The α-proteobacterium Wolbachia is maternally inherited and is known to induce reproductive distortions in a wide range of insect taxa such as cytoplasmic incompatibility, feminization, male killing and parthenogenesis (PI). When a female is infected with PI-Wolbachia, she does not need a male to produce female offspring, because the female can produce female offspring via gamete duplication without the aid of sperm. However, in the parasitoid wasp Trichogramma kaykai species, Wolbachia infected parthenogenetic females still produce a fraction of male offspring. Offspring sex ratio for 10 days are different according to each T. kaykai isofemale line that is infected with PI- Wolbachia. This may be caused by complex interactions between Wolbachia and the host genetic backgrounds on converting sex of infected eggs.

A taxonomic review of the fungivorous tetratomid beetles in Korea, which comprises four species belonging to two genera of two subfamilies, is presented. Three species, Holostrophus (Paraholostrophus) orientalis Lewis, 1895 and two newly recorded species, Pisenus insignis (Reitter, 1889) and Holostrophus diversefasciatus Pic, 1921, are identified and described herein. A photograph of adults, diagnoses, illustrations of diagnostic characteristics, and ecological information regarding habitat, and host fungi are provided.

콜레마니진디벌(Aphidius colemani)은 진딧물과의 생물적 방제자로서 전세계적으로 널 리 이용되고 있으며, 경제적으로도 대단히 가치가 높은 분류군이다. 그러나 인위적으로 동일 한 숙주에서 수 세대에 걸쳐 누대사육 될 경우 이들의 형태적 유연성은 감소하고, 숙주의 생리 적 질에 따라 크기와 충질에서도 많은 차이를 나타내게 된다. 또한 숙주 선택 행동은 natal host로 부터 비롯된 표현형적 한계로 인해 제약을 받고, 공급되는 숙주의 령기 편차에 따라 기 생률은 현저한 차이를 보인다. 본 연구의 목적은 대량사육 되는 콜레마니진디벌의 도태를 방지하고 생물적 방제에 적합 한 품질을 지속적으로 유지시키기 위한 방법을 모색하는 것으로, natal host의 인위적 조절로 인해 발생하는 현상을 확인하는 것이다. 이에 본 연구에서는 서로 다른 두 natal host 종에서 발생한 콜레마니진디벌 개체군을 대상으로 이들의 크기 변화를 측정하고 복숭아혹진딧물 (Myzus persicae)에 대한 각각의 산란력, 성충 크기에 따른 숙주의 크기 선호성, 그리고 두 콜 레마니진디벌 개체군이 혼합되었을 때 생산량의 차이를 확인하였다. 온도 25℃, 상대습도 70%RH, 광조건 16L:8D에서 복숭아혹진딧물에 대한 콜레마니진 디벌의 일일산란력(eggs/1 female/1 day)을 조사한 결과, natal host가 복숭아혹진딧물인 콜 레마니진디벌은 66.4±33.9eggs, 아카시아진딧물(Aphis craccivora)인 콜레마니진디벌은 111.2±51.0eggs으로 전자보다 산란력이 높은 것으로 확인되었다. 기생자의 성충 크기에 따 른 숙주 크기 선호성에 대해 조사한 결과, 복숭아혹진딧물에서 발생한 콜레마니진디벌 개체 군의 평균 hind tibia 길이는 433.2±26.5㎛로 몸길이가 0.85±0.22㎜인 복숭아혹진딧물을 선호하였으며, 아카시아진딧물에서 발생한 콜레마니진디벌의 hind tibia 길이는 516.1±24.0 ㎛로 1.21±0.26㎜ 크기를 선호하는 것으로 나타났다. 따라서 natal host에 따라 콜레마니진 디벌의 성충 크기는 차이가 있으며, 이들의 크기와 비례하여 숙주 크기 선호성 또한 차이가 있음을 확인하였다. 이와 같은 특성을 이용하여 두 개체군이 혼합된 콜레마니진디벌을 복숭 아혹진딧물에 기생시킨 결과 0.13㎥ 크기의 사육 cage에서 55,000 마리의 콜레마니진디벌 이 생산되었으며, 이는 혼합하지 않은 두 대조군 보다 약 30% 많은 개체수로 확인되었다. 본 연구의 결과, 콜레마니진디벌의 대량 생산 체계에 있어 natal host의 인위적 변경은 콜레마 니진디벌의 생리적 특성 및 충질을 변화시켜 산란력과 생산력을 증진시킬 수 있는 중요한 요 소가 되는 것으로 판단된다.

