Rear Fender Molding
 

Recently found that a portion of the molding (if I’m correct) was broken off. Anyone familiar with its purpose? Do I need to cover up this area with sealer?
http://i65.tinypic.com/xbbn6u.jpg
http://i63.tinypic.com/1xz9nb.jpg

It's a thick bead of seam sealer that was painted from the factory. It exists to prevent water, mud and grime from getting between the panels and eventually rusting out your quarter panel.

Thank you so much. Any product recommendations to replace the section? I was going to go with the 3M seam sealer.