Virus in my growroom- expert advise needed!!

[avidgardener]

Hi There
Something is devastating my grows and I suspect a virus or fungus is the culprit. I am an experienced grower but this has me stumped. First of all – I grow in Bio Bizz All-Mix soil and use Bio Bizz Gro and Bloom in 75% RO mixed with 25% tap water. I have ample in/out fans and 2000 watts of light. RH is around 50%. Temps 27c on 22 off. I have been doing this succesfully for almost 20 crops until a year or so ago.
The problems start at a couple of weeks into flowering. Small spots appear on the fan leaves which grow and rapidly turn brown. They spread over the leaf which eventually turns brown and drops. Some of the branches wilt and feel sort of hollow if that’s the word. You only have to squeeze them gently and they squash. They don’t appear to rotten inside. Later on the symptoms can appear anywhere on the plant. The spots tend to have a yellow halo round them.
This, whatever it is, is reducing my yields by 50% or more. I’ve tried cleaning like a madman between crops but to no avail (scrubbed and bleached everything twice). I’m on my 4th fucked up crop now and I don’t know what to do. Any help is really appreciated.
Cheers
IPAS62

 

[shopvac]

looks like a case of ph shift, have you checked that recently?

 

[Guest]

How old are they?Tap one out of its pot & have a look at the roots. Have they been in those pots from the begining

 

[gladysvjubb]

Personally.....

Personally.....

it looks like a grow mix problem. Try changing your mix.

 

[avidgardener]

Hi. Thanks for the replies. pH of the soil is 6.5. I water at 6.4
They are in week 7 of 12/12. They were potted up 3 times, vegged for 4 weeks. Final pot size 25 litres.
I've been doing the same method for years with no probs. The soil and nutes are Dutch and formulated for cannabis so I trust them plus they've never given me problems before.
I'll check the roots later when the lights come on - what am I looking for?
Cheers
IPAS62

 

[gladysvjubb]

OK now

OK now

that's a horse of a different color. Being that they are in week 7 of 12/12, if it's just the Fan Leaves doing it, I would say it is normal maturation and nothing to worry about. They do drop the fan leaves, reacting to decreased light from the short days.

 

[Guest]

it looks like a grow mix problem. Try changing your mix.

Pretty bad advice your giving out

 

[Pimp Aurora]

are you flushing?

 

[Tokabowl]

It looks like it could be a virus (Hemp Streak Virus)...


Here is some info on Cannabis Viruses, taken from this great page here: http://mojo.calyx.net/~olsen/HEMP/IHA/iha03111.html

Viruses
Viruses rarely kill Cannabis. They only exist and replicate in living plants. Viruses can, however, seriously reduce yields. Once acquired, they are nearly impossible to eradicate. Viruses invade all parts of plants. Pollen and seed infections transmit viruses to subsequent generations.
Five viral syndromes are described in the literature. In addition to these naturally-occurring infections, Hartowicz et al. (1971) screened 22 common plant viruses for their ability to infect wild hemp. Over half the viruses could infect Cannabis.
The hemp streak virus (HSV) is frequently cited on fiber cultivars in Europe. Foliar symptoms begin as a pale green chlorosis. Chlorotic areas soon develop into a series of interveinal yellow streaks or chevron-stripes. Some-times brown necrotic flecks appear, each fleck surrounded by a pale green halo. Flecks appear along the margins and tips of older leaves and often coalesce. Streak symptoms predominate in moist weather, flecks appear during dry weather. Leaf margins become wrinkled and leaf tips roll upward, leaflets curl into spirals. Whole plants assume a "wavy wilt" appearance.
The hemp mozaic virus has been described on fiber cultivars in Europe and drug cultivars in Pakistan. Symptoms were described as a gray leaf mosaics. Three other viruses have been cited on European hemp—the alfalfa mozaic virus (=lucerne mozaic virus), cucumber mozaic virus, and the arabis mozaic virus. Many insects transmit these viruses as they feed from plant to plant. According to Ceapoiu (1958), the worst vectors of Cannabis viruses are bhang aphids (Phorodon cannabis), greenhouse whiteflies (Trialeudodes vaporariorum), onion thrips (Thrips tabaci) and green peach aphids (Myzus persicae).

The symptoms they describe above do seem to relate to the ones you are describing.

Apparently, the Weed World Magazine, issue #42 (2002) has an article about viruses.

Ed Rosenthal also talks about viruses in some of his books,
and so do Alexander T & Parker D in "Sinsemilla Tips".



You say this has been happening in your last 4 grows... Have you been running the same genetics for the 4 grows? (clones of previous (infected) grow, or seeds from infected plants?)

I ask this because viruses aren't only transmitted by insects, wind, etc... but can actually get into the genetic composition of a strain.


Hope this helps, and I hope your harvest wont be too joepardized...

Peace

 

[dangbongdang]

this could be a long shot but maybe your nutes are expired?

 

[avidgardener]

Tokabowl - I think you hit the nail on the head. I havn't been running the same genetics but the clones were all purchased from the same place for prvious 3 crops. This time I started fresh from seed and they have the same symptoms as the clones.
I have that issue of weed world about viruses. I'm praying it's not HSV. I will be harvesting in a week or so and plan to rebuild my whole grow after disinfecting the shit out of everything. I'm looking at a product called citrox which is an organic disinfectant.
Thanks for the reply
IPAS62

 

[Guest]

Theres a product called physan 20 that works great for disinfecting a grow room. It should be at all local hydro stores. Do youself some research on it you may like what you read.

 

[avidgardener]

Thanks. I'll check that out

 

[mid-east-stone]

have same shit

have same shit

once i did something and it helped- donno what ..
this time i am lost...





any thoughts? fungus maybe?

 

[TGT]

^^ Looks like too much nitrogen. Could you be feeding too much?

TGT

 

[avidgardener]

Hi
Thanks for everyones replies.
Physan 20 costs 70 pounds (UK) over here - thats almost $150 US!!! I can only find it in one place that specialises in orchids.
I am sure I have the hemp streak virus after posting on other sites and getting the same answer.
Does anyone know if the virus will be in my weed when it's dry? I don't want to reinfect my room because of something as stupid as rolling a joint and then touching a leaf. In fact I've probably been doing that and reinfecting the room over and over. It's probably all over my house, clothes, everything.

Mid-east stone........It does look like you have something similar to me. By the way...Ani garti beisrael esrim shana!!!! Bhatzlacha!

IPAS62

 

[Pimp Aurora]

This is one of my mother plants...

Got me a bit nervous now.

 

[mid-east-stone]

hay avid!

hay avid!

so what do we do about the hemp streak virus ?
any cure against it?
it seems that all of my plants are infected...
i hope you like your new place..
here is basicly the same.. :0...
where do you also post?
m.

 

[avidgardener]

Pimp Aurora - that does look a bit viral/fungal. You can get a good spray for that called Citrofresh. I havn't tried it myself but it's highly recommended on sites in the UK.
http://www.uk420store.com/shop/product_info.php?products_id=638
Hope you ain't got it too!
Ipas

 

[Pimp Aurora]

iirc citrofresh is just a preventative barrier so now it's too late to use it, basically you can trap the virus inside.. I have some murphys copper fungicide, might give that a whirl, i'm in the uk too so you should be able to pick up copper fungicide from most half decent garden centres, failing that there is a stronger one called dithane, these cost about a fiver for a little box, the copper fungicide has 10 sachets and makes up to 40 litres.

I do know that LNIN on uk420 tried it and gave it a bad review, he ended up using copper fungicide.