Korean horn beetles, Allomyrina dichotoma (Linnaeus, 1771) reared in many local farms are suffering from a fatal viral disease as reported in 2015, and recent sequencing analysis revealed that the virus is very closely related to Oryctes rhinoceros nudivirus. In a nationwide investigation, it was concluded that the virus can transmit vertically from an infected adult to the offspring by indirect manner, and 70 to 77% of young larvae dead in early stage were diagnosed as this virus positive. Here, we report for the establishment of on-site diagnosis method for the viral disease using loop-mediated isothermal amplification (LAMP) assay. A. dichotoma larvae were assayed for the OrNV infectivity with LAMP primers targeting OrNV_gp102 gene. To evaluate the LAMP specificity, two bacterial pathogens, Bacillus thuringiensis and Serratia marcescens, causing disease in A. dichotoma were tested along with OrNV. Only from the OrNV-infected larvae the reaction resulted positive. Also, to avoid DNA extraction process, the LAMP assay used diluted hemolymph directly and 50-fold dilution was set for diagnosis standardization and convenient on-site application for infected larvae from local farms. The LAMP diagnosis is fast and convenient for nontechnical user in the field and expected to stop this foreign virus spread all over the country.

The Korean rhinoceros beetle, Allomyrina dichotoma (Coleoptera: Scarabaeidae), has been traditionally used for the treatment of liverrelated diseases. Recently A. dichotoma was registered as a food ingredient in Korea. Given the increasing interest in this beetle, studies on the development of safe and nutritious feed sources for its commercial production are needed. In this study, we compared the effects of by-products on the growth of third instar larvae of A. dichotoma. An abundance of food by-products have been found to serve as an alternative energy source in animal feeds with the reduced cost. We fed third instar A. dichotoma larvae feeds consisting of fermented sawdust with nine different combinations of citrus peel, soybean curd cake, soybean oil meal, and brewers’ dried grain, and measured their effects on growth until the larvae pupated. The highest survival rate was in feed supplemented with 10% of brewers’ dried grain (66.7%). Especially, larvae fed on 10% of brewers’ dried grain were 26% heavier than the control (with no supplement). For the group of 10% brewers’ dried grain, the larval period of third instar was shortened by almost 28 days compared to the control group. Of the experimental and control groups, only the group of 10% brewers’ dried grain showed more than 90% of pupation rate. Therefore, brewers’ dried grain may be sufficiently useful as a source of feed for A. dichotoma.