Talk:Plant disease resistance

This article was part of an assignment from Saint Louis University in Spring 2013 (see the course page for more details).

Coevolution Section

I think that it would be beneficial if information about coevolution between host plants and pathogens were included. It is important to recognize that when there is genetic variance in a plant population and selection due to a pathogen (such as a fungus), there will be an evolutionary response and the plant will continue to evolve. Coevolution with pathogens is a major factor in evolutionary change because both the pathogen and the host plant continuously change to avoid the others' defenses. — Preceding unsigned comment added by Stephenoff.2 (talk • contribs) 12:46, 1 October 2014 (UTC) Stephenoff.2 (talk) 20:37, 1 October 2014 (UTC)

Comments

I think that this type of information should definitely be added to the Cell Signaling Project (and Possibly the Molecular Biology Project, too?). There is an entire section in this article that talks about signal transduction, but yet there are no mechanisms or pathways described in details. This should hopefully alert some of us to start looking at information to add. I was considering some pathway in plant immunity to signal the immune response. I think a section of this could be added to the article. . . or should another page be made for this? MChapman5 (talk) 07:07, 28 January 2013 (UTC)

The page signal transduction is redirected from signaling pathway. That article is not specifically about plants. Add it to the article if you want.

You must mean signaling pathway for plants alone. that's interesting. That does seem to deserve its own article. This covers it a tiny bit Plant perception (physiology)#Pathway signals along with other existing articles.Sidelight12 ^Talk 08:11, 28 January 2013 (UTC)

• see Talk:Plant_perception_(physiology)#Pathway signals I brought up this topic on that page about starting a new article on plant pathway signals- Sidelight12 ^Talk 01:25, 30 January 2013 (UTC)

Comments From Caitlin

• The whole article feels more like a paper then an encyclopedia entry, maybe its just me but there seems to be a lot of filler in between facts
  • Cleaned up the filler. MChapman5 (talk) 00:22, 16 April 2013 (UTC)
  • For example the sentence "However, disease control measures are reasonably successful for most crops." in the lead section seems like filler to me
    • Revised the lead section. MChapman5 (talk) 00:22, 16 April 2013 (UTC)
• Maybe more citations in the lead section, R proteins, and in the first paragraph under Plant Immune Systems
  • See comment below. Left lead section uncited. Added citations and cleaned up R proteins. Left first paragraph in immune systems alone because it is also a mini-lead section. MChapman5 (talk) 00:22, 16 April 2013 (UTC)
• Organization is great
  • Thanks for the encouragement. MChapman5 (talk) 04:54, 15 April 2013 (UTC)
• Maybe you could explain more about the roles of E3 signaling → all the bullet points could be expanded upon
  • Added an image to give a visual representation of this. MChapman5 (talk) 00:22, 16 April 2013 (UTC)
• Checked on some of the links to the sources, looks good
  • Thanks for double-checking. MChapman5 (talk) 04:54, 15 April 2013 (UTC)
• Is there anyway to get a picture for Resistance after activation of immune response in the mechanism of action for "Ring and U-box single subunit, HECT, and CRLs", I know its hard to find pictures
  • There aren't really images for these U-box single subunits in action. But you can go to their pages to see their structures, etc. I did add an image to the article, though. MChapman5 (talk) 00:22, 16 April 2013 (UTC)
• The content is really good and overall its a really great article
  • Thanks for your input and advice. MChapman5 (talk) 04:54, 15 April 2013 (UTC)

BreCaitlin (talk) 21:34, 25 March 2013 (UTC)

• For what it's worth, citations aren't necessary in the lead unless there is something special about the content, like a fact that might be controversial. Because the lead should only contain things that are in the article, everything there should already be cited in the body of the article. Biosthmors (talk) 22:30, 2 April 2013 (UTC)
  • Thanks. I'll remember this when editing. MChapman5 (talk) 04:54, 15 April 2013 (UTC)

• Words like "Importantly" (R genes section) and "fascinating" (effector biology section) should be edited to have a more neutral point of view. Also "most active areas in current...research" needs to be more encyclopedic.Biolprof (talk) 22:38, 13 April 2013 (UTC)
  • Sounds good. I'll be sure to remove any of the non-neutral words I see. MChapman5 (talk) 04:54, 15 April 2013 (UTC)

Review from Maximus155

Article summary

• I notice that there are a few opportunities for wikipedia links in the summary. Many of the bolded words could be wiki links, or at least red links to indicate that there should be an article about them, e.g. disease triangle.

wiki-links added.

