Dark Heart Nursery Identifies Cannabis Pathogen, Hop Latent Viroid (dudding)

Lithium

Lithium

Lithium•Iron•Boron
Found this to be semi-interesting. Sorry if posted elsewhere.

Dark Heart Nursery Identifies New Pathogen, Creates Patent-Pending Process for Testing and Eliminating Cannabis “Dudding”

From link:

OAKLAND, Calif.--(BUSINESS WIRE)--Dark Heart Nursery (DHN) proudly announces that it is the first organization to positively identify hop latent viroid (HpLVd) as the cause of “dudding” in cannabis. Since 2018, DHN has also been successfully testing for and eliminating HpLVd through a patent-pending clean plant process.

On the heels of this groundbreaking completed research, the company has also announced that project lead Dr. Jeremy Warren has officially joined DHN as Director of Plant Health.

“The positive identification of the HpLVd pathogen and our patent-pending clean plant process to test for and eliminate it represent a significant advance towards keeping cannabis crops healthy and supporting long-term business growth for cultivators,” said Dan Grace, Founder and President of Dark Heart Nursery. “With Dr. Warren at the helm, we are incredibly excited to now offer diagnostic and curative services for HpLVd to licensed cannabis businesses in California, as well as continue our research in identifying and eradicating additional cannabis-infecting pathogens.”

“Dudding” is a colloquial name for a variety of symptoms, which include loss of vigor, stunting, reduction in yield, reduction in potency and changes in morphology. The syndrome was codified in 2017 by Dr. Rick Crum who first coined the phrase “Putative Cannabis Infectious Agent” (PCIA) to describe it. In 2015, Dr. Crum reported that as many as 35 percent of observed plants showed PCIA symptoms.

In 2017, Dark Heart Nursery began working with Dr. Warren to determine the cause of PCIA. Symptomatic and asymptomatic plants were collected, and next generation RNA sequencing was performed to determine a probable cause of the disease. After analysis of the results in November 2017, it was determined that Hop latent viroid (HpLVd) was the most likely candidate pathogen. A genetic test was then developed to aid in differentiating healthy plants from infected plants.

“It is important to note that finding a potential pathogen within a plant was only the first step in determining if the pathogen is indeed causing the disease in question,” said Dr. Warren. “To demonstrate causality, healthy plants were inoculated with an infectious clone of HpLVd to confirm that the developed symptoms were consistent with PCIA. Our team monitored these infected plants, as well as controlled (healthy) plants for three months to track symptom development. After this time, it was apparent that the HpLVd-infected plants were showing symptoms consistent with PCIA, such as yellowing of leaves, malformed leaves and stunted growth. These results confirmed that HpLVd is causing PCIA symptoms in cannabis.”

In 2014, DHN established the cannabis industry’s first tissue culture laboratory. Among other areas of research, this lab has focused on the development of clean plant protocols through which cannabis can be cured of pathogens and cataloged for later use. Under the leadership of Research Manager Will Roberts, the company developed a patent-pending clean process, which is capable of reliably eliminating HpLVd from infected specimens. For the last year, Dr. Warren’s discovery and subsequent diagnostic tests have allowed DHN’s lab team to reliably and demonstrably eliminate HpLVd. To date, 31 varietals have been cured of the disease.
Click to expand...

Hop latent viroid (HpLVd) was first characterized in Humulus lupulus (hop) plants (Putcha et al. 1988). The initial research suggested it was a minor pathogen in hops; however, recent research has shown that infection with HpLVd can have a significant impact on yields and secondary metabolite production (Adams et al. 1991, Barbara et al. 1990, Matoušek 1994). These yield and metabolite impacts seem to be even more pronounced in cannabis. If plants are showing symptoms of HpLVd infection, there are a few actions to consider. Always remove infected plants from the growing area to prevent spread. HpLVd, like many viroids, has been shown to be primarily mechanically transmitted, so strong nursery sanitation protocols are necessary when pruning and processing plants. The secondary means of HpLVd transmission are not yet fully understood. However, other viroids in the Cocadviroid genus have been shown to be pollen and seed transmissible. This suggests that HpLVd may also be transmitted in a similar manner, but further study is required. Insect transmission of viroids is also still being studied. Cannabis plants can be carriers for HpLVd without showing any outward symptoms of the disease. For this reason, it is important to test all the plants in a mother block for HpLVd infection and to purchase clean plant materials whenever possible. Although the company’s work did not include any hemp varietals, it is highly likely that HpLVd also impacts that crop.
Click to expand...


Nice to see they've identified the pathogen they've spread to hundreds/thousands of gardens. And patented the "cure". :hmm::hmm::hmm:

Thoughts?
 
