Varroa destructor and Tropilaelaps mercedesae mites are ectoparasitic to honey bee having similar life cycle and damage symptoms. Both invade into the last instar larval cell and reproduce during capped brood period of honey bee development. Female adult mites escape from the comb cell on the back of the emerging adult bee (phoretic period) and invade another cell for reproduction. Objective of this study was to study the effect of competitive interaction on each parasitic mite species population. We assessed population monitoring of host and parasitic mites. Honey bee population was monitored by approximating sealed brood and adult bees based on the coverage of the combs. Parasitic mites were monitored by detection technique like sugar shake, stick board, and sealed brood. This monitoring continued at weekly interval during 2008, 2014, and 2015. Additionally Invasion distribution of each species was checked. We calculated carrying capacity, population growth rate, and competition parameter from population monitoring data. Single parasitic mite, Varroa occurred and infestation increased continuously throughout the year in 2008. Co-occurrence of Varroa and Tropilaelaps in honey bee colonies was studied in 2014 and 2015. Carrying capacity was higher in single parasite infesting honeybee than parasites in co-occurrence. While using sugar method, carrying capacity of Varroa alone was found higher than in its co-occurrence with Tropilaelaps. Population growth rate of Varroa when tested alone was higher than its co-occurrence with Tropilaelaps in sugar method. Population growth rate of Varroa and Tropilaepas was higher in sticky method than sugar methods when they were tested in co-occurrence. Population growth rate is higher in Tropilaelaps (0.09) than Varroa (0.05) when both are tested in co-occurrence. We calculated competition parameter of Varroa and Tropilaelaps which was 1.9 and 0.53, respectively. Negative effect on regulation of carrying capacity and population growth rate is due to interspecies competition. Varroa population was higher than Tropilaelaps because there was high intraspecies competition among Tropilaelaps. Single Varroa or its co-occurrence with Tropilaelaps both can destroy honeybee colonies.

Bethylidae is the largest family of Chrysidoidea (Hymenoptera: Aculeata) and distributed widely from the tropics to the subarctic regions around the world. Most members of the family are relatively small, and are generally known as ectoparasitoids of immature stages of Lepidoptera and Coleoptera. Some species have been used and studied as natural enemies of various insect pests in some countries. Even though the family Bethylidae is important group as natural enemies in the agricultural and forestry fields, fundamental researches on this group such as a faunal study have not carried out and poorly known in Korea. Since 2005, we have carried out the faunal investigation of Korean Bethylidae and more than 1,600 specimens were collected by 2010, with some of their host insects. As results of present study, fifty two species belongs to sixteen genera of Bethylidae are recognized in Korea, including seven previously recorded species as of 2006. We will introduce on the biodiversity of Korean Bethylidae and its applied aspects as potential biocontrol agents against various insect pests with cases of their usages.

As an natural enemy against the Monochamus alternatus Hope and M. saltuarius Gebler (Coleoptera: Cerambycidae), the vector species of the pine wood nematode (Bursaphelenchus xylophilus (Steiner & Buhrer), Dastarcus helophoroides (Fairmaire) (Coleoptera: Bothrideridae) is recognized for the first time in Korea. The family Bothrideridae is also reported for the first time in Korea. We provide the diagnosis, illustrations, biological information, and the host insects of D. helophoroides (Fairmaire).