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Dud Identification Collective Knowledge.
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Overview of Witches' Broom in plants, and the various causes, including phytoplasma, from Missouri Botanical Garden:
Witches' Broom
Plants in the genus Celtis (hackberries), which is in the Cannabaceae, are notable for their tendency to get Witches' Broom, and it has always been said that it was caused by a gall mite. Here is a quote from the MBG article above about that:
But you will notice in the literature that a lot of plants that were thought to have WB from gall mites really have phytoplasma:
They confirmed this with a two kinds of special PCR:
It requires specialized PCR to detect it:
Above quotes from:
Genetic Characterization and Classification of Two Phytoplasmas Associated with Spartium Witches'-Broom Disease
Witches' Broom
Plants in the genus Celtis (hackberries), which is in the Cannabaceae, are notable for their tendency to get Witches' Broom, and it has always been said that it was caused by a gall mite. Here is a quote from the MBG article above about that:
Missouri Botanical Gardens said:
But you will notice in the literature that a lot of plants that were thought to have WB from gall mites really have phytoplasma:
They confirmed this with a two kinds of special PCR:
It requires specialized PCR to detect it:
Above quotes from:
Genetic Characterization and Classification of Two Phytoplasmas Associated with Spartium Witches'-Broom Disease
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I know aphids aren't listed as a vector in any of these articles, but they are often passive phloem feeders... where phytoplasmas are found. Maybe aphids have too short of a life cycle for a sufficient incubation of the phytoplasmas.
Could hundreds of aphids be enough?
In this study they found phytoplasmas inside of aphids living on an infected tree.
http://books.google.com/books?id=YtEpeu_7u8YC&pg=PA258&lpg=PA258&dq=phytoplasma+aphid&source=bl&ots=EUi8Zb5ANr&sig=7TxRLKoS-4QhgiXN5n2HgSxB_2s&hl=en&sa=X&ei=zlSWU8DhBsTyoATgp4HoCw&ved=0CE0Q6AEwCA#v=onepage&q=phytoplasma%20aphid&f=false
"'Ca. Phytoplasma mali' was also detected by molecular means in different aphids species captured on infected trees (Cainelli et al., 2007). Unsuccessful transmission trials and low concentrations of the phytoplasma measured by quantitative PCR in the aphids indicate that aphids are not able to transmit AP."
Could hundreds of aphids be enough?
In this study they found phytoplasmas inside of aphids living on an infected tree.
http://books.google.com/books?id=YtEpeu_7u8YC&pg=PA258&lpg=PA258&dq=phytoplasma+aphid&source=bl&ots=EUi8Zb5ANr&sig=7TxRLKoS-4QhgiXN5n2HgSxB_2s&hl=en&sa=X&ei=zlSWU8DhBsTyoATgp4HoCw&ved=0CE0Q6AEwCA#v=onepage&q=phytoplasma%20aphid&f=false
"'Ca. Phytoplasma mali' was also detected by molecular means in different aphids species captured on infected trees (Cainelli et al., 2007). Unsuccessful transmission trials and low concentrations of the phytoplasma measured by quantitative PCR in the aphids indicate that aphids are not able to transmit AP."
http://biomedfrontiers.org/infection-2013-11-39/
Role of gibberellic acid in tomato defense against potato purple top phytoplasma infection
Abstract:
Infection of tomato by potato purple top (PPT) phytoplasma causes disruption of gibberellin (GA) homeostasis in the plant host. Such pathologically-induced GA deficiency can be partially reversed by exogenous application of GA. The present study was designed to explore the role of GA in tomato defense response against phytoplasmal disease, and to determine whether pretreatment with GA would protect healthy tomato seedlings from subsequent phytoplasmal infection and disease development. Our results revealed that, following exogenous GA application and subsequent PPT phytoplasma graft inoculation, there was an apparently coordinated down-regulation of the gene encoding a key GA signaling component and growth repressor known as DELLA protein (GAI) and up-regulation of genes involved in salicylic acid (SA) synthesis (ICS1), signaling(NIM1), and downstream defense responses(PRP-1). Our results also indicated that differential regulation of the above genes was correlated with an increase in activities of defense-related enzymes β-1,3-glucanase (GLU) and chitinase (CHI). The data presented in this communication provide evidence to suggest that GA may act via DELLA and SA signaling pathways to modulate host defense in response to PPT phytoplasma infection. Although the GA pretreatment-induced defense was not sufficient to prevent a systemic infection, it reduced phytoplasma titer and significantly attenuated disease symptoms. While the actual molecular mechanism underlying the GA-induced plant defense remains elusive, findings from the current study open new opportunities for in-depth studies of the functional role of the GA signaling network during defense response against phytoplasmal infection.
