Fire blight is a destructive and highly infectious disease of apple, pear and other rosaceous plants caused by bacterial agent, Erwinia amylovora. The name of the disease is derived from the characteristic dark discoloration of affected plant tissues, as if they were burnt. E. amylovora cells are usually disseminated by insects (Aphids, plantbugs, honeybees and etc.), rain, wind or wind-driven rain (as aerosols) to open blossoms, and also to shoot, tender leaves and fruits. As wide insect domain, avoiding honey bee transport, cannot be useful and this subject, make its control difficult. Recent studies, demonstrated bacterial agent cannot survive on honey, pollen, wax and Propolis in hive condition. Therefore honeybee colonies cannot be an infection source to next spring, and preventing hives transport,would of invest wasting and low pollination of different crops is some main disadvantages that can be mentioned. It can be added that honeybees are also important in transporting useful and antagonist bacteria in infect orchards for biological control of fire blight disease. |