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Aloha everyone!

Many members have had times when their plants don't seem to be responding adequetly. Perhaps it is an imbalance in pH and nutrients. Or pests and fungi. While not as prevalent for me (I do not touch outside clones), it has been coming into my view for awhile now. Confirming with my braddahs in Cali and Oregon, it's happening more than you think, with elite clones here on the West Coast. This situation appears to be endemic to parts of EU as well.

"Over time, however, growers may notice changes in their grows: stunted growth, smaller flowers, yellowed leaves, limited cannabinoid and terpene production. Is this phenomenon – commonly referred to as ‘dudding’ – the sign of overstressed plants or the harbinger of something much worse?"

These days, it would be prudent to be wary of clones having something you can't see, and quarantining plants before introduction into your space.
Or better yet, starting with fresh seed every season.
Anyway, here's a few articles I thought might add to the conversation.

2 years ago:
"These unusual symptoms were recorded in 2015, when Dr. Rick Crum found that as much as 35 percent of nursery samples demonstrated these symptoms, along with stunted growth. At the time, the cause of these symptoms was identified as “punitive cannabis infective agent” (PCIA), a term used to describe the unexplainable loss of vitality among cannabis plants."

6 months ago:
"We knew that because lost vigor was appearing in asexually multiplied serial cuttings the problem could not be explained by “genetic drift,” which is a shift in the frequency of genes within a small sexually reproducing population. Growers wondered what the causes might be, and even addressed the possibility that simply making serial cuttings might result in diminished vigor."

"Unsanitary cuttings are the main root of Cannabis diseases, and rather than trying to clean an infected clone, growers can simply sow seeds. Seed and pollen transmissions of viruses and viroids have been shown for several crops but are unconfirmed in Cannabis. Traditional seed propagation interrupts a pathogen’s life cycle, allowing a fresh start each year. Seeds provide the best chance of procuring clean plants and establishing a new clone. Who knows? You might even discover the next OG Kush!"

"As cannabis is increasingly commercialized, disease control will become the responsibility of licensed and certified nurseries that will preserve and distribute clean stock, like all clonally based commercial agriculture from potatoes to berries."

"Hop Latent Viroid (HLVd) is one of the biggest threats to the cannabis industry. The disease is difficult to identify and can rapidly spread undetected throughout a facility. According to MJBizDaily, California operators have lost 10-30% of their crop from the disease, and internal data shows infected plants can also suffer up to a 35% loss in cannabinoid content such as THC, and up to 70% reduction in yield."

there’s a video on YouTube somewhere with SB and he goes to the flowery fields clone nursery in Vienna, I think. They take tons of clones and show how they keep them clean.
SB shakes the dudes hand and tells him that’s how you run a nursery.
Some of those articles are written by the companies that want to convince people their clones need to be “cleaned” it says that these issues can be outgrown by taking healthy cuts of an infected plant. SB has preached that for years to put a mother plant outside to regenerate healthy cuts.
Sounds like Dave Watson is involved...
Among identifying HpLVd, Dark Horse Nursery has developed a functioning “clean process” under the guidance of Research Manager Will Roberts. This process, however, is currently patent-pending, giving DHN ownership over the eradication processes.
Dunnit ?
Not like the flu. More like herpes or HIV. Spread by specific means. In the case of HLVd, it appears that it is primarily passed on by diseased pollen and/or using an unsanitary tool lol.

It has only gotten worse, another case for growing your own from seed. An update-

Widespread Pathogen Plagues Over 90% of California's Cannabis Farms​

A infectious pathogen lurking within California's marijuana farms is targeting cannabis plants, lying undetected for months, only to ruin a crop just as it's about to be harvested. Researchers suspect that this pathogen is present in almost all marijuana farms within the state, potentially causing billions of dollars in damage to the nation's cannabis industry.

The Hop-latent viroid, or HLVd, causes cannabis plants to wither and can decrease their yield by up to 30%. Furthermore, it reduces the concentration of THC, marijuana's primary active compound, significantly diminishing the value of the affected plants.

HLVd was first observed in cannabis through two scientific studies published in 2019, which confirmed the viroid's presence in samples from a Santa Barbara marijuana farm. It has now infected at least 90% of California's cannabis cultivations, as per a 2021 estimate. The pathogen is spreading worldwide, with a recent scientific paper designating it as the "greatest concern for cannabis" growers globally.

However, a Bay Area startup has developed a novel tool they believe will halt the pathogen's proliferation.

Oakland-based Purple City Labs introduced a new HLVd test earlier this year that can be performed on-site and provide results to marijuana farmers within a few hours. This is a significant improvement over the current methods of detecting HLVd infections, which generally involve farmers sending samples to labs and awaiting results for days or even weeks.

The company asserts that this on-site testing could be crucial in curbing the global pathogen's spread, as it enables farmers to swiftly identify infected plants.

