Reactive oxygen species (ROS) is toxic to living organisms, because its high reactivity causes oxidative damage to proteins, nucleic acids, and lipids. Superoxide dismutase (SOD) is an enzyme facilitating the removal of superoxide anions from living organisms. This study focused on the cloning of MnSOD cDNA from Hyphantria cunea and its induction upon bacterial infection and various stresses. The open reading frame of MnSOD is composed of 645 bp, encoding 215 amino acid residues. The theoretical molecular mass and pI of putative MnSOD was evaluated to be 24276 Da and 9.14, respectively. The MnSOD from H. cunea is highly similar to human MnSOD (59.5%) as well as Bombyx mori MnSOD (76.2%). MnSOD showed no big induction upon bacterial infection and stresses, compared to that of Cu/ZnSOD.

Apolipophorin-Ⅲ (apoLp-Ⅲ) is a hemolymph protein whose function is to facilitate lipid transport in an aqueous medium in insect. Recently, apolipophorin-Ⅲ in Galleria mellonella and Hyphantria cunea was shown to play an unexpected role in insect immune activation. We show here a novel possible function/role of apoLp-Ⅲ in insects. To investigate the genes which have a relationship with apoLp-Ⅲ in fall webworm larvae, we reduction of endogenous Hc apoLp-Ⅲ mRNA levels in larvae via RNA interference (RNAi). The RNAi-mediated Hc apoLp-Ⅲ reduction resulted in the reduction of antioxidants, like MnSOD, catalase, and glutathione S transferase as well as immune proteins. In particular, expression of MnSOD commonly decreased in fat body, midgut, and hemocytes following the knockdown of Hc apoLp-Ⅲ, which induced an elevated level of superoxide anion in H. cunea larvae. The observed effect of Hc apoLp-Ⅲ RNAi suggests that Hc apoLp-Ⅲ is related to the action/expression of antioxidants.

Innate immunity responses are triggered by the immune challenge and therefore involve signaling processes. The cellular response is initiated by hemocytes and mainly involves phagocytosis and encapsulation of intruders by these cells. To address whether Hc-STAT is activated upon bacterial challenge, we examined the subcellular location of STAT protein in hemocyte by immunostaining. A new insect member of the STAT family of transcription factors (Hc-STAT) has been cloned from the lepidopteran, Hyphantria cunea. The domain involved in DNA interaction and the SH2 domain are well conserved. The gene is transcribed at a low level during all stages of development, and the protein is present in hemocytes, fat body, midgut, epidermis, and Malphigian tuble (Mt). Especially, hemocytes and Mt showed transcriptional activation of Hc-STAT upon Gram (-) bacteria and fungal challenge. Gram (-) bacteria and fungal challenge specifically results in nuclear translocation of Hc-STAT protein and induction of DNA-binding activity that recognizes a STAT target site in H. cunea hemocyte. In vitro treatment with pervanadate translocates Hc-STAT to the nucleus in hemocyte cells. Here we report the first evidence for the involvement hemocyte JAK/STAT pathway upon microbial infection in lepidopteran insect.

After treatment with imidacloprid, there were clear differences in the time to the first reaction of Myzus persicae among the concentrations treated. The time taken for the proboscis of the aphids to penetrate, during the recording plants increased as the imidacloprid concentration increased. Imidacloprid concentration inflow into a leaf was investigated using high-performance liquid chromatography, and the residues of the imidacloprid varied slightly with the different concentrations treated. However, the inflow rates of this insecticide into a leaf increased as the dipping times increased. Furthermore, it was shown that there was no relationship in inflow concentration between the concentrations and times of treatment. However, the concentration in the leaf differed according to the dipping time. Judging from the fact that the first reaction behavior against imidacloprid displayed at an inflow concentration of 0.32-0.35 ㎎/L, we concluded that inflow concentrations causing the first reaction of the aphids to the insecticide were much lower than the concentration treated. The general feeding characteristics of the aphids indicated that xylem and/or phloem feeding behavior continued after a series of probing behaviors and stylet activity during the first 3 h from the start of EPG recording. After 90 min treatment with imidacloprid, feeding behavior over the next 30 min indicated a significant increase in the withdrawal of the stylet from the plant at all treated concentrations. Xylem and/or phloem feeding patterns were significantly decreased during this time. In particular, the proportion of xylem feeding differed according to the concentration of imidacloprid.

As indigenous aphid parasitoid, Aphelinus varipes kill aphids for feeding in addition to parasitization. Because of this characteristic of A. varipes, this parasitoid may have the possibility of biological control agent against aphids. So we have evaluated traits such as daily paratization, total parasization, number of aphids killed by host feeding, sex ratio, development time, pupal mortality of A. varipes parasitizing green peach aphid, Myzus persicae. At 25°C and 16L:8D, longevity, total paratization and host feeding of A. varipes female was 11.0, 25.3, and 63.3 days, respectively. And development time of male and female, sex ratio (M:F), pupa mortality of offspring of A. varipes were 12.0 days, 12.5 days, 0.88, and 11.6%, respectively. However, because these results are not enough to estimate potential of A. varipes as biological control agents/factors, other factors such as host suitability (Macrosiphum euphorbiae, Aulacorthum solani), effect of temperature, and host seeking behavior of A. varipes continually will be investigated.