• Perhaps elaborate more on pre-formed defenses and infection induced responses here.

Done.

• Needs some citations for facts that aren't actually stated in the article, e.g. crop loss due to diseases.

I'm not going to add citations strictly for the fact this is the leading section of the article. However, the crop loss is also outside the scope of my contribution.

Common mechanisms for disease resistance

• I'm sure you were already planning on doing this, but it is a good idea to elaborate on some of these bullets. Not only just giving examples of certain mechanisms, but also explaining how they act to protect the plant.

I am not going to expand on the bullets here because they should be explained farther along in the article under different sections (ex: PTI and ETI, signaling pathways, etc.).

• Wiki links as well as citations would be good for this section

Done.

• Is it typical to utilize piped wiki links as you do? 'Plants' roots release chemicals that attract beneficial bacteria to fight off infections' links to 'Plant use of endophytic fungi in defense' and I'm not sure its appropriate to have large sections of text form a link.

Changed.

Plant immune systems

• it says that plant immunity has a common origin as insects and mammals, I don't think this is true. Multicellularity evolved independently after the plant lineage branched off of the rest of the eukaryotes. If this is true then there needs to be a citation.

Reworded for clarification.

• You say that plant immunity is different than in animals, but then say plants can sense pathogens. That is a little misleading since animals immune systems can detect pathogens as well. I think the point you are trying to make here is that there is a difference in the mechanism that plants use to detect pathogens.

Reworded for clarifiaction.

• In this sections header you say, 'as described below'. I'm not sure that is appropriate wikipedia prose.

Deleted.

• In this sections header you talk about PTIs and ETIs, but the section also includes two other subsections that aren't covered in the header(RNA interference and Defense against whole pathogen species). It would be nice if you could elegantly fit them in as well.

Added sentence for clarification.

• Lots of opportunities again for wiki links

I am not adding wiki-links here because I don't want to overload the page with them. There are plenty of links throughout the subsections of the part of the article. This is merely a "mini" leading section.

PAMP triggered immunity

• You implied earlier that PAMPs and MAMPs were synonyms, but this section seems to indicate that there is a distinction. Could you elaborate?

PAMPS are a subset of MAMPs. MAMPS encompass all microbial patterns, whereas PAMPS are the pathogenic ones.

• Would it be better to include more information about what types of responses are activated in the PTI response

Perhaps in a future contribution, yes.

• Last sentence seems like it is a bridge between the PTI section and the ETI section. It might be more appropriate to put it at the beginning of the ETI section instead, since it indicates the importance of the ETI in catching pathogens that get past the PTI.

I think being a bridge, I will leave it where it is.

• No citations after the first sentence.

Done.

Effector triggered immunity

• This section is much more complete than the PAMP triggered immunity section.

Great to hear!

• 'see below' is probably not necessary.

Deleted.

• What is an effector? Moving the last sentence of the PTI section to the ETI section would fix this.

Effectors are important in PTI because they have to get past this defense. Thus, PTI is first line, which means the effectors evade it. Thus, I think it should still be introduced in the PTI section.

• When you list NB-LLR protein names you finish the list with 'and other acronyms'. If there are too many names to reasonably list, then maybe 'among other names' would be a better way to finish it.

Done.

• Are virulence factors the same as effectors?

They can be, yes.

• Are avirulence genes the same as R genes?

No, Avr genese are created by the pathogens. R genes are by the host plant.

• You later say pathogen avirulence genes, do you mean virulence genes. Virulent means highly infective and I would assume avirulent means the opposite.

No, they are called avirulent genes. It is because they are inactive if the plant combats them, hence the "avirulence."

• I don't know if I would considered plant pathogen interactions to be a signaling pathway. Possibly rephrase that sentence. Look up Red queen hypothesis

Yes, but the way the effectors and genes function are involved in a signaling pathway. This was discussed in my lecture presentation in class.

• It may be important to talk about symbiotic organisms that interact with plants e.g. legumes and nitrogen fixing bacteria or bacteria within the rhizosphere. These organisms need a mechanism(effectors?) to get around the plants defenses. In these cases the organism would not be considered a pathogen.

This would be another contribution, but outside the scope of this assignment for now.

