Morel needs help investigating the mushroom that grows on Parasect's back.
The Request
Check on the blackboard in Professor Laventon's office in Galaxy Hall in Jubilife Village to accept this request.
Talk to Morel
Talk to Morel in Jubilife Village to proceed.
Catch a Parasect
Parasect can be found in all areas except Alabaster Icelands. You will need to give Morel a Parasect, so you might want to catch more than one so you still have one for yourself.
Reward
You will get 5 Candy Truffles after you give Morel a Parasect.