Dud Identification Collective Knowledge.

[high life 45]

So stoked to see the thread go from this:

To this!

Josey what are the environmental and horticultural differences between your bro who has never seen a dudd on his dubb and yours?

Media? nutes? etc? if its fungal based, perhaps you have spores somewhere on a piece of equipment like a carbon filter or fan that you have had at your grows...

 

[Storm Shadow]

I thought it was worth noting this article... 2009 SoCal outbreak of these guys.. That's around the time this problem was born ​

http://alfalfa.ucdavis.edu/+symposium/2010/files/ppt/CAS10_19_LongStemNematode.pdf​

Alfalfa Stem Nematode​

•Found in alfalfa in California prior to 2009, but not causing much​

damage.​

•2009 first record of widespread significant yield losses followed by​

another bad 2010 year with increased damage. Losses primarily​

in the Sacramento and Northern San Joaquin Valley.



http://agadapt.ucdavis.edu/alfalfastemnematode/

Alfalfa Stem Nematode and its Link to Climate Change in Yolo County

Alfalfa stem nematode outbreak in Yolo County

Alfalfa is a major crop in Yolo County, accounting for 17% of all irrigated acres in 2008. While nematodes and other pests have always been of concern for alfalfa farmers, a large outbreak of alfalfa stem nematode in 2009 and 2010 resulted in significant losses in yield countywide. In response, local growers, extension staff, and scientists are working to understand what factors may have contributed to the outbreak and what solutions may help control the pest.

What is alfalfa stem nematode?

The alfalfa stem nematode is a parasitic roundworm in the phylum Nematoda. It's life cycle begins with an egg. After hatching, the nematode molts two times to become an infective juvenile. The juveniles can live in the soil and withstand extreme temperature and moisture fluctuations. During favorable conditions, the juveniles travel up the stem of alfalfa seedlings and enter the plant through the stomata. Once within the plant, the juveniles undergo another molt to enter the adult stage. Plant hormones are released by the nematodes that stunt growth and swell plant tissue (Figure 1). Adult females can lay 200-500 eggs within the alfalfa plant. The average generation time is 19-23 days at 41-86 deg F [2].

What are the symptoms?

• leaves small and "mouse-eared" in appearance
• shortened internodes and swollen nodes
• plants appear yellow or white in color ("white flagging")
• brittle stems that are easy to break off

Figure 1. Normal internodes with no swelling of nodes on healthy stem (left) compared with shortened internodes and swollen nodes on the infected stem [2].

What are the possible links to climate change?

While the exact cause of the recent stem nematode outbreak is unclear, an increase in winter temperatures is likely to be an important contributing factor. Stem nematodes do not actively reproduce below 41 deg F [3]. In Yolo County, average minimum winter temperatures have increased increased 3 deg F since 1983 and are currently approaching the lower reproductive threshold (Figure 2). Higher temperatures allow the nematode to compete a larger number of breeding cycles during the winter and thus impact the severity of the infestation. If climate change causes winter temperatures to rise further, outbreaks of alfalfa stem nematode may become more frequent in the region. Additionally, the use of organophosphates and carbamate in alfalfa crops has decreased 50% since 2005 (source). These pesticides are known to suppress stem nematode populations, but are being replaced by pyrethroids, which do not affect the stem nematodes. Consequently, the decreased use of these pesticides may have also played a role in the recent outbreak.

Figure 2. Average minimum monthly ambient temperatures in Davis, CA November to February 1983-2010 [1]. The lower reproductive limit of stem nematode females is 41deg F [3].

How does alfalfa stem nematode spread?

Alfalfa stem nematode can be transmitted through plant debris, irrigation water, soil and farm equipment. Once a nematode outbreak occurs, effective treatment options are limited. However, certain precautionary measures may help prevent the introduction of ASN and/or limit its spread to other fields.

• Farm equipment should be washed before and after use.
• Irrigation runoff from infected fields should be directed away from other fields.
• Crop rotation with non-host plants can reduce nematode populations
• Livestock manure can contain stem nematodes, and livestock grazing can aid in dispersal

How can alfalfa stem nematode be controlled?