RNA interference

• How does infected cells signaling to uninfected cells improve their resistance? Does it improve or up regulate the RISC pathway? The systemic acquired resistance page doesn't say anything about RISC so the signaling pathway and systemic acquired resistance may not be appropriate for this section.

This section was not my contribution. It is outside the scope of my assignment.

• Are there specific viruses that are affected by RNAi? viruses with dsRNA genomes are obvious targets, but are other types of viruses inhibited by the pathway.

This section was not my contribution. It is outside the scope of my assignment.

• You say it is the result of prior infections, is viral RNA stored within the cell? Does the RNA get transferred in some way to other cells in the plant? Please elaborate on this point.

This section was not my contribution. It is outside the scope of my assignment.

Defense against whole pathogen species

• Is there a term used to describe this suite of defense mechanisms or is it just called 'defense against whole pathogen species?'

This section was not my contribution. It is outside the scope of my assignment.

• You talk about specific genes that are extremely effective against whole species of pathogens. When these genes are knocked out do they lose resistance? If another species is transformed with these genes does it become resistant? The reason I ask is how is it known that these genes alone are responsible for this resistance?

This section was not my contribution. It is outside the scope of my assignment.

• Does inability to colonize a host mean that the host is not habitable for the bacteria? I'm not sure if that would even fall under plant immunity.

This section was not my contribution. It is outside the scope of my assignment.

• Does pre-formed defenses include chemicals that inhibit growth? Plants produce a lot of phytochemicals, many of which may be anti-microbial. I think this may be a good topic to cover.

This section was not my contribution. It is outside the scope of my assignment.

Plant disease resistance signaling mechanisms

• The title of this section is kind of a mouthful :)

Changed.

• You should add a section summary

I think it would be tough to add a summary of the signaling pathways, but maybe a picture or a short list could be added in a future contribution.

Transcription factors and the hormone response

• I feel like the summary could probably be a little more detailed

I did not add a summary to this section because it's bundled as a subset.

• Maybe it should just be the hormone response.

The issue of transcription factors and 24-48 hour pulses are discussed as well.

Mechanism of transcription factors and hormones

• Signaling as a role of ethylene is a little redundant

This is a different mechanism from before.

• It may be better to talk about the roles of plant hormones specifically in terms of plant defense instead of their other roles.

All of the listed roles are involved in signaling pathways for plant defense in one way or another.

Regulation by degradation

• I'm a little confused by what is being degraded. Are you talking about the hormones being degraded or their interacting proteins?

Depends on the hormone. The wiki-link can be used to investigate their page and responses.

Receptor-like kinase

• First sentence is really long. Maybe split it up into two or more sentences

Done.

• How are RLKs activated and regulated by these things? Wouldn't the pathogen itself bind to the RLK and activate it?

No. That is the point of the PAMP. It is only part of the pathogen that interacts with the receptor.

Signaling pathway in innate immunity

• How is this different from the RLK section? I didn't think plants had a robust adaptive immunity besides the RNAi.

RLK is the general mechanism of signaling, but this section discusses the specifics and how/where the RLK act.

Ubiquitin and E3 signaling

• I wouldn't say 'even in plants' since the article is supposed to be about plants.

Deleted.

• Your list could use a little more elaboration.

The list itself is just a summary. Their exact mechanisms can be found in this article elsewhere (ex: PAMP) or through their wiki-links.

Plant breeding and disease resistance

• No citations in this section

This section was not my contribution. It is outside the scope of my assignment.

• You say that diseases can be controlled by pesticides, but didn't you say herbivory was a different thing? Does it prevent insects from allowing infections to occur?

This section was not my contribution. It is outside the scope of my assignment.

• Genetic modification is a good source of plant resistance. You talk about it later but it probably belongs in the list.

This section was not my contribution. It is outside the scope of my assignment.

• You say that there are many exceptions to vertical and horizontal resistance but don't give any.

This section was not my contribution. It is outside the scope of my assignment.

Host range

• citations

This section was not my contribution. It is outside the scope of my assignment.

• It would be nice to have specific examples of horizontal gene transfer and the development of toxins to become pathogenic.

This section was not my contribution. It is outside the scope of my assignment.

Epidemics and population biology

• I like this section, but maybe it should be included in the Plant breeding for disease resistance section.

This section was not my contribution. It is outside the scope of my assignment.

Overall I'm impressed with your work. A little polishing and a little more information is all you need.

