Noticed this on the lowest leaves of one of my Mystery tomato plants (no idea what the variety is) Â I'm guessing Nitrogen deficiency is at fault here? The lowest truss just started dropping blossoms, producing baby fruit.

I'm guessing the only other possible cause would be disease, but it A) hasn't rained here for one single drop for 2 months and B) toms are now drip irrigated, so no splashing... I did notice some leaf miner activity on neighboring plants, but nothing beyond a leaf or two.

The plant it came from is otherwise fine

What do you think?