In the first step , try to culture a fragment of leaf on general nutritive medium to see if there is isolation of microorganism

İ have not seen such kind symptom before. However it looks non pathogenic symptom. That is, it looks physiologic disorder.

It seems to be physiological stress.

Possibly the effect of fertilizing or spraying resistance catalysts With high temperatures, I saw similar symptoms on vegetable leaves

I think that the symptoms of dysfunction of physiological disease may be due to thermal stress and lack of moisture, or it may be due to the toxicity of a particular element absorbed by high concentration due to soil quality.

Dear professors thanks for your kindness. I hope you will be successful.

Dear Elaheh, this seems to be physiological stress, but for your personal satisfactions, you can culture some small pieces on selective medium and isolate total DNA and perform RCA. but i am sure this is not viral or bacterial infection.

Thanks for your kind mr Nawaz

It may be phosphorus defeciency.

Physiological disorder that may be caused by chemical and temperature stress.