Great. Thanks for the help. MChapman5 (talk) 23:59, 28 April 2013 (UTC)

Maximus155 (talk) 21:06, 22 April 2013 (UTC)

Comments from Gpruett2

• Very nice article. Very concise and informative.

Thank you.

• You have a few citation issues that need to be addressed. For instance, the paragraph about effector biology needs a citation. I believe this [1] is the citation that can be used here. Also, it appears that certain paragraphs have an overuse of the same citation. If the citation doesn't change between sentences, then only one citation is necessary and it should be placed at the end of the last sentence that came from that citation. I can help you fix these if you so desire.

I think that citation could work, as well. I did not do the section on effector biology, but when I have some time I will go ahead and go in to change it over to cite the article you present here.

I will go through and eliminate some of the citations. It had been my understanding you should use the citation at the end of every sentence just for complete clarification.

• I notice that there are quite a few lists in the article. Could some of these lists be converted into tables? I ask because some of these lists should be converted to paragraph form and others would benefit from being in a structured table.

I agree these could benefit if they were written in prose. Again, some of the lists are not my own contribution, but when I have some time in the future I can work on this.

• Finally, would it be relevant to talk about genetically modified organisms here? GMOs are sometimes created in order to convey disease resistance so it might be relevant to mention them here.

I think GMOs could make an appearance as a quick subsection. That could make a nice contribution.

Best of luck editing. Gpruett2 (talk) 22:23, 5 May 2013 (UTC)

Thanks for your comments! MChapman5 (talk) 18:56, 6 May 2013 (UTC)

Comments from Flemingrjf

• I noticed no citations in the first paragraph. I am not sure if this was on purpose or not.

This was actually a new contribution just recently made by another editor. The information was in the leading section at first, but I deleted it because I felt it was outside the scope of what the article was about. He instead decided to put it as a "context" section.

• It seems that the pre-formed structures and compounds that contribute resistance prior to immune response should have citations for every one listed. Maybe a paper that talks about each of the uses would be nice.

I agree. This was not my contribution, though. I can still look to try and find sources in the future.

• The first citation seems to be a little weak in that it is not a scientific journal article, but seems to be a blog written by a student.

Agreed. I deleted the citation.

• After reading the effector biology section, I am still not sure what an effector is. That might be a problem on my part for not understanding. I got that it is a protein that goes from the microbe and into the host cell to manipulate the physiology of the host cell. But once that happens, I get lost. Going from the processes of how effectors work to jumping into talking about co-evolution and methods of deriving host functions from effectors maybe should be split into two separate paragraphs. One paragraph talking about their actual function, and the other paragraph addressing the biological significance of effectors.

Effector Biology and the co-evolution were not my contribution.

• The effector paragraph needs citations, as was probably noted.

Yes.

• I noticed that the first ten or so citations did not have direct internet links to the articles. Fixing that would be nice.

I can try and find information on some of them to link the doi.

• I thought it was hard to follow the "Mechanisms of Transcription Factors and Hormones" paragraph. Perhaps defining or clarifying what primary and secondary gene responses are and the crosstalk between them would be good. In addition, transcription pulses are new to me. Clarifying what this is, even if it might seem obvious would be nice.

A primary gene response is a response that activates a first set of genes. A secondary response then activates another additional set of genes that can come about from an activation of the first set. However, I feel like that information should be in an article on genes. Maybe I can find a wiki-link to do this.

• It might be a good touch to have more than one source per section for the first five "Signaling Mechanisms."

I did not add this citation. It was another author's contribution.

• I really enjoyed the ubiquitin and E3 signaling section, which is the one I feel you probably spent the most time on. The citations here were very well done.

Thanks.

• The last three paragraphs have only one citation total. Perhaps if you had extra time to clear this up, that would be good. These paragraphs seem to not be what you focused much of your efforts on, however.

This section was not my contribution.

Thank you for your comments and suggestions! I will try and incorporate them the best I can. MChapman5 (talk) 17:40, 7 May 2013 (UTC)

Flemingrjf (talk) 08:22, 7 May 2013 (UTC)

Comments from Jnims

Great job with your project! There is a ton of information, and most of it looks excellent. Let's start with the things I particularly enjoyed/appreciated:

Good stuff

• Organization: good split between bullet points and informative paragraphs, which makes the reader's task easier
• Good distribution/number of sources
• Clear prose
• Very informative

Thanks for editing.

