The Maryblyt Prediction System for Identifying Fire Blight Infection (Erwinia Amylovora) in Fruit-Bearing Trees – Seeds in the Tirana Region

Abstract

Fire blight caused by the bacterium Erwinia amylovora is the most significant, serious, and complex disease affecting pome fruit trees. E. amylovora is considered one of the most dangerous diseases of pome fruit trees worldwide. Currently, legal and quarantine measures are in place to prevent the introduction and spread of infected propagating and planting material by E. amylovora. This research aims at the integrated management of fire blight through a combination of chemical and mechanical measures applied at critical stages of host plant infection, utilizing the Maryblyt forecasting program. The application of the Maryblyt system for determining infection risk periods is calculated based on degree days (DD) above 12.7°C, which is considered the lowest threshold for pathogen development. Examination of overwintering canker status revealed that the active inoculum was activated at the margins of softened tissues of these cankers when 59.2°C (DD) above 12.7°C had accumulated from the green tip stage. Blossom symptoms appeared when 98.3°C (DD) above 12.7°C had accumulated from the green tip stage. Shoot symptoms appeared when 158.8°C (DD) above 12.7°C had accumulated from the green tip stage. These are the potential infection periods, which enable timely treatment planning and help avoid unnecessary treatments.