“Nice to see they've identified the pathogen they've spread to hundreds/thousands of gardens. And patented the "cure". “
LoL. And all the growers who were dudded out quit growing and got a restraunt job because no one until now had a cure for the duds.
Imo there was pathogen duds and the microscopic worm duds that cap had. I had the pathogen duds where sometimes single branches would dud sometimes The whole plant. I beat it with a $10 bottle of physan20 and a bottle of physan35.
 
Annaba said:
Well, always bein skeptical of this kinda stuff, 3 main things come to mind...#1, they claim it's contagious, yet I've never heard any grower that has experienced "duddin" to ever claim it spread to other plants. #2, I have heard numerous reports of folks simply placing a "duddin" plant outside for a spell, to allow it to flush out to better health, an I've never heard anyone report the issue returned...which does not coincide with their claims at all. An finally, #3, I know quite a few large scale hops farmers, an I'm not sayin this virus doesn't exist, but for a hops virus to be so much more common in cannabis than it is in hops, seems a lil unrealistic, IMO. I know I've never heard mention of it, an I actually grow em on a small scale...nothin like the farms I speak of, but enough to where if it were at all common, I was have at least heard of it...but I could be wrong, jus my initial thoughts.

With that bein said, we live in a world where very few read the actual story, but will argue tooth an nail bout what they believe the story was bout from the headline alone.
In other words, they'll likely make a lot of money from their claims, rather they're true or not.
Click to expand...

The dud is certainly a thing, at least 2 very erudite academics on the subject of cannabis have observed it. I received dudded plants twice, they both spread and wiped out my garden. The symptoms were the same--slow growth, limp and weak branching...the dried finished product had no crystals. Took quite a while to rectify the situation. I certainly don't know what it was, or if the malady presented in the article was it.

Putting my plants outside and flushing them did nothing for me. I tried everything for the sake of my livelihood.

180 said:
Thanks Li. I didn't see anything about who/how the pathogen was spread? How is it that you blame them for spreading it around?
Click to expand...

Several reports across the boards during the height of the panic, and more even up til last year. Most recently I recall a well-known breeder posting a very bad looking cut with the telltale symptoms on Instagram, cut came from DHN. You can find reports at all the larger cannabis forums.

And you can imagine, if the article is true, that any clone distributor would have passed plenty of infected cuts if no proper identification existed until very recently.

Variety said:
“Nice to see they've identified the pathogen they've spread to hundreds/thousands of gardens. And patented the "cure". “
LoL. And all the growers who were dudded out quit growing and got a restraunt job because no one until now had a cure for the duds.
Imo there was pathogen duds and the microscopic worm duds that cap had. I had the pathogen duds where sometimes single branches would dud sometimes The whole plant. I beat it with a $10 bottle of physan20 and a bottle of physan35.
Click to expand...

Certainly could have been multiple vectors or different maladies that represented themselves as a dud to the community.

I wish getting rid of it was that easy for me. I had to lose all my stock and buy all new grow gear. Not going to name anyone but the person I got it from the first time went through the same thing.

Aspirin, sunlight, physan20...I wish any of these would have worked. Never tried chitosan though...
 
Some more info on HLV. It showed up in my garden but only on one plant and not in every grow. First showed up about three years or so ago, then disappeared, only to reappear last year. It has only affected the Genius, but I don't think that's what it came in on, as I have had the Genius for 20 years without any problems until recently. I have adopted a sanitation protocol when cloning to prevent it spreading. Sporadic; I hope it doesn't show up again...

