Is this Fusarium ??

[Young_Thumb]

Hi everyone !
i'm new on this forum so please be gentle and do not hesitate to ask me for more details.

First a quick presentation of my plants

Variety : Sativa
Age of the plants: Blooming W+6
Symptoms appeared : Blooming W+3,5
Contaminated parts : Stem
Evolution of the problem : Slow
Environment : Greenhouse
Kind of soil : Humus-rich

Few weeks ago i discovered that a stem on a plant was feeling deezy. When i looked closely, i saw that the knot of that stem was circled in white and pointed with black little dots.


When i tried to move that stem it broke and remained in my hand?


As the hole was done i did remain properly all the remaining black/browny things around it and apply some mastic.


Two weeks late i feel like de shadow is spreading a bit around. As i do have a plant each square meter, i'm a bit scared wondering if i'd rather cut the whole plant right away i order not to infect the other plants around.




Would appreciate any piece of advice

Many thanks for your help and have a great day !

 

[Paradox808]

It's most likely botrytis. Fusarium usually takes the whole plant out

 

[Creeperpark]

Your plants are not transpiring correctly and the stems are suffering cause of it. The plant above is suffering from excess moisture exposure. I would remove all the fabric on the ground and keep the plant's soil aerated around the trunks. Use a hand cultivator and keep the soil loose between waterings.

Dig down close to the plant about a hand deep and feel the soil before you water. Let the plant's soil dry well on top before watering again. If you water your plants when they "wilt in the heat" you can overwater easily. So don't be fooled by the plant's wilting in heat. Heat wilt and drought wilt look the same but they are not. So feel the ground before every watering.

 

[acespicoli]

https://www.researchgate.net/publication/349223256_Morpho-molecular_identification_and_first_report_of_Fusarium_equiseti_in_causing_chilli_wilt_from_Kashmir_Northern_Himalayas

Potato dextrose agar - Wikipedia

en.wikipedia.org

The interesting aspect of culturing your pathogen is you may correctly identify it
Also you may treat it with copper or sulfur captan whatever and be able to correct it on your plants
from what you learn doing your due diligence of lab work next time you see it
You know what you have and the proper corrective measure

Will add that PDA is simple to make an mason jars make excellent petri dishes

 

[Young_Thumb]

Your plants are not transpiring correctly and the stems are suffering cause of it. The plant above is suffering from excess moisture exposure. I would remove all the fabric on the ground and keep the plant's soil aerated around the trunks. Use a hand cultivator and keep the soil loose between waterings.

Dig down close to the plant about a hand deep and feel the soil before you water. Let the plant's soil dry well on top before watering again. If you water your plants when they "wilt in the heat" you can overwater easily. So don't be fooled by the plant's wilting in heat. Heat wilt and drought wilt look the same but they are not. So feel the ground before every watering.

Yeah watering may be the main issue but as everyone is on the same irrigation system and it's hard to dissociate a plant wilting from heat but as everyone around looks fine i should have knowned better..

I used some trichoderma afterwards which might reduce the stress and may feed on the bad mush. Crossing my fingers as i'm close to harvest..

Thanks everyone for those really interesting pieces of advice !

Peace

 

[Young_Thumb]

View attachment 18886830

https://www.researchgate.net/publication/349223256_Morpho-molecular_identification_and_first_report_of_Fusarium_equiseti_in_causing_chilli_wilt_from_Kashmir_Northern_Himalayas

Potato dextrose agar - Wikipedia

en.wikipedia.org

The interesting aspect of culturing your pathogen is you may correctly identify it
Also you may treat it with copper or sulfur captan whatever and be able to correct it on your plants
from what you learn doing your due diligence of lab work next time you see it
You know what you have and the proper corrective measure

Will add that PDA is simple to make an mason jars make excellent petri dishes

That's some serious work, i'm not sure i'm able to go this far

Do you have a personal lab to that ?