And here are some suggestions for improvement:

Suggested improvments

Intro/Lead

• The opening paragraph is rather text-heavy, and could be improved by dividing it into a few smaller paragraphs, for ease of reading. Also, should the other terms ("disease triangle," etc.) be bolded, or just the article title?

Corrected. Thanks.

Context

• Although I love the content of the "Context" section, I think the title could be improved. Perhaps "Importance" or "Relevance?" I also considered "Background," but I think that's slightly different

I agree. This was not my contribution but I will fix the name.

• The wording of the following sentence is confusing: "Plant disease resistance is crucial to the reliable production of food, and it provides significant reductions in agricultural use of land, water, fuel and other inputs." Do you mean that the disease resistance is bad for agriculture? I would have thought the opposite was the case (i.e., disease resistance making agriculture more successful).

This was not my contribution, but good point.

• This sentence needs a citation: "Across large regions and many crop species, it is estimated that diseases typically reduce plant yields by 10% every year in more developed settings, but yield loss to diseases often exceeds 20% in less developed settings."

Agreed.

Common mechanisms

• An introductory sentence or two would be helpful.

Yes. However, this was not my contribution.

• More in-text links would also be helpful

Done.

• More sources would also be appreciated

Agreed.

Plant immune systems

• The relevance to disease resistance of the section "Mechanisms of transcription factors and hormones" is somewhat unclear, and could be improved with a sentence or two that specifically mentions how the hormones you listed contribute to resistance, rather than signal transduction in general.

Good point. I can try and clarify this in a future contribution.

• You say "[a] majority of the plant's gene expression in the immunological response is regulated by degradation", but the section ("Regulation by degradation") is quite small. Could you add a little more information, or incorporate the E3 section into it?

I am sure there is more information on degradation. Hopefully in future contributions, the information could be added here.

Best of luck! Jnims (talk) 19:53, 8 May 2013 (UTC)

Thanks for the edits and suggestions! MChapman5 (talk) 20:41, 8 May 2013 (UTC)

Student edit submission for review

I am a student in the Advanced molecular biology PCB5595 class with Dr. Bass. Please review the following suggested edits. Kaurbrar (talk) 18:19, 7 December 2017 (UTC)

• Salicylic acid- Salicylic acid triggers defense mechanism in plants in response to various environmental factors such as light, temperature, drought and microbial attacks. SA signaling pathway functions by interacting with components of other input pathways involved in plant defense. SA application establishes local and systematic acquired resistance in plants and leads to accumulation of pathogenesis-related (PR) proteins. The treatment of seeds with SA inhibit germination due to an SA-induced oxidative stress
• Jasmonic acid- Jasmonic acid induce SAR (systemic acquired resistance) in plants against abiotic and biotic stress, mainly insects and few pathogens. Once synthesized, JA is transported to unwounded cells, where it activates protease inhibitor genes, thus reducing digestibility of plant tissues. ROS, Calcium ion influx, MAP kinase cascade, and Nitric oxide play an important role in the JA signaling transduction pathway. JA associated rapid defense response in plants is activated by electrical signaling. Jasmonic acid is available commercially for treating seeds and spraying young plants to control pest damage.
• Ethylene - Ethylene is a gaseous phytohormone that activates defense mechanism against pathogens such as fungi and bacteria. It initiates programmed cell death (PCD), in response to invading plant pathogens.

References

Rewiring plant defence genes

Can this be mentioned:

• Rewiring plant defence genes to reduce crop waste link 1
• Rewiring plant defence genes to reduce crop waste link 2
• Bacteria Use Plant Defense For Genetic Modification

Genetics4good (talk) 10:26, 24 August 2018 (UTC)

Wiki Education assignment: Plant Behavior 2022

This article was the subject of a Wiki Education Foundation-supported course assignment, between 28 March 2022 and 17 June 2022. Further details are available on the course page. Student editor(s): Jchang08 (article contribs).

— Assignment last updated by Gonet99 (talk) 19:16, 13 June 2022 (UTC)

Wiki Education assignment: Plant Ecology Winter 2023

This article was the subject of a Wiki Education Foundation-supported course assignment, between 16 January 2023 and 10 April 2023. Further details are available on the course page. Student editor(s): C-ferns1202 (article contribs).

— Assignment last updated by C-ferns1202 (talk) 17:20, 15 February 2023 (UTC)