"Hop Latent Viroid Information
Matthew Gates

The Hop Latent Viroid (HpLV) is a viroid in the genus Cocadviroid, of family Pospiviroidae, which are known to infect the nucleus of plant cells. Hop Latent Viroid can infect both Humulus and its sister genus Cannabis. In Cannabis as well as Hops, both of which diverged from a common ancestor 18 million years ago, HpLV can colonize asymptomatically, but often causes brittle stems, a horizontal growth pattern, and stunted growth, with the viroid transmitting through mechanical touch with plants or equipment. Conventional treatment of the viroid is not possible at the time of this writing, but like with other plant pathogens a combination of thermotherapy and tissue culturing can be an effective treatment but the process is expensive and not easily available. Preventative action through vigilant hygienic procedures in cleaning tools and materials in contact with Cannabis crops, as well as the quarantining of new plants to check for symptoms are both biosecurity best practices. Regular testing of crop plants and quarantine plants can be useful to identify potentially asymptomatic populations. Currently, virus and viroid research has become much more possible and accessible with the advent of genomic technology. However, there is little research yet on the interaction between Cannabis and HpLV.
While viruses typically have a protective protein coating, viroids encode no proteins, existing as strands of RNA molecules that infect, replicate, and become released by plant cells, propagating mechanically through infected tissue contact, including the reproductive tissues of pollen and ovules. Viroids are some of the smallest and simplest replicating molecules, and were discovered very recently in the early 1970s. Because of their recent discovery, much of their pathology is still not understood.
Less than two decades later, Hop Latent Viroid was first identified in the Kingdom of Spain in 1987 and Federal Republic of Germany in 1988. It was later detected in the United Kingdom in 1990 and as of 2003, has been detected at extremely high levels in the territories of Portugal, Spain, France, Belgium, the Czech Republic, Hungary, the Poland, Serbia, and the Russian Federation. Cannabis populations in these areas may be threatened by the presence of Hop Latent Viroid, including the USA. Hop Latent Viroid was first documented on Cannabis in 2018 in Southern California, but symptomatic plants have been observed existing in various cultivation spaces and nursery stock for several years before. Hop Latent Viroid has been detected in 80 cultivars in 19 countries across 4 continents. Hops have been cultivated commercially in western North America in California, Oregon, and Washington since the 1900s, with Hops production increasing after 1933, but declining sharply by the 1990s in California. Several agricultural zones in California still cultivate Hops and have become more popular recently totaling close to 80 acres according to the California Hop Growers Association in 2017. As biosecurity standards are established, implemented, and improved upon globally, Hop Latent Viroid incidences may decrease commercially especially with the advent of easier pathogen testing, though viroids generally have great potentiality to spread through vegetative propagation particularly since they may be asymptomatic for some period of time, hence the "latent" in Hops Latent Viroid."
 
great one more thing the Noobs will scream out in a thread.... IS THIS THE DREADED PATHOGEN????????


i can the hundreds of threads being posted now.......

like Has Anyone Ever Used Tap Water to Water Their Plants????
 
Well, despite the fact that dudding has been with us for a good ten years, the news about HLV hasn't spread far. Most growers are clueless about it. I'm glad it hasn't been a big thing here; in the PNW it seemed like it hit everyone.

Noobs will be noobs. Forever Clueless. What's saddest are the ones who still grow like noobs, many years on. I had a neighbor like that. I avoided smoking his weed.
 
I find this interesting and a little worrying because Dark Heart Nursery is the outfit that sold the clones I'm just starting to grow out right now. I see that this article was from March 2019 or so... you guys don't think they would still be selling clones with this "dudding" disease a year and a half later, do you? Suddenly I'm wondering whether I should scrap it.
 
Reverend Budbreath said:
I find this interesting and a little worrying because Dark Heart Nursery is the outfit that sold the clones I'm just starting to grow out right now. I see that this article was from March 2019 or so... you guys don't think they would still be selling clones with this "dudding" disease a year and a half later, do you? Suddenly I'm wondering whether I should scrap it.
Click to expand...

Hello RB it’s pretty easy to spot out a dudded cannabis plant, dark green serrated small fan leaves that have a twist to them. If you post a picture I can tell ya if it’s dudded or not. I have dealt with them many times.
 
Variety said:
Hello RB it’s pretty easy to spot out a dudded cannabis plant, dark green serrated small fan leaves that have a twist to them. If you post a picture I can tell ya if it’s dudded or not. I have dealt with them many times.
Click to expand...

Thanks bud, they look normal... I'd never heard of this disease until today when I read the post. I thought maybe it was an insidious thing that remained invisible until the worst possible time (flowering) and then emerged. So I guess you're saying it would be very apparent in vegging clones? I just bought these clones like 4 or 5 days ago and popped them into soil to start them up.

One thing I noticed was when the dispensary sold me the clones, they had been sprayed with something off-white or beige and heavy, and I thought "okay, that's something protective against PM and bugs, it'll wash off" but it kind of stained the leaves and doesn't come off, so I wonder what they sprayed and now wonder too whether it is something to do with the dudding disease. Probably not...

EDIT: So I just spent the last half hour researching this "Hop Latent Viroid," and apparently photos of symptoms in veg are very rare. I didn't find any. Do you have photos you could share that show what it looks like in a plant in veg? This sounds dreadful, and there are people saying in YouTube comments that it's in 95% of the weed in California dispensaries (still) and that there hasn't been any "real dank" in the state in a very long time (I sure haven't seen much). That struck a nerve, because that aligns with a major reason I'm getting back into growing, which is that—retail prices aside—I can't find anything in dispensaries that is anywhere near as good and fresh as it should be. It always seems mostly depleted of terpenes and weak on trichomes. And now I learn that there was/is a rampant plant disease that decreases terpene and trichome production. Hmmm.
 
