Chris DeWildt

November 12, 2018 3 min read
November 12, 2018
3 min read

Growers Network’s Disease Profile: Pseudomonas cannabina, a Bacterial Cause of Blight

Do you want to be part of our private, professional community?
Join Now

In this series of articles, Growers Network talks about a few of the most common Cannabis diseases you need to watch out for. Today’s topic: the bacterium Pseudomonas cannabina, a cause of blight.

GN logo

Plant diseases can be a nightmare in any grow operation and Cannabis has no shortage of diseases that would love to ruin your crop. So for today’s profile we’re going to discussPseudomonas cannabina a bacterial blight pathogen you may find yourself dealing with in your grow.


Quick Look

  1. Common Name: Bacterial Blight
  2. Scientific Name: Species of the Pseudomonas genus, including Pseudomonas cannabina
  3. Symptoms: Yellowing leaves, water-soaked lesions, necrosis of lesions
  4. Caused by: Bacteria
  5. Timing: Anytime conditions are cool and wet


Pseudomonas cannabina

P cannabina
This is Pseudomonas cannabina, a cause of blight.


What is Pseudomonas cannabina?

Pseudomonas cannabina is a flagellated bacteria that causes blight on leaves. The symptoms can often be mistaken for Brown Leaf Spot, Septoria, a nutrient deficiency, or symptoms due to overwatering. It is spread most often by water through irrigation. It’s important to note that “blight” is a general term for the symptoms caused by several fungal or bacterial vectors.

What to look for

As previously mentioned, symptoms include leaf lesions as well as stem and leaf rot. Lesions show as tan or brown spots haloed in yellow.

blight
This is what blight looks like on Cannabis (photo courtesy of nexles.com)


How to Treat/PreventPseudomonas cannabina

Treatment

An issue in treating blight is that it isn’t immediately apparent whether the symptoms are the result of a bacterium such as P. cannabina or a fungus. Fortunately there are many commercial bactericide/fungicide combos available to treat blight.

Writer’s Note: Always be aware of the laws and safe practices regarding pesticide use in your jurisdiction, and only use products according to the manufacturer’s instructions.

Prevention

Prevention of Bacterial Blight begins with the environment. Make sure you aren’t overwatering, as Pseudomonas cannabina thrives in wet conditions. Additionally, keep adequate space between plants to reduce likelihood of spread. There are also air sanitizers available that will kill microbial pathogens before they can start causing havoc for your operation.


So now you know a bit aboutPseudomonas cannabina and what you can do to prevent it from ruining your grow. Have additional questions about this bacterial disease vector? You should join our forum where you can post pics and ask our expert community about this topic or any other!

Happy Growing!


Enjoyed the article? Want to continue the conversation?
Join Now

Do you want to receive the next Grower's Spotlight as soon as it's available? Sign up below!


Do you have any questions or comments?

Feel free to post below!


About the Author

Chris DeWildt is a graduate of Grand Valley State University and Western Kentucky University. He worked in education and publishing for ten years before joining the team at Growers Network.