EN
Nosemosis is serious and widespread bee disease connected with Collony Colapse Disorder (CCD). Monitoring of this disease is crucial to a better understanding of the effect of this disease on the health in both individual bees and at the whole colony level. There is little information about nosemosis in different parts of Poland, which have distinct beekeeping management and climate conditions. It is also important to have quick and easy methods of differentiation of the type of nosemosis (type A - caused by Nosema apis and C - by N. ceranae). Therefore the aims of the study was to determine the degree of Nosema spp. infection amount in the Lublin region during the course of 7 years and to find morphometric parameters which could help to distinguish the differences between spores of N. apis and N. ceranae. In the Lublin region the amount of nosemosis infection has risen from the year 2001 to 2008, with the highest infection scores in 2008. This decreasing number of healthy colonies probably provides evidence of the impact of the greater frequency of N. ceranae infection, which could be the one of the causes of CCD. Scanning Electron Microscopy (SEM) reveals that N. apis and N. ceranae spores differ in their surface structure. Generally, spores of N. ceranae seemed to be more sculptured with deeper ornamentation than those of N. apis. Therefore ornamentation of the spores cell walls with special reference to their area can be considered as a taxonomic criterion for separating these two Nosema taxa.