 

[acespicoli]

Alot of people growing this kinda stuff on last weeks dishes
nah you just boil some peeled potato skins or sliced taters and add the agar flakes to the broth, its as simple as making jello

https://web.archive.org/web/20110716090823/http://www.disknet.com/indiana_biolab/b029.htm
https://www.frontiersin.org/articles/10.3389/fagro.2021.796062/full

Figure 2 Root-infecting pathogens on Cannabis sativa. (A) Symptoms of brown discoloration on the root system of indoor hydroponically grown plants. (B) Colonies of Fusarium oxysporum isolated from diseased roots in (A) growing on potato dextrose agar. (C) Colony of Pythium catenulatum isolated from diseased roots growing on potato dextrose agar. (D) Symptoms of natural crown infection on a field-grown cannabis plant caused by a combination of F. oxysporum, Fusarium brachygibbosum, and Pythium aphanidermatum. (E) The crown area of the infected plant shown in (D) is sunken, and there is visible mycelial growth on the surface. (F) Colony of Fusarium brachygibbosum isolated from diseased roots growing on potato dextrose agar. (G) Symptoms of plant collapse as a result of infection by P. aphanidermatum under a greenhouse environment. (H) Comparison of a noninoculated plant (left) with a plant wound-inoculated with spores of F. oxysporum (right) and grown in coco fiber substrate. Photo was taken 4 weeks after inoculation and shows stunting and yellowing of leaves. (I) Symptom of internal discoloration of the pith tissue in the upper 10 cm of the crown region of a plant grown indoors in coco fiber as a substrate and infected by F. oxysporum. Figures 2A, D, E, G reproduced from Can. J. Plant Pathol. 40(4) by permission
https://en.wikipedia.org/wiki/List_of_hemp_diseases

Maybe you try to grow us a fungal bloom to identify? Either way!
From the pictures its hard to tell, does your soil drain well ? Are you using surface water from pond etc ?
Is there molds under your plastic mulch ?


Dry everything out treat the stem area with flowers of sulfur, reminds me a little of brown rot, just a guess
Crushed up match heads.... whatever fungicide you have access to
Scrape and coat with honey perhaps, hope you can save the plants

Hemp (Cannabis sativa)-Fusarium Wilt

See: Hemp ( Cannabis sativa ) - Verticillium Wilt By C. M. Ocamb Cause The fungi, Fusarium oxysporum f. sp. cannabis and Fusarium oxysporum...

pnwhandbooks.org

• Avoid planting in heavy, poorly draining soils.
• Avoid excessive irrigation, especially during the spring, but also minimize moisture stress, particularly during flowering.

https://www.tandfonline.com/doi/full/10.1080/07060661.2018.1535470

Antifungal activity of four honeys of different types from Algeria against pathogenic yeast: Candida albicans and Rhodotorula sp - PMC

To evaluate the antifungal activity of four honeys of different types from Algeria against pathogenic yeast i.e. Candida albicans (C. albicans) and Rhodotorula sp. Four Algeria honeys of different botanical origin were analyzed to test antifungal ...

www.ncbi.nlm.nih.gov

It looks a little like Nutella

>>> Best >ibes

 

[acespicoli]

Let's see and hear about your sick plants!!

...Every grower at one time or another has to face the stark reality of seeing their best plants growing sick and perhaps dying... ...On this forum we will record and investigate various plant ailments in the worthwhile persuit of hopefully helping to eradicate or at least control various pest...

www.icmag.com

Some type of stem canker perhaps ?

Canker - Wikipedia

en.wikipedia.org

Most fungicides that can be bought retail are sold in liquid form. A very common active ingredient is sulfur,[4] present at 0.08% in weaker concentrates, and as high as 0.5% for more potent fungicides. Fungicides in powdered form are usually around 90% sulfur and are very toxic. Other active ingredients in fungicides include neem oil, rosemary oil, jojoba oil, the bacterium Bacillus subtilis, and the beneficial fungus Ulocladium oudemansii.

