Interveinal chlorosis is a symptom of magnesium deficiency. Deficiency which might hinder the chlorophyll formation and thus causing the chlorosis in younger leaves. Chlorosis in the older leaves might be due to the nitrogen deficiency mainly which is not obvious in your case since you have fertilized plants. It could also be due to the deficiency of Mn or zinc.

I dont think ..it is any kind of nutrient deficiency....since symptoms are so sectorial in nature. Have you checked out for temperature and humidity conditions...??

I dont think this symptom related to any nutrient deficiency. Check growth environment or viral, bacterial or fungal effecs.

Mg deficiency

Dear Veli Uygur, I guess you are right. I am testing plants for pathogens.

Hi, its not look like a biotic disease, its may toxicity effect or mineral deficiency.

Check for Virus, it looks similar to Bendi or okra yellow vein disease. However, in one of your photos I also see symproms of leaf minor damage.

You can collect a leaf or more of those showing the symptoms, grind them and mix with buffer (e.g., phosphate buffer 50mM) and then use the extract to rub inoculate healthy plants (you can use carborundum powder for that or just make limited, controlled wounding with sharp object). If the symptom appears on the treated plants then at least you know that it is either a viral or bacterial pathogen and not a physiological phenotype.

Yes, I agree with Ahmed. If it is due to a leaf minor, you can see a wave or lace work like patterns on the leaves. It feeds between epidermal layers. Any so, then any systemic insecticide can take care of it. It is a common pest for all solanecious crops. I hope this helps.

All plant with such symptoms were infected by Dickeya solani, and all asymptomatic plants were negative in PCR test.

Thanks for the update Alex. I wonder how did you decide to specifically test for this pathogen?

It was one of 10 pathogens that we test on regular base (We have commercial diagnostic lab for potato and vegs)

First , Spray Trace elements fertilizers high in Mg with good suppler , check the symptoms after 5-7 days , if disappear that is OK , If not send leaf samples to virus lab. , thanks

that looks like a dosing issue (pH) in hydroponics.

could be transplant shock in soil.

the most common nutrient deficency is N, which is easy to establish PAN. I do agree w/ Sudad, Mg from the description, but seeing it, not sure, check irrigation / fertigation pH, strength, Cl-, B. Good lick ans let me know what happens.

David