Host plants of insect pest in turfgrass and ornamental tree, Popillia flavosellata (Coleoptera: Ruteridae) were investigated in golf courses and forest. Twenty six species in 18 families were observed to be fed on from this research and 22 species in 15 families were recorded newly host plants of P. flavosellata. Thus, total number of host plants of P. flavosellata were 49 species in 23 species. P. flavosellata adult mainly fed on flower of host plants. Seasonal prevalence of P. flavosellata adult was investigated in East Valley Country Club in Gwangju, Gyeonggii, Korea using Japanese beetle pheromone lure and a eugenol feeding attractant. Peak activity of P. flavosellata adult was nearby 20 June. Mean attracted number of P. flavosellata adult at peak day were 197.6 individuals/ trap/day at 2008 and 268.1 individuals at 2010. Occurrence of P. quadriguttata were very lower then P. flavosellata. Mean attracted number of P. quadriguttata adult at peak day were 17.5 individuals/trap/day at 2008 and 2.3 individuals at 2010 in same trap.

Alfalfa weevil, Hypera postica Gyllenhal, is regarded as one of the most important insect pests on Chinese milk vetch and hairy vetch. The insect usually feed on leaves, stems and pods of the green manure which causes severe reduction of biomass. This study was conducted to observe the occurrence of H. postica larva and adult on Chinese milk vetch in 2009 to 2010, and to evaluate host plants preference of 11 different seedlings in 2010, Milyang, Korea. Occurrence of H. postica larvae on Chinese milk vetch was observed to increase from early April clearly and its peak population was showed during middle to late April. The 1st generation of newly emerged adult of H. postica was appeared on 20th May. Newly emerged H. postica adult was fed on green manure such as Chinese milk vetch and hairy vetch as well as various seedlings located at nearby upland. And then the insects were migrated into aestivating places in middle to late of June. Thus, host plant preference of H. postica adults were evaluated with 11 different seedlings using transparent acrylcage and at Chinese milk vetch field. As a result, H. postica adult preferred on Chinese cabbage, followed by soybean, kale, foxtail millet and proso millet. The damaged rating of seedlings were shown to have the same trend with adult occurrence. In particular, few H. postica adults were occurred on eggplant, lettuce, corn, crown daisy and peanut, and thereby those crops were regarded as non-preference plants due to the absence of damage. These informations can be used by upland farmers who sowing from late May to early June for effective management of H. postica.

The α-proteobacterium Wolbachia pipientis infects a wide range of arthropods and filarial nematodes. Wolbachia is maternally inherited and is known to induce reproductive anomalies such as cytoplasmic incompatibility, feminization, male killing and parthenogenesis induction (PI). Trichogramma kaykai is a tiny wasp that parasitizes on lepidopteran eggs. When a female of the wasp is infected with PI-Wolbachia, the female produces female offspring via gamete duplication without the aid of sperm. As she ages, however, the fraction of male offspring increases. In this study, we investigated the effect of host genetic background on the expression of sex ratio between isofemale lines. Virgin females of six isofemale lines were allowed to lay eggs individually for 10 days. There was the positive relationship between female age and the offspring sex ratio. Furthermore, the sex ratio was significantly different among isofemale lines, implying that the host genetic background had an effect on the sex ratio. Based on the results, evolution of symbiosis in terms of sex ratio and future experimental design are discussed.

