Any idea what this is? Effects lower, older leaves first which eventually turn brown and die but is present the entire life of the plant so I’m assuming it is a disease. Prevents lettuce from reaching maturity and stunts growth.
Help Identify Lettuce Disease and/or Deficiency
Maybe. It looks like some pictures of anthracnose too and not others. The thing is when it comes to leaf diseases, there is always some photo that almost matches your pictures but the rest don't.
Your pictures don't show real good detail so that we can see the real texture of the marks. Is the white marks on photo 2 and 3 mildew or is it skeletonized? What happens when you pull one of the plants apart? What's inside?
What are the small bugs on picture 2 and 3? Do you have a closeup of them? Are there any shotgun holes, going back to the suggestion of flea beetles on your other post? Have you looked into the center of the plant for the very small thrips? You never commented on any of the suggestions on your original post. One of the best parts to examine is between the dead area and the living area of your first picture.
Where did you get the soil from? Do you use herbicides? Any chemicals? Fertilizer? My water ph is 8 also and I don't have these problems.
At this point, you should bring them to the extension center.
Here in Morristown, we have a good agent that runs Snyder Farm and is very knowledgeable. If you don't get any results down there, try him.
Have you had this disease for more than one year? Are these pictures from this year?
The inside and tops seem healthy. The texture is not fuzzy or powdery at all “skeletonized” seems like a good adjective lol. This is in a large wicking bed bottom fed from my constant flow aquaponics system. The soil is 1/3 compost 1/3 peat 1/3 perlite & vermiculite mix. I do grow in it year round and will start treating the soil and plants weekly with neem oil
So the brown areas on the bottom, are they wilted and soft or crisp?