I and many other members on the farm have been searching for a thread on this to no avail. Hopefully this thread helps us figure out what, exactly, this dudding syndrome is.
So when I clone off of a mother plant I have a few genetics that will throw "duds". dud plants grow regular until some point in the first two months when they will suddenly stop normal growth, throw out tiny leaves with lots (7-9) of blades, lots of nodes, and usually will throw large mature pistils at the nodes. Trying to bend the branches usually will break the branch off, and over time the plant's healthy leaves will turn necrotic and begin twisting/dying.
Plants that dud out never produce a decent yield and almost always have a sub-par smell (if any) and very few trichomes. They also smoke like shit.
I'll dig through for some pictures but it's strangely difficult to photograph, even next to a comparison plant.
Any ideas as to what we're seeing? I'm looking near and far for a lab that can do testing for various viruses, the top of the list are Barley Yellow Dwarf Virus (transmitted by aphids) and Fusarium, although these syptoms don't match the syptoms of fusarium I've heard reports from commercial growers of duds testing positive.
Another possibility is a carbon drain on the plant due to an overabundance of nutrient-mobilizing fungi, @DowNwithDirT was looking into this and hopefully can swing in to shed some light (he's been busy winning cups and popping beans so we'll see)
Even still, it could be caused by some sort of change in the media when soilless media is overwatered (oxygen deprivation : overfertilization?) since this problem seems to be mostly in soilless mixes.
let's go, what you got to add?!
This post has been edited to add the following:
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Dark Heart Nursery Identifies New Pathogen, Creates Patent-Pending Process for Testing and Eliminating Cannabis “Dudding”
March 7, 2019
OAKLAND, Calif.--(BUSINESS WIRE)--Mar 7, 2019--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.
ABOUT DARK HEART NURSERY
Dark Heart Nursery is one of California’s oldest and most respected cannabis nurseries. Based in Oakland, California, the company employs 63 staff members at three locations and focuses on producing ultra-high-quality pest and disease-free plants. Dark Heart Nursery also invests substantially in research, plant genetics and pathology to ensure its customers are always afforded the best chance of success. For more information visit darkheartnursery.com
Dark Heart Nursery is now offering diagnostic and curative services for HpLVd to licensed cannabis businesses throughout California. It is likely that there are other unidentified pathogens which infect cannabis; DHN’s team is available to identify suspect pathogens on a contract basis. DHN’s team is also available for general consulting engagements. Interested parties should contact Melanie Nash at
[email protected].
ABOUT DR. JEREMY WARREN
Dr. Jeremy Warren received his B.S. degree in biochemistry from the University of California at Davis in 2000 and his Ph.D. in Plant Pathology from the University of California at Davis in 2015. He pursued postdoctoral research at the University of California at Davis and has over 20 years of experience in the field of plant pathology. He recently accepted a position at Dark Heart Nursery as Director of Plant Health.
ABOUT WILL ROBERTS
Will Roberts has a B.S. in Soil Science from Humboldt State University and a M.S. in Environmental Management from the University of San Francisco. He has over a decade of agricultural research experience and has been with Dark Heart Nursery since 2012, including nearly five years of experience in cannabis tissue culture.
ABOUT HOP LATENT VIROID (HpLVd)
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.
www.darkheartnursery.com
RESOURCES:
Visual Resources -
https://goo.gl/LhE8k1
REFERENCES:
A.N. Adams, D.J. Barbara, A. MortonEffects of hop latent viroid on weight and quality of the cones of the hop cultivar Wye Challenger
Ann. Appl. Biol., 118 (1991), pp. 126-127
D.J. Barbara, A. Morton, A.N. Adams, C.P. GreenSome effects of hop latent viroid on two cultivars of hop (
Humulus lupulus ) in the UK
Ann. Appl. Biol., 117 (1990), pp. 359-366
J. Matoušek, L. Trnĕná, P. Svoboda, P. RůžkováAnalysis of hop latent viroid (HLVd) in commercial hop clones in Czech Republic
Rostlinná výroba, 40 (1994), pp. 973-983
H. Puchta, K. Ramm, H.L. SängerThe molecular structure of hop latent viroid (HLV), a new viroid occurring world-wide in hops
Nucleic Acids Res., 16 (1988), pp. 4197-4216
View source version on businesswire.com:
https://www.businesswire.com/news/home/20190307005678/en/
CONTACT: Dark Heart Nursery –
[email protected]
Media Inquiries: Laura Braden Quigley
[email protected]
KEYWORD: UNITED STATES NORTH AMERICA CALIFORNIA
INDUSTRY KEYWORD: HEALTH ALTERNATIVE MEDICINE NATURAL RESOURCES AGRICULTURE RESEARCH SCIENCE
SOURCE: Dark Heart Nursery
Copyright Business Wire 2019.
PUB: 03/07/2019 01:48 PM/DISC: 03/07/2019 01:48 PM
http://www.businesswire.com/news/home/20190307005678/en
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