Cordyceps sensu lato is known as one of the largest genera in hypocrealean fungi and largest group of entomopathogenic fungi in Ascomycota. Approximately 400 species are members of Cordyceps s. l. and most of them are obligate symbionts of 10 orders of arthropods and false truffles specifically parasitizing Elaphomyces spp. Recently, Cordyceps s. l. was reclassified into Cordyceps sensu stricto, Elaphocordyceps, MetaCordyceps, and OphioCordyceps in three families (i.e., Clavicipitaceae, Cordycipitaceae, Ophiocordycipitaceae) with the evidence of recent multigene phylogenetic analyses coupled with morphological and ecological characters. With the closely related animal, plant and fungal associated genera (e.g., Balansia, Claviceps, Hypocrella and Torrubiella) of Cordyceps s. l., Cordyceps s. l. and its related genera in Hypocreales have been considered as one of the model systems in understanding the evolution of host affiliation in Kingdom Fungi. Here the overview of molecular systematic of Cordyceps was presented with its evolutionary hypotheses of host affiliation based on the ancestral state reconstruction from 162-taxon data set. In our results, the evolution of its host affiliation is largely characterized by frequent interkingdom host-jumps and ergot and grass endophytes (e.g., Balansia, Claviceps, Epichloe and Neotyphodium) are hypothesized to be derived from an ancestor that parasitized arthropods. Around 350 taxa have been included in the molecular phylogeny of Cordyceps s. l. after the new classification was proposed. Therefore, the progress and problems in current molecular phylogeny are also presented with introduction of the future research direction in molecular systematics and genomics of Cordyceps and its related genera.

The larval parasitoid, Bracon hebetor, attacks third or older larvae of indianmeal moth (Plodia interpunctella), which results in laying eggs or simply paralyzing the larvae. We studied the influence of the parasitoid’s attack on the larval development of indianmeal moth. The third larval instars of the same age were collected from the experimental colonies and each larva introduced in an acrylic cube (2 x 2 x 2 cm) treated with: 1) empty, 2) three rice grains, 3) three rice grains and a female parasitoid without ovipositor (by removing) and 4) three rice grains and a paralyzed larva. The larval activity in the experimental cube was photographed every five minutes until the larva died or pupated. Only the larvae in the cube with paralyzed larvae could pupate and emerge. The other larvae in the three treatments died before pupating, although the survival time was significantly different in relation to the treatment (F=5.27; df=2,14; P=0.019); the larvae in the empty cube had a shorter survival time than those in the rest of treatments. The results indicated that the paralyzed larvae could be fed by the health larvae and contribute to prevent population crush in the situation of food shortage with the presence of the parasitoids. The host parasitoid interaction between indianmeal moth and Bracon hebetor might not always be negative to the indianmeal moth population.

Scirtothrips dorsalis Hood is a newly advent pest on citrus in Jeju. Both larvae and adult attack the new shoots and young and matured fruits of citrus. S. dorsalis is highly polyphagous with over 100 recorded species, but not known in Jeju. As a result from investigating the host plants in and/or around citrus orchards in Jeju during 2009 to 2010, they were 25 families 39 species. The total thrips examined on those plants were 13 species, and the richness thrips among them was S. dorsalis, Frankliniella occidentalis, Thrips tabaci and Thrips hawaiiensis. The widespread host plants of S. dorsalis were Mallotus japonicus, Paederia scandens, Hedera rhombea, Cayratia japonica and Clematis apiifolia and they can be also used for monitoring plants. On early May, the larvae of S. dorsalis were first investigated on the shoots of Mallotus japonicus, Lonicera japonica, Paederia scandens, Viburnum awabukira, Fraxinus rhynchophylla and Celtis sinensis. The other thrips species except S. dorsalis and T. tabaci, especially F. intonsa, T. hawaiiensis, T. flavus and T. coloratus were just found on flower stalks during the blooming season.

