Light Brown Spots on Tomato Leaves

[ArthurDent004]

I've started seeing these light brown spots starting to appear on the older leaves of the plant. The leaves don't appear to be so dry they are flaking away but they do have rougher texture. I've been looking for matching pictures but I haven't found an exact match yet. I'm leaning toward late blight but I thought I'd ask for other opinions.

[kath]

Doesn't look like late blight to me. The photos are pretty dark but could it be damage from spray of some sort?

kath

[Paradajz]

just a touch of Mildew probably, what's the color and size of those patches from the other leaf side?

br,
ivan

[ArthurDent004]

I don't know why I didn't think to look at the underside of the leaves earlier. Here's some pics. I'm now thinking mold or mildew. The white or yellow follows the leaf veins on the underside. I'll have to find a magnifying glass for a closer look.

[Paradajz]

what's the humidity status there? also, was there any cold temps lately?

you are absolutely right about the magnifying glass.

[ArthurDent004]

This plant is growing indoors so temperature runs between 70 - 80 degrees. The humidity runs between 50 - 60 percent to help pollen set. The plant is three feet tall with nine tomatoes ripening. I have a fan circulating the air but it may need adjusting.

[ArthurDent004]

I took a couple of leaves to my local extension office and they declared I had downy mildew. Under the microscope they were seeing some black spores developing so they said I needed to remove all leaves showing any infection and check the stems for spots. I also should spray my plants with a fungicide and improve my air circulation.

[kath]

Originally Posted by ArthurDent004

I took a couple of leaves to my local extension office and they declared I had downy mildew. Under the microscope they were seeing some black spores developing so they said I needed to remove all leaves showing any infection and check the stems for spots. I also should spray my plants with a fungicide and improve my air circulation.

Have you read about b54red's bleach treatment? It would be sure to treat all the leaves that have any mildew on them- even the ones you might not be able to see yet. Just a thought...

[ArthurDent004]

I finished removing the infected leaves but I'm seeing one large mildew spot on the main stem of the plant about three inches from the soil top and a couple of smaller spots about midway up the plant on some branching stems. I was looking at a seedling I have growing and notice three limbs that have mildew spots. I've clipped these limbs also. It looks like I may have to eliminate the main plant before putting the new seedling in a new SWC.