Role of gibberellic acid in tomato defense against potato purple top phytoplasma infection
Abstract:
Infection of tomato by potato purple top (PPT) phytoplasma causes disruption of gibberellin (GA) homeostasis in the plant host. Such pathologically-induced GA deficiency can be partially reversed by exogenous application of GA. The present study was designed to explore the role of GA in tomato defense response against phytoplasmal disease, and to determine whether pretreatment with GA would protect healthy tomato seedlings from subsequent phytoplasmal infection and disease development. Our results revealed that, following exogenous GA application and subsequent PPT phytoplasma graft inoculation, there was an apparently coordinated down-regulation of the gene encoding a key GA signaling component and growth repressor known as DELLA protein (GAI) and up-regulation of genes involved in salicylic acid (SA) synthesis (ICS1), signaling(NIM1), and downstream defense responses(PRP-1). Our results also indicated that differential regulation of the above genes was correlated with an increase in activities of defense-related enzymes β-1,3-glucanase (GLU) and chitinase (CHI). The data presented in this communication provide evidence to suggest that GA may act via DELLA and SA signaling pathways to modulate host defense in response to PPT phytoplasma infection. Although the GA pretreatment-induced defense was not sufficient to prevent a systemic infection, it reduced phytoplasma titer and significantly attenuated disease symptoms. While the actual molecular mechanism underlying the GA-induced plant defense remains elusive, findings from the current study open new opportunities for in-depth studies of the functional role of the GA signaling network during defense response against phytoplasmal infection.
So according to that slide show/lecture, phytoplasmas cannot be mechanically transferred. Meaning I could rub an infected stem of one plant all over a healthy clean clone and nothing would come of it. Using the same razor wouldn't transfer the phytoplasmas either.
I figure infected mothers make infected clones... but how is it spreading to different varieties so well without leafhopper populations?
What say you Storm Shadow? You're confident that the AYp is a primary cause for many peoples' duds, so how is it being transferred?
The Aster Leafhopper is ~4mm long, more than 4x larger than an adult spider mite, so I don't think we're all missing these bugs.
I figure infected mothers make infected clones... but how is it spreading to different varieties so well without leafhopper populations?
What say you Storm Shadow? You're confident that the AYp is a primary cause for many peoples' duds, so how is it being transferred?
The Aster Leafhopper is ~4mm long, more than 4x larger than an adult spider mite, so I don't think we're all missing these bugs.
Eriophyid mites ... Those aren't Cyclamen Mite Eggs everyone thinks they are seeing... the nice smooth round ones...
It would only take one leafhopper, one time, to make that cut in someones garden become a phyoplasma factory, if it was used as a mother, well there you go. How many plants in a room could be infected by ONE leafhopper or Psyllid, in one day? Could you find a single hopper in one of your rooms?
If Eriophyid mites can spread Phytoplasma in Roses and cause RRV... If they bite into a plant with AYP.. who says it cant be spread?
What else can cause a plant to have witches broom? Its only a few possibilities and once you narrow it down... it becomes pretty obvious whats going on... again... it takes a couple of years of seeing this shit to really understand all of the symptoms...
What else can cause a plant to have witches broom? Its only a few possibilities and once you narrow it down... it becomes pretty obvious whats going on... again... it takes a couple of years of seeing this shit to really understand all of the symptoms...
I have seen leaf hoppers in Warehouses b4 out here in SoCal... to be honest... I didn't see ever more then one at a time and thought they were just harmless insect that flew into my room... Id see no symptoms of any damage so I never thought twice about them...
Hmm, I don't know. Mites were postulated as vectors of phytoplasma in some WB situations, but recent evidence points to these examples as being caused by a virus vectored by a gall mite.