Walmart has neem oil 70% on sale right now ! 14$ now 9$ 8oz

 

[Ca++]

I can't sleep after seeing that. The only coco I need is a hot drink, while I watch cat videos to reorientate myself.

 

[Loc Dog]

View attachment 18886830

https://www.researchgate.net/publication/349223256_Morpho-molecular_identification_and_first_report_of_Fusarium_equiseti_in_causing_chilli_wilt_from_Kashmir_Northern_Himalayas

Potato dextrose agar - Wikipedia

en.wikipedia.org

The interesting aspect of culturing your pathogen is you may correctly identify it
Also you may treat it with copper or sulfur captan whatever and be able to correct it on your plants
from what you learn doing your due diligence of lab work next time you see it
You know what you have and the proper corrective measure

Will add that PDA is simple to make an mason jars make excellent petri dishes

I started a thread about a month ago regarding whether anyone tried this.

Was hoping you could buy PDA petri dishes, since agar ones are $1 a piece pre made.

How do you prepare sample? Just touch to surface or grind and add to some solution and use eye dropper to add to dishes?

What kind of microscope?? My USB is good for mites but can not see single cells.

 

[acespicoli]

I started a thread about a month ago regarding whether anyone tried this.

Was hoping you could buy PDA petri dishes, since agar ones are $1 a piece pre made.

How do you prepare sample? Just touch to surface or grind and add to some solution and use eye dropper to add to dishes?

What kind of microscope?? My USB is good for mites but can not see single cells.

You can buy pre made and packaged PDA agar plates usually on Amazon, have to be careful about contamination a DIY laminar flow hood is easy enough to piece together. A HEPA filter and your tent air fan for example. Wash your hands with dilute bleach water and use "google- sterile technique" you will do what they call a streak with the purest sample you can collect. Which is just a zig zag and cross it with a zig zag on the gel surface. Then incubate it which is like keeping seeds warm. in 48 hours you should have a colony begin of what ever is going on there which will be visible by the naked eye.

Its a great hobby to add to your tool box
Been a while since I worked in a lab, kinda reminds you of high school science class
Should help you in the identification and treatment/prevention
Compare your plate to a poster of plant fungus bacteria

Frontiers | Pathogens and Molds Affecting Production and Quality of Cannabis sativa L.

Plant pathogens infecting marijuana (Cannabis sativa L.) plants reduce growth of the crop by affecting the roots, crown, and foliage. In addition, fungi (mol...

www.frontiersin.org

I had a nice microscope you could see amoebas nematodes and such think my lens went to 90x plus 10x eye

The Compound Light Microscope - Optics, Magnification and Uses

How does a compound light microscope work?Helping you to understand its abilities as well as the benefits of using or owning one.

www.microscopemaster.com

Slides, Cover slips, dye
I would start with petri plates the plastic ones prefilled and expand if you like the results
Hope thats helpful >>>Best>ibes Im here if you wanna get more in depth

They just cut or scrape a few infected pieces off and embed it in the gel, clean your collection tools each time

https://faculty.washington.edu/korshin/Class-486/SterileTechnique.pdf

Nice 10$ clean air work space walmart tupperware works well
you can tape long elbow length gloves to the holes from harbor freight no air leaks
Bleach or lysol spray everything down first

 

[acespicoli]

Pictorial Atlas of Soil and Seed Fungi: Morphologies of Cultured Fungi and Key to Species,Third Edition

Pictorial Atlas of Soil and Seed Fungi: Morphologies of Cultured Fungi and Key to Species, Third Edition describes and illustrates more than 515 fungal species, including: 49 oomycetous species belonging to seven genera 42 zygomycetous species belonging to 12 genera 52 ascomycetous species...

www.routledge.com

Might find this at the college or university library if you find a free pdf share it

 

[Ca++]

While doing all the sterile work, you may wish to expose a dish to the atmosphere only. It's never a bad idea to see what is floating around in the lab. Ideally, what you find on the plant, isn't in this dish. Which offers some confirmation that your clean area is working.