In addition to the methods mentioned above, farmers can also use varieties of alfalfa that are resistant to stem nematode. As of 2011, 53 varieties of certified-eligible alfalfa seed with high stem nematode resistance (>50% individuals resistant) are available to farmers [4]. However, plants with high resistance can still become affected by stem nematode. Varieties with higher levels of resistance are under development and should be available in a few years.

 

[Elmer Bud]

G`day Stormy

Now that is a fine piece of cut and paste Son !
I`ll even consider letting you off for the power posting earlier .
Redemption . 55 .

This .

Plant hormones are released by the nematodes that stunt growth and swell plant tissue

I have thought for a while that the plants hormonal systems were being messed with . As well as the phloem .
But the traditional pathogens we have looked at don`t mess with hormones . So nice lead .

Still ... Get it to a lab !!

Thanks for sharin

EB .

 

[Grizz]

sent a stem with buds and some root matter today,

 

[RetroGrow]

sent a stem with buds and some root matter today,

Yippee!!!
GG4?
Dud, or not dud?

Re: your post 1119-See post 1116:
"Yes, keep in mind that these can remain dormant for 3-5 years before emerging, can be passed by seed and often go hand in hand with other pathogens, which may emerge as plants immune system is compromised." In other words, maybe only one seed in a hundred has the capacity to pass on a pathogen, so it emerges only occasionally. That theory does not explain the cuts, though, so the mystery continues. The testing is a big step, and our best shot at getting a definitive answer.

 

[Loc Dog]

Has anyone with duds seen this kind of root growth?

Easily identifiable root-knot nematode, which is bad alone, but also amplifies Fusarium damage.

[FONT=Arial, Helvetica, sans-serif]The stem nematode, Ditylenchus dipsaci, uniquely lives above the ground and does not infest roots. Initial symptoms arise in stems, branches and leaf petioles, which swell and become chlorotic. Stems subsequently become twisted and distorted with shortened internodes. Plants are stunted. D. dipsaci is found in North America, southern Africa, Australia, and temperate areas of Asia.

That sounds exactly like the pictures of dud cuts from the contest. All twisted, and branchy.
[/FONT]

 

[Sam_Skunkman]

Alfalfa Stem Nematodes

Alfalfa Stem Nematodes

http://utahpests.usu.edu/IPM/htm/field-crops/insects-and-diseases/alfalfa-stem-nematode


Nasty little beast!

The first photo (Fig. 4) Note the needle-like stylets in the heads of these alfalfa stem nematodes.
Next photo (Fig. 5) Dried, but still living nematodes on the surface of leaf debris in a sample of “brown bag” alfalfa seed.
Next photo (Fig. 6) Hair-like, dried nematodes (still living) on the surface of this alfalfa seed from a “brown bag” source of seed.
Next drawing is damage in Cannabis from stem nematodes.
Last is a drawing of a Nematode.

The truth is seeds can give you nematodes, but I have never seen these on Cannabis seeds.
-SamS

 

[Grizz]

in Arizona we plowed up many a field of alfalfa due to those little bastards, hoping the test comes back positive for them but I am not seeing it.

 

[Grizz]

Has anyone with duds seen this kind of root growth?

Easily identifiable root-knot nematode, which is bad alone, but also amplifies Fusarium damage.

View Image

[FONT=Arial, Helvetica, sans-serif]The stem nematode, Ditylenchus dipsaci, uniquely lives above the ground and does not infest roots. Initial symptoms arise in stems, branches and leaf petioles, which swell and become chlorotic. Stems subsequently become twisted and distorted with shortened internodes. Plants are stunted. D. dipsaci is found in North America, southern Africa, Australia, and temperate areas of Asia.

That sounds exactly like the pictures of dud cuts from the contest. All twisted, and branchy.
[/FONT]

no I haven't, all my roots look normal

 

[xxxstr8edgexxx]

http://nematology.ucdavis.edu/faculty/westerdahl/courses/204NEM/PHWT.htm

 

[RetroGrow]

http://nematology.ucdavis.edu/faculty/westerdahl/courses/204NEM/PHWT.htm

As with broad mites, there is a temperature and time of exposure that will kill them, but the timing has to be more precise with these, it would seem.

