I

ANNO 3 Numero 2
Emanuele Carpana [1], Maia Alexandrova[1,2], Carlo Bazzi [2], Claudio Porrini [2], Sergio Massi [1], Alessandra Ferro [1], Anna Gloria Sabatini [1]

Longevity of Erwinia amylovora in honeybees (Apis mellifera), bee hives and hive products

[1] CRA - Istituto Nazionale di Apicoltura , Bologna, Italy
[2] DISTA - Area Entomologia, Università di Bologna, Italy

Corresponding author: ecarpana@inapicoltura.org


Erwinia amylovora (Burrill) Winslow et al. is the bacterium responsible for fire blight, the most destructive disease of pome fruit trees and rosaceous plants. Honeybees are known to spread the bacterium.

This study, conducted in 1999-2000, investigated the longevity of E. amylovora on the bodies of bees, in their alimentary tracts and in beehive products (honey, beeswax, pollen and propolis) at different temperatures.

Persistence of the bacterium in hives kept outdoors was also determined. In the laboratory experiments, E. amylovora did not survive more than two days on the surface of the bees’ body. Longevity in honey varied from a maximum of six weeks at 4°C to 1 day at 35°C. In beeswax, the maximum longevity was three weeks at both 4°C and 15°C and the minimum was less than four days at 35°C. In corbicular pollen, persistence of the bacteria exceeded 30 weeks at both 4 and 15°C, while at 28 and 35°C survival was less than three days. In propolis, no viable bacteria were detected six hours after inoculation. In hives kept outdoors the bacterial longevity measured in spring and autumn was less than 72 h in pollen and up to 48 h in the other hive products.