How are parasitic fungi different from other fungal symbionts?

Explanation:

In contrast to other fungi symbionts for example: saprotrophic fungi, parasitic fungi attack living organisms, they invade them, penetrate their outer defense mechanism and take nourishment from the cytoplasm of living things and cause disease which may result to death of the host. Most disease causing or pathogenic fungi are parasitic to plants.

(nitrogen fixation) will be your answer sorry if im wrong