• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.57-62
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• 2007

Reproductive incompatibility is an Important factor to select a specific biologlcal control agent for successful augmentation of the corresponding endogenous population. An endoparasitoid, Cotesia plutellae (Kurdjumov), is an effective control agent to diamondback moth, Plutella xylostella (L.) and has been known to be classified into two groups in terms of reproductive incompatibility. This study analyzed an Korean population of C. plutellae in terms of morphological characters and mitochondrial DNA marker, which did not match with either of two reproductive incompatibility groups. These results suggest that a Korean population of C. plutellae can be involved in a novel reproductive group. For any augmentation program of C. plutellae in Korea, reproductive incompatibility should be seriously considered to select a particular exotic population.

• Animal Systematics, Evolution and Diversity
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• v.25 no.1
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• pp.65-80
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• 2009

Pyrgotidae is a small acalyptrate family including about 370 species worldwide and little attention has been given to their systematics until recently. Latest changes in taxonomic status of some of the Korean species made this review inevitable. In the present study, the Korean pyrgotid species are reviewed with discussion of their taxonomic status. We also provide a revised key to all 14 Korean species (seven Adapsilia, three Eupyrgota, two Parageloemyia, one Porpomastix, and one Tephritopyrgota species) supplemented by digital images to facilitate accurate identification.

• Journal of Forest and Environmental Science
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• v.14 no.1
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• pp.128-137
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• 1998

In Fukuoka, the natural enemies of Protopulvinaria mangiferae were confirmed as six primary parasitoids, three hyperparasitoids, and six predators. Among the primary parasitoids, Aneristus ceroplastae, Microterys flavus, and Coccophagus yoshidae were relatively abundant in Fukuoka. Aneristus ceroplastae and Coccophagus yoshidae were solitary endoparasitoid, whereas Microterys flavus was a gregarious endoparasitoid. Tetrastichus sp. was a hyperparasitoid and solitarily ectoparasitic to the pupae of Aneristus ceroplastae and Microterys flavus. The seasonal fluctuation of parasitisim and adult emergence of the important parasitoids was investigated in Fukuoka. Among the predatorys, Rhyzobius forestieri and Chilocorus kuwanae were relatively abundant, and seasonal fluctuation of adult emergence and consumption of the host were studied. As the first record from Japan, Rhyzobius forestieri was collected on leaves of Elaeocarpus sylvestris with heavy infestation of Protopulvinaria mangiferae.

• BMB Reports
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• v.41 no.5
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• pp.388-393
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• 2008

The Pphsc70 (heat shock cognate 70) gene was isolated from the endoparasitoid Pteromalus puparum and then characterized. The full-length cDNA was 2204 base pair (bp) and contained a single 1968 bp ORF that encoded a polypeptide of 656 amino acids with a predicted molecular mass of 71.28 kDa. Phylogenetic analysis based on Hsc70 amino acid sequences from fifteen insect species agreed with the present phylogeny. In addition, genomic DNA confirmed the presence of three introns located at the coding region as well as the 5'UTR. A significant elevation of Pphsc70 expression was observed following heat treatment, however, continued exposure to heat shock or recovery caused the expression of induced mRNA to gradually decline to levels that were significantly lower than those of control pupae (P < 0.05). In addition, a significant increase was observed in the emergence rate of pupae that were preheated at $40^{\circ}C$ and then exposed to $50^{\circ}C$ for 1 h when compared with the pupae that were not preheated, but instead directly exposed to $50^{\circ}C$. Taken together, these results revealed that exposure to gradually increasing temperatures can enhance an insects thermo-tolerance.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.21-26
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• 2004

These studies were carried out to investigate the oviposition and host feeding characteristics of Neochrysocharis formosa Westwood, an endoparasitoid of Liriomyza trifolii. N. formosa female oviposited inside the abdomen at the rear end of the host larva. Number of eggs and host feeding per day of N. formosa tended to increase as temperatures go up. The ratio of oviposition and host feeding of N. formosa were 0.5, 0.9, 1.0 and 1.0 at 15, 20, 25, and 30$^{\circ}C$, respectively. In 25$^{\circ}C$, number of eggs and host feeding were 176.0 and 188.7, respectively, and aduly female longevity was 11.8 days. N. formosa female preferred to the 3rd rather than 1st and 2nd larva for oviposition and host feeding.

• Animal Systematics, Evolution and Diversity
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• v.34 no.3
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• pp.159-161
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• 2018

The genus Microplitis (Braconidae: Microgastrinae) is reported for the first time from Korea. The Microplitis has often quite small hypopygium, very short ovipositor and rugose propodeum with large aleola. The genus contains 190 described species, among them 19 speceis were recorded in Korea. Microplitis varicolor was established by Viereck in 1917. The species is found as new to Korea in this study. Microplitis varicolor is endoparasitoid, especially attacking species of Noctuidae (Insecta: Lepidoptera) including pests of leguminous crop. In this study, diagnosis, photographs and host lists are included.

