Basil problem

[magaarakelyan]

Hello,

I'm Margaret from Armenia, it's a small country in the Western Asia with the abundance of sunny days throughout the whole year, and delicious fruits.

I have a small garden close to my house and I grow some greens/vegetables in a greenhouse.

Recently I've noticed some diseases on my Basil seedlings, and I started to conduct my own research on what it can be, how to prevent it and how to cure the disease.

The basil seedlings leaves have yellow, brownish spots, and they look like they are bolting and/or drying. I have attached the photo of the basil leaves in this email.

Since it's the first time I've been growing basil, I'd like to have an expert's opinion.

1. Do you think it's a kind of fungal disease or a pest problem? (if yes, what type of disease or pest?)

2. Is there any cure for the plants and how to do it in naturally or home-made ways? (I hope to keep my plants organic)

3. Can the same disease be transferred to other crops, such as rucola, radicchio rosso, fennel, rosemary, and how can these crops be damaged?

4. If I take all the damaged seedlings out of the soil, will the soil still have the disease inside, and if so, how can I cure the soil? (shall I take the surface part of the soil out or what you recommend?)

I'll highly appreciate your comments and recommendations on this issue.

Thank you in advance for your time and consideration.

Looking forward to your help!!!

[imafan26]

You photos did not upload.
Does it look like downy mildew in the pictures of the first link?

https://www.plantvillage.com/en/topics/ ... ropagation
https://plantclinic.cornell.edu/factshee ... seases.pdf

[magaarakelyan]

Hello,
Thank you for reply. I have uploaded the photos. According the research I have done, it's either downy mildew or fusarium wilt.

[River]

I am having the same issue. I took a couple of the plants that I have in 4 inch pots to a friend who is a plant pathologist with auburn. He couldn't study them when I dropped them off, but just glancing he thought it was bacteria. We have had an extreme amount of rain since last Sunday
Anywhere from 12-17 inches so far, and more today and tomorrow.

With these conditions if it is bacteria it thrives in these conditions. I will let u know when I get the results. I hope it is bacteria vs the other 2

[Gary350]

Your plant has a fungus infection. Move your plant outside, good air circulation, full sun all day, very well drained soil.

What are your weather conditions and soil conditions?

I use to have problems with my basil when I lived in Tennessee. Humidity was very high 95% almost all the time, 300 days or rain per year, over cast sky 75% all the time, soil very wet except in the summer, soil ph about 5.6. My basil did much better in a raised bed with well drained soil with lots of peat moss in the soil and full sun all day.

I have moved to Arizona my Basil does great here, hot, dry, no rain for 9 months of the year, sandy soil, very high ph 8, very sunny, 115 degrees in the summer and 70 degrees all winter.

[imafan26]

It doesn't look like fusarium. It does look like bacterial leaf spot. It can be transmitted by seeds and transplants. If there is a lot of damage, it might be better to bag the plant and sanitize the area. Make sure tools and hands are washed so that there is no sap transfer to other plants. Wait until the weather is drier and any inoculum to dissipate to plant more basil and try a different location.

https://growingsmallfarms.ces.ncsu.edu/g ... ilproblem/

[River]

The outcome of my basil
Here is the response from the plant pathologist. I dropped off 2 basil plants Friday afternoon
This is his reply this afternoon.

I did not find any evidence of bacteria.
It could be physiological or it could have been a very weak bacteria that got in during the heavy rains and is not a strong pathogen so it has quit multiplying and you can pull the leaves and they will be fine

[magaarakelyan]

Dear all, thank you for your responses. Yes I have had more rains recently than usual, and I think I have watered it more than it requires.

I was wondering if I could cultivate garlic (or other crops) in between the basil, rucolla, rosemary and fennel rows to prevent the crops from fungal diseases and/or pests.

[rainbowgardener]

You didn't show the under side of the leaves. That is what is distinctive for the downy mildew.

top side may have dark spots like yours:


https://bugwoodcloud.org/images/768x512/5458610.jpg

or may just show yellow banding:


https://blogs.extension.org/mastergarden ... ldew-2.png

The underside will show a distinct pattern of little dark fuzzy dots, in between veins, as it cannot cross major veins:


https://blogs.extension.org/mastergarden ... mildew.png

It is very difficult (impossible?) to cure downy mildew. Preventive use of fungicides from the beginning of the season may deter it. You mentioned a greenhouse - greenhouses with their constant high humidity levels are ideal breeding grounds for fungal diseases like this. You may need to only grow your basil outside the greenhouse, if what you have is indeed downy mildew. Organic fungicides include baking soda (sodium bicarbonate), MilStop (potassium bicarbonate), Actinovate, hydrogen peroxide, Neem oil, and others.

If you think what you have matches this description, then I would immediately trash all effective plants, since they can't be saved and leaving in the garden will help spread the disease. Let us know what you think!