Hi all!

I had an old (cca. 10 years old) tomato seed (Prisca F1). I tried to bed
it. After it sprouted, it grew good. Yet it is ~40 cm tall, and lost
many leaves. Its leaves becomes thin and hard, and dry up. And last 2
days all leaves started to fade.
What is the reason, and how can I rescue this plant?
Many thanks!

(P.s.: sorry, my english is bad, but I hope, you can understand it.)