• BMB Reports
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• v.44 no.6
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• pp.393-398
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• 2011

Polydnaviruses are a group of double-stranded DNA viruses and are symbiotically associated with some ichneumonoid wasps. As proviruses, the replication of polydnaviruses occurs in the female reproductive organ at the pupal stage. This study analyzed the effects of two developmental hormones, juvenile hormone (JH) and ecdysteroid, on the viral replication of Cotesia plutellae bracovirus (CpBV). All 23 CpBV segments identified contained a conserved excision/rejoining site ('AGCTTT') from their proviral segments. Using quantitative real-time PCR based on this excision/rejoining site marker, initiation of CpBV replication was determined to have occurred on day 4 on the pupal stage. Pyriproxyfen, a JH agonist, significantly inhibited adult emergence of C. plutellae, whereas RH5992, an ecdysteroid agonist, had no inhibitory effect. Although RH5992 had no effect dose on adult development, it significantly accelerated viral replication. The results of immunoblotting assays against viral coat proteins support the effects of the hormone agonists on viral replication.

• Animal Systematics, Evolution and Diversity
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• v.31 no.2
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• pp.77-85
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• 2015

We reviewed South Korean species of the genus Apechthis and confirmed four species and two subspecies. In this genus, four species and one subspecies have been reported from the Eastern Palaearctic region, two species and one subspecies were from South Korea. Additionally, we report two species and one subspecies, Apechthis compunctor orientalis Kaspryan, 1973, Apechthis quadridentata (Thomson, 1877) and Apechthis rapae (Uchida, 1925), which were newly recorded for the first time from South Korea. A key to South Korean species of the genus Apechthis, redescriptions of newly recorded species and subspecies and digital images of South Korean Apechthis are provided.

• Korean journal of applied entomology
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• v.56 no.1
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• pp.19-28
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• 2017

Polydnaviruses (PDVs) are a group of double-stranded DNA viruses symbiotic to some endoparasitoid wasps. Cotesia plutellae bracovirus (CpBV) is a PDV symbiotic to an endoparasitoid wasp, C. plutellae, parasitizing young larvae of Plutella xylostella. An early expressed gene, CpBV-ELP1, plays an important role in the parasitism by suppressing host cellular immunity by its cytotoxic activity against hemocytes. This study aimed to test its oral toxicity against insect pest by expressing it in a recombinant tobacco plant. A recombinant CpBV-ELP1 protein was produced using a baculovirus expression system and secreted to cell culture medium. The cell cultured media were used to purify CpBV-ELP1 by a sequential array of purification steps: ammonium sulfate fractionation, size exclusion chromatography, and ion exchange chromatography. Purified rCpBV-ELP1 exhibited a significant cytotoxicity against Spodoptera exigua hemocytes. CpBV-ELP1 was highly toxic to the fifth instar larvae of S. exigua by injection to hemocoel. It also showed a significant oral toxicity to fifth instar larvae of S. exigua by a leaf-dipping assay. CpBV-ELP1 was cloned into pBI121 vector under CaMV 35S promoter with opaline synthase terminator. Resulting recombinant vector (pBI121-ELP1) was used to transform Agrobacterium tumefaciens LBA4404. The recombinant bacteria were then used to induce callus of a tobacco (Nicotiana tabacum Xanthi) leaves and subsequent generation (T1) plants were selected. T1 generation tobacco plants expressing CpBV-ELP1 gave significant insecticidal activities against S. exigua larvae. These results suggest that CpBV-ELP1 gene can be used to control insect pests by constructing transgenic crops.

• Korean journal of applied entomology
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• v.43 no.3 s.136
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• pp.225-231
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• 2004

An endoparasitoid wasp, Cotesia plutellae, has been used for a biological control agent against the diamondback moth, Plutellae xylostella. It has a symbiotic polydnavirus in their reproductive tract, which is required for its successful parasitization. Here, we measured a specific replication time of the polydnavirus during female development of C. plutellae. We, also, analyzed the reproductive potentials of female C. plutellae under mating or different host conditions. At $25^{\circ}C$, pupal C. plutellae began to develop adult tissues such as compound eyes and wings since day 2. At day 5, all adult tissues including antennae were developed and were ready to emerge. With polyclonal antibody raised against C. plutellae polydnavirus, an immunobloting could confirm virus replication at day 4 during pupal stage. Virus particles could be visualized by transmission electron microscope in the oviduct lumen of day 5 pupae. After adult eclosion, venom gland and ovarian calyx increased in size, though ovarioles did not. Mated females layed large number of eggs (over $60\%$) at first 4 days during their mean longevity of ca. 8 days at $25^{\circ}C$. Unmated females showed less active ovipositional behavior, where all the eggs developed into males. C. Plutellae parasitized both P. xylostella and fall webworm, Hyphantria cunea. However, C. Plutellae developed faster and showed higher successful paarasitization in P. xylostella than in H. cunea.