Nabian et al.: First Detection of Nosema ceranae … verse sequences were compared with those of related species obtained from Gen Bank. Diagnosis was confirmed with the sequences obtained, which corresponded to N .ceranae. All the samples analyzed were positive for N. ceranae, clearly showing its current pres- ence in this region. Blast search against Gen Bank revealed the highest similarity (99.8 or 100%) with N.ceranae 16SrRNA partial sequence. In all of the samples analyzed, the presence of N. ceranae was detected (Fig. 2). All six positive and three negative controls, tested 3 times showed the same results which dem- onstrated the reliability of the method. The expected PCR products 218bp for N. ceranae are observed. Our results showed that N. ceranae was detected in all six mac- erated abdomens of adult honeybees. The presence of N. ceranae in Iran was verified. Fig.1: The presence of Nosema spore, (wet mount, 400X) in macerated abdomens sus- pension of adult honeybees 92 Fig. 2: PCR analysis of extracted DNA from Nosema spore using primers ( 218 MITOC) specific for Nosema ceranae derived from 16 SrRNA of the protozoa( Lane 1-6), and the negative controls (TO1-3) Discussion During the last 10 years, an increase in in- fections by microsporidian parasites in the honeybee (A. mellifera) has been detected in several European countries (2-4), while in- creasing numbers of honeybee colony death and low production in the same areas have been reported by beekeepers. One of the principal hypotheses that might explain these problems is the recent entry and rapid dis- semination of N. ceranae in Europe (16). The most significant difference between the two types of Nosema (N. ceranae and N. apis) is how quickly N. ceranae can cause a colony to die. Bees can die within 8 days after exposure to N. ceranae, which is faster than bees exposed to N. apis. The foraging force seems to be affected the most. They leave the colony and are too weak to return, thus dying in the field. Former reports of the distribution of Nosema disease in Iran (20, 21), assumed that only