Small hive beetle (Aethina tumida Murray, 1867) (SHB) is one of the important pests of bee keeping industry. This species is endemic in sub-Saharan region of Africa that has recently became an invasive and distributing rapidly throughout the world. Recent detections of SHB in Philippines, Brazil and South Korea indicate that SHB has the potential to become a global pest for apiculture and wild bees. Having enough knowledge about the population source of invasion can help understand the pest ecology and develop the control tactics. SHB has invaded to South Korea in 2017 and cause heavy damage to apiaries in Miryang City, in south-eastern part of Korea and the origin of this pest is still unknown. The aim of this study is to evaluate the phylogenetic position and origin of Korean population of SHB. We sampled the SHB from different bee hives in Miryang city and used 922 bp part of cytochrome oxidase subunit 1 (CO1) region of mitochondrial DNA to compare with all previously reported COI sequences of SHB. The result showed that the population of SHB in south Korea is classified with South Africa, Zimbabwe, Madagascar, Canada, Australia and USA populations in one clade and among them, the lowest genetic distance between South Korean and USA populations indicated that most likely the SHB was imported from the United states to South Korea. No genetic difference has been detected between studied sequences from Korean population indicating that the invasion would had happen in one occasion.

The black soldier fly (BSF), Hermetia illucens, is known as a beneficial insect and feeds on organic materials derived from animals and human, resulting in reduction of food waste and conversion of organic materials. Despite of many studies on the BSF, there have been no reports of cloned genes encoding serine proteases in the BSF. Thus, the primary objective of this study is to clone and to investigate expression pattern of genes encoding serine proteases released from the midgut of the BSF larvae in order to gain a better understanding of expression mechanism of serine proteases. We cloned two serine proteases from the BSF larva. Based on phylogenetic tree analysis, one was chymotrypsin, the other was trypsin. The open reading frame (ORF) of chymotrypsin was 804bp, which encoded a polypeptide of 267 amino acids. In case of trypsin, the ORF was 744bp, which encoded a polypeptide of 247 amino acids. To investigate expression pattern of two serine proteases, we conducted semi-quantitative RT-PCR at different tissues and different developmental stages. A chymotrypsin and trypsin transcripts were revealed strongly in mid gut. Especially, a chymotrypsin was detected largely at feeding stage more than molting stage, while trypsin was expressed similarly between feeding stage and molting stage

The black soldier fly (BSF), Hermetia illucens, is known as a beneficial insect and feeds on organic materials derived from animals and human, resulting in reduction of food waste and conversion of organic materials. Despite of a lot of study about the BSF, there is a less information about composition of digestive enzyme of the BSF larva. Experimentally, there is no evidence about characterization of digestive enzyme of the BSF. We investigated biochemical property of digestive enzyme released from the salivary and gut of the BSF. Through digestive enzyme assay, we found that the BSF has amylase, lipase and protease activity in gut extracts, resulting in that the BSF belong to polyphagous insect group. In the BSF gut, trypsin-like protease activity showed one peak at various temperature and pH condition. This result means the BSF has probably a similar form of trypsin-like enzymes. On study of comparison of enzyme activity between the BSF and the housefly using the apiZYM kit, the BSF had more strongly digestive enzyme activity than one of the housefly about leucine arylamidase, alpha-galactosidase, beta-galactosidase, alpha-mannosidase and alpha-fucosidase. This finding supports that the BSF can ingest raw waste far more efficiently than any other known species of fly as reported previously.