If you go by the book, the thing about gall mites not having access to the phloem, and the fact that leafhoppers etc are "true alternate hosts" that are in a kind symbiosis with the phytoplasma, rules out mites. But, the book is still being written, so we will see. There seems to be a great deal of research activity on this front these days, so I think the answers are forthcoming.
This is one of the cases I was talking about. Rose Rosette has been shown to be a virus, not phytoplasma.
That's a good thought. You can't proceed correctly with a strategy of eliminating candidate causes, unless you know all of them.I think there are quite a few, really. Maybe we should make a list?
G`day Storm Shadow
Although you have posted lots of informative articles .
Do you think that Witches Broom is what is effecting the plants ? I see no evidence of Witches Broom in the pix of duds people have posted . Low vigour yes . Less than fully formed trichs yes . But Witches Broom . Symptoms . No .
So far you have linked us to lots of info re plant pathogens . Not one that actually is related to Cannabis ...
Sam keeps tellin you guys get the plants to a lab , find out what it actually is . Then no need to read 50 PDF`s about things that may not even be the cause . And or treatments for bugs / pathogens that you can`t identify .
Some of the links were quite informative . Prolly quite useful if thats the specific crop you are growing . Other wise not relevant .
Thanks for sharin
EB .
Although you have posted lots of informative articles .
Do you think that Witches Broom is what is effecting the plants ? I see no evidence of Witches Broom in the pix of duds people have posted . Low vigour yes . Less than fully formed trichs yes . But Witches Broom . Symptoms . No .
So far you have linked us to lots of info re plant pathogens . Not one that actually is related to Cannabis ...
Sam keeps tellin you guys get the plants to a lab , find out what it actually is . Then no need to read 50 PDF`s about things that may not even be the cause . And or treatments for bugs / pathogens that you can`t identify .
Some of the links were quite informative . Prolly quite useful if thats the specific crop you are growing . Other wise not relevant .
Thanks for sharin
EB .
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I contend that the cumulative information being gathered here as valuable. even when a speculative candidate for the cause proves incorrect it is a highly valuable accomplishment in the process. like ss stated when you narrow it down and compare it to the possible known pathogens and pests the research disproving them only brings us closer by eliminating a wrong answer which lessens the ammount of tail chasing. i am all for full tilt headlong exploration into any research of potential cause.this crowdsource collective research is quickening the pace making one dead end go faster than a year of spare time research by one member. its may be bro reviewed bro science but it is apparently all we have at the moment until someone sources a lab able to run pcr tests. the body of research is daunting and with us all critiquing each others ideas we will get there. i dont feel we can rule out phytoplasma just yet, as stated its an emerging field of research that is currently finding new data all the time. if it can spread by vector it may prove that there are more vectors than have been discovered. time will tell. lets keep it civil and examine each others ideas respectfully but with a constant eye out for holes in theories. this is one of the best threads going imo. thanks everyone.
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What I have been saying all along. Lot's of turbo-posting, lots of speculation. Zero science. Only a laboratory assay can prove speculative theories, and obviously, from pictures posted here and elsewhere, there are multiple issues being lumped together as if it were a single problem with a single cause. There is no single cause of duds, and what people are calling "duds" are different things, with different causes. In the case of sour dubb and it's crosses, there is a genetic component, a recessive trait that rears it's ugly head at times. We know that broad & cyclamen mites cause duds, but they are not vectors of phytoplasma, and neither are fungus gnats.
I have grown a number of duds... and only seen a crazy witches broom in a few times... but once you see it.. You'll never forget it... and there still hasn't been nearly enough pics of duds put up yet....
If you are familiar with a certain strain you've grown for years... after time of it being infected you slowly notice symptoms...some are only in Veg...others in flower..
Again if you haven't had this problem b4.. saying "YOU' cant see it... is pointless
If you are familiar with a certain strain you've grown for years... after time of it being infected you slowly notice symptoms...some are only in Veg...others in flower..
Again if you haven't had this problem b4.. saying "YOU' cant see it... is pointless
Retro has never grown Sour Dub or even been to Progressive Options... so you can pretty much write off his opinion on the entire subject of any of these 2 topics
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