 

[RetroGrow]

[/QUOTE]The alfalfa stem nematode is a parasitic roundworm in the phylum Nematoda. It's life cycle begins with an egg. After hatching, the nematode molts two times to become an infective juvenile. The juveniles can live in the soil and withstand extreme temperature and moisture fluctuations. During favorable conditions, the juveniles travel up the stem of alfalfa seedlings and enter the plant through the stomata. Once within the plant, the juveniles undergo another molt to enter the adult stage. Plant hormones are released by the nematodes that stunt growth and swell plant tissue (Figure 1). Adult females can lay 200-500 eggs within the alfalfa plant. The average generation time is 19-23 days at 41-86 deg F [2].[/QUOTE]

Note: Alfalfa Stem Nematode=Ditylenchus dipsaci.
What's puzzling is, why aren't outdoor grows being devastated by these? Perhaps because most large outdoor grows are in Northern California?
Also note that fusarium is often a secondary infestation after Ditylenchus dipsaci, which would explain a lot. One issue: according to that link, "Alfalfa is the only known host", however this information conflicts with other info I already posted: Post #1112.
So we have conflicting info, it seems, unless I'm missing something.
At any rate, SEND FOR TESTING. ONLY WAY TO BE SURE. IT'S NOT ILLEGAL VIA FedEx/UPS.

 

[Mister_D]

Just wanted to say, HUGE to all those that have, and continue to work towards identification and treatment of whatever this turns out to be. My hat is off to all of you

 

[Storm Shadow]

Good Info

http://www.garlicgrowers.on.ca/documents/GGAO-celetti-bulb-stem-nematodes-garlic.pdf

These guys make every other bug look like cupcakes ....

I drenched my warehouse babies with a triple death combo...Chitosan, Kontos, Azoxystrobin

Couple more days...time for a heavy dose of Conserve SC aka Spinosad...

I did a 24k grow of Tahoe OG from Progressive Options...and not one plant went DUD ... I remember only using 1 dose of Pylon + Spinosad and everything was perfect

Also I did another grow in that warehouse prior to the Tahoe from PO with more PO genetics and I just used Triple Action Neem Oil for a month b4 I flowered and not one DUD...

Just notes worth mentioning

 

[whatthe215]

Holy shit I just confirmed nematodes inside of a dud plants stem.

I took the outer layer of a badly affected plants stem near the base and threw it under 200x microscope... and boom! Instantly saw them flopping around.

Great job SS. FUCK...

BTW these fucks just took out a 12kw room of mine, chopped what I could yesterday at day 32. Coco beds. I think high temps increase their activity.

 

[whatthe215]

No root knots or tumor like things... just nematodes swimming around in stem tissue.

 

[whatthe215]

I tried to take pics but the camera can't take pics through the microscopes lens. 99% sure they're nematodes. I'll try to get a sample to labs before I take everything to the dump...

 

[RetroGrow]

Good Info

http://www.garlicgrowers.on.ca/documents/GGAO-celetti-bulb-stem-nematodes-garlic.pdf

These guys make every other bug look like cupcakes ....

I drenched my warehouse babies with a triple death combo...Chitosan, Kontos, Azoxystrobin

Couple more days...time for a heavy dose of Conserve SC aka Spinosad...

I did a 24k grow of Tahoe OG from Progressive Options...and not one plant went DUD ... I remember only using 1 dose of Pylon + Spinosad and everything was perfect

Also I did another grow in that warehouse prior to the Tahoe from PO with more PO genetics and I just used Triple Action Neem Oil for a month b4 I flowered and not one DUD...

Just notes worth mentioning

Why do you keep going to PO? That place is Vector Inc.

 

[Grizz]

Holy shit I just confirmed nematodes inside of a dud plants stem.

I took the outer layer of a badly affected plants stem near the base and threw it under 200x microscope... and boom! Instantly saw them flopping around.

Great job SS. FUCK...

BTW these fucks just took out a 12kw room of mine, chopped what I could yesterday at day 32. Coco beds. I think high temps increase their activity.

did you just pull the outer layer of skin on the stem ? or cut a cross section of the stem, have a scope coming tomorrow and want to know .

 

[RetroGrow]

Beds make it easy for them to spread, I'm guessing.