Reactive oxygen species (ROS) is toxic to living organisms, because its high reactivity causes oxidative damage to proteins, nucleic acids, and lipids. Superoxide dismutase (SOD) is an enzyme facilitating the removal of superoxide anions from living organisms. This study focused on the cloning of MnSOD cDNA from Hyphantria cuneaand its induction upon bacterial infection and various stresses. The open reading frame of MnSOD is composed of 645 bp, encoding 215 amino acid residues. The theoretical molecular mass and pI of putative MnSOD was evaluated to be 24276 Da and 9.14, respectively. The MnSOD from H. cunea is highly similar to human MnSOD (59.5%) as well as Bombyx mori MnSOD (76.2%). MnSOD showed no big induction upon bacterial infection and stresses, compared to that of Cu/ZnSOD.

Innate immunity responses are triggered by the immune challenge and therefore involve signaling processes. The cellular response is initiated by hemocytes and mainly involves phagocytosis and encapsulation of intruders by these cells. To address whether Hc-STAT is activated upon bacterial challenge, we examined the subcellular location of STAT protein in hemocyte by immunostaining. A new insect member of the STAT family of transcription factors (Hc-STAT) has been cloned from the lepidopteran, Hyphantria cunea. The domain involved in DNA interaction and the SH2 domain are well conserved. The gene is transcribed at a low level during all stages of development, and the protein is present in hemocytes, fat body, midgut, epidermis, and Malphigian tuble (Mt). Especially, hemocytes and Mt showed transcriptional activation of Hc-STAT upon Gram (-) bacteria and fungal challenge. Gram (-) bacteria and fungal challenge specifically results in nuclear translocation of Hc-STAT protein and induction of DNA-binding activity that recognizes a STAT target site in H. cunea hemocyte. In vitro treatment with pervanadate translocates Hc-STAT to the nucleus in hemocyte cells. Here we report the first evidence for the involvement hemocyte JAK/STAT pathway upon microbial infection in lepidopteran insect.

As an effective generalist predator of aphids and other hemipteran pests, Harmonia axyridis has been a successful biological control agent. Interestingly, it was known that there were varied in color patterns on H. axyridis elytra. In fact, Seo & Youn (2007) reported that H. axyridis had five color patterns, for example, succinea 1, 2, conspicua, spectabilis, and axyridis. But there are uncertain that H. axyridis elytra colour patterns are regulated by genetic polymorphism. So we tried to what is the reason that color patterns are greatly variable. To identify DNA markers linked to a elytra polymorphism, amplified fragment length polymorphism (AFLP) analysis was performed on DNA samples from four female succinea, conspicua, spectabilis and Coccinella septempunctata which is another species in Coccinellidae. AFLP analysis with the restriction endonuclease combination EcoRⅠ and MseⅠwas performed. Using 12 AFLP primer pairs, nine AFLP fragments which is specific between succinea, conspicua, spectabilis was identified. These nine AFLP fragments were isolated, cloned and sequenced. Subsequent UPGMA cluster analysis revealed three major group of H. axyridis populations. These genetic tree showed that H. axyridis elytra colour diversity was affected by genetic polymorphism. For more genetically understanding elytra colour genes, different primer combinations may be need to be generate enough polymorphic markers. These genetic analyses may be facilitate the understanding of molecular mechanism behind wing colour pattern formation.

The surface of most coccinellids (particularly the elytra) has characteristic colour patterns, which show great variability within many species. Individuals of a species of ladybird often differ from one another in colour and pattern. In case of Harmonia axyridis, environmental factors, such as temperature or food, can probably influence colour and pattern. However, virtually no work has been carried out in the influence of such factor. Therefore, in this study, according to rearing temperature, photoperiod and diet, variation of elytra color patterns were investigated. First instar larva on each color pattern were reared in an incubator at one of two temperatures; 25 and 30℃, under the following photoperiod; L16: D8, L12: D12 and L8: D16 and were provided three species of aphids. And their color pattern of adults were estimated.

The multicolored Asian ladybird beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), is common to a wide range of natural and agricultural habitats. Applications of gamma irradiation minimized the losses of stored food and the death or failure of emergence in larval and pupal stages. On the other hand, degrade toxin waste as one of alternative to chemical pesticide for both quarantine and sprout control purposes of storage crop pest. So, we have investigated whether gamma irradiation exposed to eggs, lava, pupa and adults of H. axyridis. It may be affected the emergence, fertility, fecundity, development period and sex ratio of H. axyridis. Some changes of physiological characteristics may be applied to more efficient agents as biological control of several aphids. Insects were exposed to gamma irradiation from 0 to 500 Gy of 60Co depended on their developmental stages. The results showed that the first instar, eggs, third instar, pupae, and adults were more sensitive in order of irradiation dose. And fecundity and fertility of female adults were significantly decreased with increasing gamma irradiation dose at all tested individuals.

The multicolored Asian ladybird beetle, Harmonia axyridis, which demonstrates typical genetic polymorphism in its elytra color patterns. Early studies have color polymorphism in terms of geographical clines while a few investigated temporal populations in Coccinellidae. Nevertheless, note that geographical and temporal morph variation does not always correspond to what is expected from thermal and industrial adaption theories. A recent study of transformation and RNAi of the ladybird beetle, however, there is yet no evidence to indicate the variation is genetic or environmental factors. Here we describe a relatively new molecular fingerprinting technique, amplified fragment length polymorphism (AFLP). Because we think that color polymorphism in Coccinellidae is affected by genetic polymorphism. In total 38 markers were scored from which some markers were polymorphic. Supsequent UPGMA cluster analysis revealed 3 major group of Harmonia axyridis populations. But for strains that are more genetically similar, different primer combinations may be need to generate enough polymorphic marker.