Developmental time, mummification, pupal mortality, sex ratio of a South Korean strain of Aphelinus varipes Förster parasitizing the green peach aphid, Myzus persicae were studied at 20, 25 and 30℃ in controlled climate cabinets. Plastic container with sweet pepper(Capsicum annuum L.) were used as experimental units. Green peach aphid in different larval instars and as adults, reared at the three different temperatures, were presented to A. varipes in a 'no-choice' and 'choice' situation for 6h. These presentations were done at 25℃ in each experiment to avoid an influence of temperature on parasitization rate. In case of no-choice test, more 1st(24%), 2nd(22%) and 3rd(38%) instar aphids were parasitized than 4th(14%) instar and adult(10%) among the aphids reared at 25℃. In case of choice test, more 1st(41%), 2nd(42%) and 3rd(29%) instar aphids were parasitized than 4th(13%) instar and adult(0%) among the aphids reared at 25℃. Pupal mortality of the parasitoid was not influenced by temperatures. The sex ratio of A. varipes was male-biased, and varied between 49.4% females developed from aphids reared at 30℃ and 42.8% from aphids reared at 20℃. The sex ratio was not significantly influenced by host stages. The developmental time of A. varipes parasitizing the green peach aphid ranged from 26.1days at 20℃ to 11.1days at 30℃.

The beetle family Ciidae, represented by Octotemnus laminifrons Motschulsky, 1860 and Octotemnus japonicus Miyatake, 1954 is presented for the first time in Korea. The beetle family Ciidae Leach is a relatively moderate family, which comprises about 640 described species in 42 genera worldwide. This family is distributed throughout the world. Ciids are minute fungus-feeding beetles, which are associated with the mycelia and fruiting bodies of wood-rotting fungi. These beetles are considered mycetobiont because they depend upon the basidiocarps for food and breeding throughout their life span. And also ciids are important components of the saproxylic fauna of many forests ecosystems and a number of species are considered rare or threatened and are associated with old growth forests or undisturbed forest conditions. A habitus photographs of adults, description, illustrations of diagnostic characters, and host fungi are provided.

A polydnavirus, Cotesia plutella bracovirus (CpBV), encodes host translation inhibitory factors (HTIFs). Two HTIFs have been identified and named as CpBV15α and CpBV15β. HTIFs specifically inhibit host gene expression at post transcriptional level. This suggests that HTIFs can discriminate host mRNAs for their inhibition. To test this hypothesis, we chose a storage protein 1 (SP1) for a target and CpBV15β for non-target genes. Both target and non-target genes were constructed in a cloning vector by cloning their 5'UTR+ORF and in vitro transcribed. The capped partial mRNAs were in vitro translated using rabbit reticulocyte lysate in the presence or absence of HTIFs. Translation of SP1 mRNA was significantly inhibited by the HTIF, but those of CpBV15α and CpBV15β were not. We prepared chimeric mRNAs by exchanging 5'UTR and ORF of both target and non-target genes. Inhibitory activity of HTIFs was dependent on the 5'UTR structure. Target 5'UTR had more complicated secondary structure than non-target 5'UTR in terms of free energy required for unwinding. To identify the target molecule of HTIF to discriminate 5'UTR, an immunoprecipitation using HTIF antiserum was conducted. HTIF was co-precipitated with eIF4A that would be required for unwinding the secondary structure of mRNA. These results suggest that HTIF of CpBV can sequester host eIF4A, any mRNAs possessing complicated secondary structures in their 5'UTRs would be difficult to recruit initiation complex for efficient translation.

Effects of host density and refuge on the sex ratio of progeny of hymenopterous parasitoids was tested with Bracon hebetor Say parasitizing Plodia interpunctella (Hübner). The overall sex ratio (male/total) of progeny produced per female with and without refuge was estimated to be 0.49 and 0.41, respectively. Regardless of refuge, the sex ratio decreased as host density increased. But, at host density of 128 with refuge the sex ratio was significantly lower than that without regfuge (t=-2.17, df=24; P=0.040). The number of pupae per host larva with refuge was similar to that without refuge at the host densities tested (t=-0.10, df=53.4; P=0.921). The number of attacked host larvae showed significantly different at all host densities with and without refuge (t=-3.33, df=209; P=0.001).