How I detect and prevent budrot?

Contributed by: snoofer Thanks to: TheHerbalCultivator (images), Jorge Cervantes, vaaran Submitted: Nov 1, 2004 Images archived: 2004

Introduction

img by TheHerbalCultivatorBudrot (Botrytis) is a very common worldwide fungus that attacks both indoor and outdoor crops under certain conditions. Budrot is also known as brown rot, grey mold and other names. Airborne Botrytis spores can be found everywhere, all times of the year, and will attack many different species of plants. Botrytis will attack flowers, and eventually leaves and stems.

Growers running sea of green, perpetual harvest, remote grows, outdoor, or multiple strains (each with different flowering periods) should keep an eye out for Botrytis near harvest time.

Outdoor growers need to be hypersensitive to weather conditions near harvest time. Rain, morning dew, frost and cool fall nights may increase the risk of budrot and powdery mildew.

Fully developed marijuana buds provide ideal conditions for spore germination: warm and moist plant tissues. Botrytis will initially attack
the largest and densest buds in the garden, because they provide the ideal conditions for germination. Weak plants will also be attacked rapidly.

Identifying and preventing budrot

image by TheHerbalCultivatorBudrot will infect and turn colas to mush in a matter of days and may destroy a crop in a week if left unchecked. Botrytis loves warm, and humid (50% or over humidity) conditions. Lowering humidity will slow and stop spore germination. Good ventilation and decent air circulation help prevent infection.

A grow room may smell noticeably moldy if Botrytis has attacked one or more colas. Once a cola has been infected, Botrytis will spread incredibly fast. Entire colas will turn to brown mush and spores will be produced, attacking other nearby colas.

Ventilation may spread viable spores throughout the room.

Measures to prevent budrot in the final stages of flowering:

  • Early veg and flower pruning of undergrowth to promote air circulation
  • Hepa filter room and intake air sources.
  • Introduce low levels of ozone into room air. Ozone is effective against pollen, podwery mildew and other airborne spores.
  • Lowering room humidity (warming nighttime air and venting frequently or using a dehumidifier)
  • Decreasing watering cycles and amounts to reduce room humidity
  • Large, dense colas should be periodically inspected. Brown tissues deep within the bud will smell moldy and may become liquid.
  • Removing fan leaves during the last few days before harvest to promote air circulation
  • Serenade (thanks vaaran)

    “Serenade controls the following: …Botrytis, Powdery mildew, Downey mildew…”

    “Certified organic by OMRI and EPA/USDA National Organic Program, Serenade offers growers the luxury of application without weather or timing restrictions and there are no phyto-toxicity issues”

    “To apply, simply spray on leaves and shoots to provide complete coverage. Best results will be had be pre-treating plants before signs of disease set it and then every week to protect newly formed foliage”

    What if budrot is found?

    Once budrot has been detected, the grower should isolate infected buds by removing them from the growroom immediately and harvesting the infected colas, followed by a rapid dry of the harvested colas. Take immediate steps to reduce room humidity. Afterwards, the entire crop should be carefully inspected for infection and damage.

    The grower may want to harvest early if more than one rotting cola has been found. Spores may have spread and are germinating deep within other colas.

    Can I salvage budrot-infected colas?

    Yes. Remove the infected colas from the main room, Trim out the infection (Trim more than you can see Botrytis often infects adjacent tissues) and quick-dry them. Re-inspect buds they should not smell moldy.

    Smoking infected buds is not recommended.

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Anyone ever use a ozone generator??? I just bought one to sterilize my rooms. Has anyone used one with plants in the room?

What level mg o3 did you use? Anyone know how to make the calculation??

I have a few ambiguous pictures up in my “First grow” thread First Grow, popped in April - #146 by AllOra

If it turns out to be early bud rot I will add them to the FAQ.

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Early bud rot:



Not just buds, though after removing this mostly healthy branch I found some hidden rot in the cola.

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I just had to rip some off this morning, none last night, worse than yours by morning… damn rain

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I have my exhaust fan going 24/7 and 2 pc fans pointed at the buds (1 facing front, 1 facing side)…I dont really have a way to dehumidify the place. High rh outside…high rh inside. Any tricks to pull moisture out of the air?

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While growing or drying? How big of a space

@Tappy, you’re indoors, right? Why can’t you dehumidify?

I’ve often thought that if you yank fan leaves that stem into dense buds, it’s exposes plant tissue for infection and weakens the area to botrytis. I think your picture has convinced me.

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Growing. 6’ x 2’ x 7’ (only 3’ x 2’ being lit).

The wiring is that old school aluminum shit. I’m scared to run anything that uses too much electricity on and off.

Well shit…that sounds like something I want to avoid.

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My tent is in my spare room, with the gfs plants. We got a small dehumidifier for 100 on amazon… it’s basically table top. But knocks my humidity down about 10-15% easily. In my tent I’ve got a honeywell blaster fan for circulation (in a 2x2). On low running 24hr along with my exhaust. And I’m typically about 10-15 lower than the room.

My tent sits around 50-60%. If I notice the humidity climbing i crack the window a half inch lol. And this is in a B.C rainforest

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I’m just checking kijiji and amazon…need something that runs low amps.

Also, need to post a pic of your purple kush auto…I know I saw 1 seed for sure, but my big yield auto femmed pollen was kind of a flop.

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So here’s where in at…aluminum wiring in the basement has me hesitant to plug in a dehumidifier down here. But I have 2 pc fans blowing air at the largest buds in the room…I have my exhaust in the corner opposite to them…so they’re kind of feeding the air towards the exhaust.
Temp and rh are steady 24/7 @
19-21c 45-55%


.

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What can I do to remove moisture from the air?
Really dont want to have to get a guy over here to run a new line from the breaker.
.
It’s not even as dense as it may look…you can see the back wall through the canopy…

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If you arnt trusting a dehumidifier I’d atleast try for more fan action. Either 1 bigger one or another couple pc fans so you can move them under the canopy.

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I just looked up my dehumidifier… it only pulls 72 watts, so basically an incandescent lightbulb being left on

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You have a link? There are so many shitty products to go through. Lots with the same type of reviews…“had it on for 2 days and not a drop of water collected…”

The tank needs emptied atleast twice a week. Its sitting in an average sized bedroom in a damp basement

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If you feel as if there’s a lot of moisture in the air defoliate the bottom half as the end up being nothing anyway