Botrytis Neck Rot in Maine Garlic (PDF) Developed by Steven B. Johnson, Extension Crops Specialist, and David Fuller, Extension Professional For information about UMaine Extension programs and resources, visit extension.umaine.edu. Find more of our publications and books at extension.umaine.edu/publications/. Botryotinia (Botrytis) porri is the fungal pathogen that causes neck rot in garlic. This is a