Open AccessFive-Year Cohort Study of Nosema spp. in Germany: Does Climate Shape Virulence and Assertiveness of Nosema ceranae ?
Author(s) -
Sebastian Gisder,
Kati Hedtke,
Nadine Möckel,
Marie-Charlotte Frielitz,
Andreas Linde,
Elke Genersch
Publication year - 2010
Publication title -
applied and environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.552
H-Index - 324
eISSN - 1070-6291
pISSN - 0099-2240
DOI - 10.1128/aem.03097-09
Subject(s) - nosema ceranae , biology , microsporidia , nosema , spore , population , microbiology and biotechnology , virulence , pathogen , veterinary medicine , genetics , medicine , demography , sociology , gene
Nosema ceranae andNosema apis are two fungal pathogens belonging to the phylum Microsporidia and infecting the European honeybee,Apis mellifera . Recent studies have suggested thatN. ceranae is more virulent thanN. apis both at the individual insect level and at the colony level. Severe colony losses could be attributed toN. ceranae infections, and an unusual form of nosemosis is caused by this pathogen. In the present study, data from a 5-year cohort study of the prevalence ofNosema spp. in Germany, involving about 220 honeybee colonies and a total of 1,997 samples collected from these colonies each spring and autumn and analyzed via species-specific PCR-restriction fragment length polymorphism (RFLP), are described. Statistical analysis of the data revealed no relation between colony mortality and detectable levels of infection withN. ceranae orN. apis . In addition,N. apis is still more prevalent thanN. ceranae in the cohort of the German bee population that was analyzed. A possible explanation for these findings could be the marked decrease in spore germination that was observed after even a short exposure to low temperatures (+4°C) forN. ceranae only. Reduced or inhibitedN. ceranae spore germination at low temperatures should hamper the infectivity and spread of this pathogen in climatic regions characterized by a rather cold winter season.