Leaf Septoria Fungus Problem


Hi all,
Seeds: AK-47, Autoflower, purchased from ILGM in Nov 2017 (Tasmania)
Situation: Sprouted/Germinated seeds(seed starter mix) as per ILGM directions under 2 x 18 W Grolux fluorescent tubes.
One of two seeds germinated. Tomorrow(Wed) is week three. Approx 3-4 days ago I cut off and discarded the first set of true leaves, after a yellow spot on each leaf developed into pustules that grew into irregular patterns and spread throughout each leaf ending with the leaf becoming brittle, then dry and cracking. At that point I researched and have determined it is leaf septoria fungus. HORROR… already other new leaf growth has/is developing minute golden yellow spots on a otherwise healthy plant. I have treated the plant with a copper based fungicide and I am dubbing the yellow spots with Sesame oil. Research suggests sesame oil “kills septoria fungus” BUT other research says once an infection has taken hold, all one can do is treat the infection. Sigh…
We had a cold period here in Tassie post germination( 7-15 deg C for 7 days) I left the germinating heat pad on help keep the seedling warm, I may have contributed to this issue.
Is it worth persevering with this plant? OR am I putting my other plants in danger of catching this fungus?

I grow outdoors and am worried the spores will spread. I have clones arriving in two weeks and am very worried. But, I am interested in trying to save my first AK-47 and get past this fungus problem. If you do not try…

Can septoria be carried in a plant’s genetics? OR does it develop when/if given the perfect conditions? I grow Snapdragons(Nemesia strumosa) which are very susceptible to their own version of leaf rust(Antirrhinum rust) so I am very familiar with spotting the tiny golden yellow colored fungus spots on plant leaves. At first sight I thought I may have transferred the Antirrhinum rust onto the AK-47, but research suggests each plant species has its own unique leaf septoria fungus.
In your experience with leaf septoria, outdoors, what is the best plan of attack?
I look forward to a/your reply,
Regards, Brandy


First,sorry to hear of your problems. Second welcome to ILGM.

I have no experience with this type of disease but someone more knowledgeable should be around to help you.

Hang in there


@bob31 @Countryboyjvd1971 @Donaldj @Hogmaster


Hi can we have some pictures?


Read this guide and see if it helps.

By the way, this article says its not lethal so don’t cull your plant


This photo was just taken. Notice the yellow spots beginning to grow on the leaf, the area is shining due to treatment with sesame seed oil. Unfortunately the fungus appears to be spreading.

The sequence of pictures is from just now to a few days ago where my hand is in the photo, clearly showing leaf septoria fungal infection, this discoloured and damaged leaf grew from a tiny yellow spot visible in the other photos. I knew it was bad when those first set of true leaves crumbled in my fingers, I cut them off and discarded in the bin. Obviously the fungus has and is spread throughout the plant. Shame as it looks and is healthy otherwise. Tomorrow is week three and they are outdoors now full time. I might try a “mixed herbs” remedy from Ed Rosenthal’s G. Handbook before I rip out and discard.
This(the AK-47)purchase was an experiment and bit of fun for me before my clones(northern lights variety)arrive in the next few weeks. I still have 3 of the 5 seeds purchased from ILGM. Even though December is Australia’s first official month of summer, down here in Tassie we experienced a cold week of temps 7-15 deg C(we had the fire going). I feel that week of cold and rain allowed the fungus to emerge, while I was trying to keep the newly germinated seedling alive. I don’t have anything fancy, just a light hood(re: first post) on yoyo’s sitting on the kitchen table(germinating heat pad).
I appreciate all and any advice, but a little voice is telling me to discard this plant, clean, disinfect and fumigate my house and grow area and put this down to experience, and a lesson to wait until mid Dec’ before germinating. If anyone thinks I should stick with it and persevere I welcome your opinion, BUT I do not want this fungus spreading to other plants therefore I am very hesitant to allow it to live.
The one question I cannot stop thinking about is how the hell did leaf septoria get into my kitchen?.. I have never had any diseased plants. I trimmed my last crop in April 2017 in the kitchen after curing in the shed, nearly eight months ago. Beats the hell out of me where it came from, unless the spores are everywhere just waiting for the right opportunity…which I made available for them due to my inexperience growing from seed…Bummer
Regards, Brandy. Oh, PS: What the hell is going on in the United States…


Ok make sure you have very very good drainage and good ph water and give the plant some supertherive or something to get its natural defenses up.
Then and only then look for some antifungal remedies


Yes, thank you. I have read this as well as many other articles and research on Leaf Septoria. In summary after much reading it seems once an infection takes hold, they are very difficult to eradicate. If I could I would isolate the plant, as I do not want the fungus to spread not to infest my garden with spores, that will attack other plants in the future.
I just posted some photos @ ILGM showing the timeline of the leaf septoria fungal infection.
Thanks for the reply.


Pictures attached…thank you for any assistance…



I hope you checked out what @MAXHeadRoom had sent you. Cause what you have going on I believe isn’t Leaf Septoria case in point the pic shown here below doesn’t look like anything you have on your plants


your plant (s) don’t look like this they look to be over watering over watering can cause what your plants look like


Thank you mr. Moderato


Your Welcome Mr. @Fever…lol


HI Garrigan 65,

Thanks for the tip. The AK-47 is now outside and had its first night time/dark period after being under lights for three weeks.

Being new to growing from seed, I welcome all and any views and opinions, and note the over watering advice.

I will back off the water and observe the AK for the next week…



Good deal. Keep us posted ok and good luck on your grow.

Will thumb