production. Unsterilized soil or growing medium, or farm machinery, should not be brought in.
      • Introduced plants should be kept apart until their phytosanitary status has been checked and all propagation should be done from healthy plants or seed.
      • Cultural measures should be taken to reduce the risk of spread in case of introduction.
      • If land does become infested, incidence of P. cinnamomi can be reduced, if not necessarily eliminated, by leaving the land under non-susceptible crops for at least 4 years, and by applying various control measures.
    • Public awareness
      • A standard dieback signage system is used in Western Australia to indicate the dieback status of an area to help prevent the spread of propagules by humans.
I hope this helps! :D
These are good examples for the control/prevention of the plant disease but they all require human assistance. I'm looking for the actual response whether it be physical or chemical that is initiated by the plant itself. Thanks for the information though.
 

okayokay123

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What I also have for the fungal response for the waratah
*secretion of antifungal enzymes
*controlled cell death of infected roots, stems, or leaf cells
*strengthening of cell walls to prevent further penetration

I would expand on that in the exam, obviously
 

zizi2003_

Well-Known Member
Joined
Dec 18, 2020
Messages
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HSC
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These are good examples for the control/prevention of the plant disease but they all require human assistance. I'm looking for the actual response whether it be physical or chemical that is initiated by the plant itself. Thanks for the information though.
plant wilting itself is a response for phytophthora infestans (rapid active response)
others include the release of hydrogen peroxide (chemical defence) as well as cell wall apposition to prevent the growing fungal hyphae from penetrating cells for the same disease in wollemi plants
 

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