Nosema is an important disease that negatively affects bees' performance by disrupting the digestive system of bees. The disease, which is known to be widespread in almost every part of the world except Central Africa, is a highly dangerous fungal infection for honey bees, which occurs with infection of honey bees' ventricular epithelial cells by Nosema apis and Nosema ceranae. Nosema infection, one of the most common diseases in honey bees, is more dangerous due to the adverse effects of the factor itself and secondary infections. It is one of the most important causes of honey bee colony losses. This study aimed to investigate the effectiveness levels of essential etheric oils against nosema infection. 21 colonies obtained from Ordu Region, equalized physiologically and divided into 7 groups. Nettle, laurel, eucalyptus, thyme, garlic oils (after dilution of 0.48%), and apple cider vinegar were given to each colony 6 times at 3 days intervals of 3 mL/L to 1:1 ratio syrup (prepared for each separate group). Adult bee samples were taken from all colonies before each additional feeding, and nosema spore counts were performed.At the end of the study, plants' effect against nosema infection and plant X application time interaction effect were found insignificant, and the difference between application times was found significant. Although essential oils used in the study reduced nosema spores, it was shown that there was no definite result in terms of the treatment of the disease.

Purpose Bumblebees are an important group of insects in the pollination of various vegetables, fruits, oilseeds, legumes, and the fodder crops. Compared to honeybees, they have a wider choice of hosts and a longer flight period. These bees are used especially for the pollination of plants in greenhouses and are commercially produced for this purpose. Recently, serious decreases have been occurring in bumblebee populations due to various reasons such as pathogens and parasites, and some of species are even threatened with extinction. In this study, the presence of various pathogens and parasites was investigated by PCR in Turkish populations. Methods A total of 172 Bombus terrestris (Linnaeus,1758) samples (21 samples from commercial enterprises, 79 samples from greenhouses and 72 samples from nature) collected from three provinces (Antalya, Mersin and İzmir) where greenhouse cultivation is intensively carried out in Turkey. 89 of these samples were collected in the spring and 83 in the fall. Results The overall prevalence of Nosema bombi, Crithidia bombi, Apicyctis bombi and Locustacarus buchneri was determined as 7.55%, 9.3%, 11.62% and 4.65%, respectively. Co-infections (5.81%) were only detected in nature samples. C. bombi and A. bombi infections were detected at higher rates in the spring samples than the autumn samples (p < 0.05). Conclusion The obtained results could be important in determining the spread rates of the bumblebee diseases in Turkey and in the control of these diseases. More studies are needed to determine the transmission pathways of these pathogens between the populations.