Luke Horst, director of business development for Purple City Genetics, said, "We didn't just identify a great test that is accurate, but it's [also] easy to use and doesn't require a high level of expertise. You can take microbiology to the public and put it in their hands... It's important for people to have this type of testing."

A stealthy menace on marijuana farms​

HLVd has likely been infiltrating cannabis farms for over a decade, but initially, cultivators were unsure of what was damaging their crops. Dubbed "dudding," the affliction would only manifest towards the end of a plant's life cycle, altering its form and reducing its active compound production, such as THC, by up to 50%. This impact can devastate a crop's retail value.

HLVd's delayed symptoms make it a particularly insidious threat to contemporary cannabis farming. Farmers typically cultivate cannabis by cutting small pieces from a single plant, often referred to as the "mother," which are then used to propagate hundreds of new plants.

These mother plants are deliberately prevented from flowering, enabling them to continuously produce offspring. However, this also postpones the appearance of HLVd symptoms, allowing a single infected mother plant to quietly spread the pathogen for months without exhibiting any signs of infection.

HLVd was initially identified in hop plants, a close relative of cannabis, in the 1980s. Today, it is commonly found in hop farms, where it reduces the production of aromatic compounds used primarily to flavor beer.

By 2021, following its initial discovery in cannabis in 2019, the viral pathogen had infiltrated at least 90% of California's marijuana farms, as indicated by a survey that examined 200,000 California cannabis plants. The viroid has now extended its reach to marijuana farms worldwide, from Massachusetts to Europe.

Rapid Results Inspired by Pandemic Solutions​

Ali Bektaş, CEO of Purple City Labs and lead author on a 2019 paper identifying HLVd in cannabis, began working on an HLVd test after joining Purple City Genetics, a renowned Oakland-based cannabis nursery, in 2021. Initially hired to assist in developing new cannabis strains, Bektaş soon recognized that HLVd testing was a significant challenge for the nursery.

With hundreds of samples sent to labs each week, the nursery often faced delays of several weeks before receiving results, enabling the pathogen to spread rampantly. Bektaş, a Ph.D. holder in microbial ecology from UC Berkeley, recalled a testing method called LAMP that he had worked on during his studies and had gained popularity amid the COVID-19 pandemic. Unlike PCR tests, LAMP technology is cost-effective and can be accurately operated by almost anyone.

Bektaş believed LAMP technology could be applied to combat the viral threat to cannabis. Collaborating with the Oakland Genomics Center, he developed a straightforward LAMP test for HLVd, enabling the nursery to rapidly test thousands of plants and obtain results within hours.

Soon, other industry farms began inquiring about using the test. Bektaş explained, "We didn't develop a product to sell it. We made it to use in the nursery. But it was just perfect for this particular problem. We weren't even advertising it, but people would hear about it, and they would start asking us if they could also use it."

Now retailing the technology at $10 per test, the company has begun distributing it globally. Bektaş recently traveled to Spain to showcase the product, where he discovered HLVd in a plant during the first test. "They assumed it was going to be clean because it was in Spain. But we tested it twice, and both times it came back positive," he said.
Excellent info but very scary. I had no idea about this but when things get so mass produced bad things happen. many of us like bananas too but they are all clones of one variety and that is also scary for something similar that could wipe out all banana trees. Looks like sharing clones is dangerous for more than mites. Plant the seed and be nice and plant Nice…
The Earthbox and Probiotic Farming: Kevin Jodrey, Alan Adkisson & Patrick King

NOTE: I share this video primarily for the info it provides on the ability of probiotics to effectively ward off HLVd. Jodrey mentions that he worked with a team of PhD Virologists, from several California universities, on ways to cure and prevent HLVd. This is a relatively old video and Gro-Kashi is now called 'King-Kashi', and available only in the USA.

Dr. Tassa Saldi: HLVd "is Wiping Out Home Grows & Commercial Facilities, AROUND THE WORLD!"

Uncovering The COVID of Cannabis - HLVD, Hop Latent Viroid

Hop Latent Viroid: A Hidden Threat to the Cannabis Industry (03•04•23)

EDIT: While the topic of foliars wasn't raised by Kevin, that I can remember offhand, outdoor probiotic growing includes regular EM-1 foliar spraying. It got over-looked by Kevin probably because he uses the Earthbox System indoors, with strict controls.

That video is 7 yrs old, but it sounded to me like Kevin was attempting to get the outdoor craft growers in the Emerald Triangle to adopt the Earthbox Probiotic Growing Method; in which case, the foliar program would include regular EM-1 sprays.

EDIT 2: Supercharge Your Soil and Body With Lactic Acid Bacteria Serum - Homemade Probiotic Fertilizer: LABS || Garden Like a Viking

Cheers! - FF
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