MUMMY BERRY INFECTION PERIODS HAVE NOT YET OCCURRED YET.

WALDO, KNOX, LINCOLN
Mon. April 18th- A single mummy berry cup was present near Union, and many pinhead cups (not yet producing spores) were present in Union and Liberty areas. Plants do not yet have enough open flower and leaf buds to have susceptible tissue to be infected. The rain predicted for Wednesday may cause an infection period IF you have an early field that already has 40% of the stems with opening flower buds (stage F2). See below on how to determine the plants' stages in your field.

DOWNEAST
Mummy berries are starting to germinate in a few areas but are only at the pinhead stage (too early to produce cups). Plants do not yet have enough open flower and leaf buds to have susceptible tissue to be infected.

HOW TO CHECK PLANT STAGE IN YOUR FIELD
Please check your fields to see if 40% of the stems (8 out of 20 stems) have flower buds at the F2 stage (seen to your right). Walk across your field and randomly collect 20 stems. If 8 out of 20 stems have flower buds at F2 stage than your plants are far enough along to become infected. Flower and leaf bud development follow each other closely and flower buds are much easier to determine when they are susceptible.

Please follow all recommendations in Disease Control Guide for 2011, Bulletin 219.

FROST is NOT required for mummy berry infection
Studies in Nova Scotia by Dr. Paul Hildebrand have found that plants do NOT need to have been exposed to frost to get mummy berry infections. The fungal spores only need susceptible leaf or flower tissue and a long enough wet period (dependent on the temperature) to get into the plant. Leaves and flowers exposed to frost have more severe disease symptoms but no more infections than without frost. Disease will occur after an infection period even if no frost has occurred.

Request for information on YOUR mummy berry plots
IF you have mummy berry plot you are watching, please call (1-800-897-0757) or email (sannis@maine.edu) and tell me where your location is and what stage are your mummy berries. I would very much appreciate any additional information.