Last edited:
Oh hey, my houseplants do just fine with tap water, what the heck is wrong with good tap water? signed: NoobyMouse
 
I use tap water but let it sit for at least 24 hours before doing so.
Where I live the water comes from the mountains and isn't over treated.
 
Variety said:
Hello RB it’s pretty easy to spot out a dudded cannabis plant, dark green serrated small fan leaves that have a twist to them. If you post a picture I can tell ya if it’s dudded or not. I have dealt with them many times.
Click to expand...

Hey Variety, I think I will take you up on this because when I checked on them today, lo and behold one of them is showing a weird distortion of a leaf blade that wasn't there at all a day or two ago. What do you think?
 

Attachments

  • Strawnana-suspect-looking-leaf.png
    Strawnana-suspect-looking-leaf.png
    979.8 KB · Views: 13
Reverend Budbreath said:
Hey Variety, I think I will take you up on this because when I checked on them today, lo and behold one of them is showing a weird distortion of a leaf blade that wasn't there at all a day or two ago. What do you think?
Click to expand...

Hello RBB I think ya should just give her time. Looks like you just potted her up and maybe a little stressed. That little hook and verigation is maybe from the stress or a ph issue A d maybe just over watered if you just potted it up.
I have strains that variegate that have been tested and came back negative for a viroid. Does not spread to other plants.
I did see someone a couple years ago in Oregon I think that did have the tmv virus and the variation spread to every plant. Never seen anything like it.
Imo your plant will be fine once she starts growing again.
 
Thanks Variety. I'd say it's definitely stress then because these clones were in rockwool and I put them in soil. That always seems to be a tortuous few days of adjustment whenever that's the situation.

Well if you don't think that's a diseased clone, I have a real dilemma here because after reading about HLV, and knowing my clones are from Dark Heart Nursery, I hestitate to keep them because if there is even a 5% chance that the disease could show up later in flowering, I'd rather toss them now and start over from seed (which is my preferred method anyway). I'd be really pissed if that happened because I have a chance right now to avoid it. I saw a comment on YouTube where a guy said "it's in 95% of the clones and weed in California dispensaries." That makes me nervous. One of the main reasons I'm starting to grow again is to get the freshness and the trichs and the terpenes... if I grow something that is lacking those due to a disease, it would be a stupid waste of time and energy for three months. And now they're rooting and about to take off in the soil. Tough choice...
 
Reverend Budbreath said:
Thanks Variety. I'd say it's definitely stress then because these clones were in rockwool and I put them in soil. That always seems to be a tortuous few days of adjustment whenever that's the situation.

Well if you don't think that's a diseased clone, I have a real dilemma here because after reading about HLV, and knowing my clones are from Dark Heart Nursery, I hestitate to keep them because if there is even a 5% chance that the disease could show up later in flowering, I'd rather toss them now and start over from seed (which is my preferred method anyway). I'd be really pissed if that happened because I have a chance right now to avoid it. I saw a comment on YouTube where a guy said "it's in 95% of the clones and weed in California dispensaries." That makes me nervous. One of the main reasons I'm starting to grow again is to get the freshness and the trichs and the terpenes... if I grow something that is lacking those due to a disease, it would be a stupid waste of time and energy for three months. And now they're rooting and about to take off in the soil. Tough choice...
Click to expand...
I certainly don’t want to be the one to tell you to grow them then it back fire because I’m not there with the plant. But if you want to play it safe and you would rather pop some seeds anyway that might be your best bet. It’s a hard decision lol and I’ve gone both ways on it and sometimes I regretted it and sometimes it’s like hey it worked out!
 
Variety said:
I certainly don’t want to be the one to tell you to grow them then it back fire because I’m not there with the plant. But if you want to play it safe and you would rather pop some seeds anyway that might be your best bet. It’s a hard decision lol and I’ve gone both ways on it and sometimes I regretted it and sometimes it’s like hey it worked out!
Click to expand...

I hate pulling the plug when I don't have a real good reason... this seems like a good reason but it's still tough. I think I'm going to go ahead with them, but GOT DANG IT, if they go south I'm gonna be pissed!! :gramps::mad: Thanks again for the counsel.
 
Last edited:
Reverend Budbreath said:
I hate pulling the plug when I don't have a real good reason... this seems like a good reason but it's still tough. I think I'm going to go ahead with them, but GOT DANG IT, if they go south I'm gonna be pissed!! :gramps::mad: Thanks again for the counsel.
Click to expand...

I always say take what you read on the internet with a grain of salt, but if your gut feeling says grow them out I’d grow them out. If you think they are looking wired in a week or two post some more picks and I’ll try to help.
 
You must log in or register to reply here.
Back
Top