HELP! Leaf problem

[WhiteLeaf]

I’m growing an outdoor plant and I have it in a shady spot. I’ve noticed some issues on the leaves; in the first photo, there is partial yellowing. In the second photo, there’s another problem – do you know what it could be? And do you remove damaged leaves like this? Thank you in advance for your response.

[DabberDog]

First thought is burning. Are you near a reflective window or something that reflects light into your shady spot?

[WhiteLeaf]

Not exactly, I have it under a big walnut tree, so the shade is provided by the tree’s leaves, and the sun doesn’t shine directly there. It’s more of a shaded spot, and there’s nothing to reflect direct light. The truth is, temperatures on the sun occasionally reached up to 45 degrees Celsius, sometimes even higher. Also, what I forgot to mention is that it was briefly infested with whiteflies and flea beetles.

[Rwise]

IDK what walnut you have, but Black walnuts make an herbicide (juglone), butternut, pecan, and some hickories also produce it

[DabberDog]

Did a quick flea beetle search. They lay larvae in the soil and attack roots so maybe you have some sort of root thing going on.
An autopsy of affected stems might tell the story?

[Wayzee]

Is it in a pot? You might be able to transplant it and see if there is any colonies at the roots, the first leaf looks so so might be a little lacking in something, the second one looks like something different, is it only the one spot or are multiple sites starting to do the same thing ?
Over 45 Celcius fark that!

[Bluey]

Last flea beetle search I did for the type we get here they appear to come in from the top of the plant and burrow down into the stem...but they kill the whole plant so root attack makes mord sense to me.