• Journal of Microbiology and Biotechnology
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• v.4 no.4
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• pp.322-326
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• 1994

Bacillus thuringiensis strain BT-14 was isolated from alfalfa dust in Korea. The strain BT-14 produced one bipyramidal crystal and one spore in the cell. The biochemical characteristics of the strain BT-14 were similar to those of Bacillus thuringiensis subsp. kurstaki HD-l. Examination of its antibiotic resistance revealed that while the strain BT-14 was less resistant than BTK HD-l to ampicillin, gentamycin, neomycin and tobramycin, it was more resistant to amikacin than BTK HD-l. The $\delta$-endotoxin crystal of strain BT-14 consisted of a single protein with a high molecular weight of ca 135 KD on a 10% SDS-PACE. The strain BT-14 contained at least nine different plasmids with sizes of 2.9, 5.3, 5.8, 6.2, 9.4, 15.1, 18.1, 23.1 and 79 Kb. In insect bioassay, the isolated strain BT-14 showed lethality of 67% against Plutella xylostella larvae at dilution of 5$\times$$l0^{-4}$ (5$\times$l0 to 3$\times$$l0^2$ spores/ml), which is, almost equivalent to that of BTK HD-l.

• Ocean and Polar Research
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• v.42 no.1
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• pp.1-13
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• 2020

We analyzed the characteristics of meiofaunal communities in the northern part of Jeju Island and the environmental factors affecting the meiofaunal communities. For the analysis of the communities, subtidal sediments containing meiofauna were collected from 6 sites (3 shallow sites and 3 deeper sites) on the northern coast of Jeju Island in April, June, August, and October 2017. The sediment samples were collected by SCUBA using a syringe. After isolating and counting meiofauna from the sediment using a series of sieves and centrifugation, the density of the meiofauna was expressed as individuals/10 ㎠. Density of meiofauna was lower in August compared to April and June, and the density determined in October was higher than August. During April and June, the meiofaunal communities at the shallow sites (i.e., ST 1, 2, and 3) were significantly different from the meiofaunal communities at deeper sites (ST 4, 5, and 6, p < 0.01). However, such spatial variation in the meiofaunal communities was not obvious in August and October. The most dominant meiofaunal taxa were harpacticoids, followed by nematodes and nauplius larvae. These three taxa accounted for 90% of the total meiofauna density. Abundance of harpacticoids and nematodes showed a significantly negative correlation with the water depth. BIO-ENV analysis indicated that the total organic nitrogen (TON) and the water temperature exerted a significant influence over the meiofaunal communities at the sampling sites.

• Korean journal of applied entomology
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• v.58 no.3
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• pp.225-228
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• 2019

The genus Chrysaster Kumata is one of the members in Lithocolletinae of Gracillariidae (Lepidoptera: Gracillarioidea). Chrysaster hagicola Kumata, 1961 has been the only known species of the genus in Korea so far. In this study, we report another species, Chrysaster ostensackenella (Fitch, 1859) for the first time from Korea. The samples of C. ostensackenella were collected as larvae and adults on Robinia pseudoacacia L. (Fabales: Fabaceae). Diagnostic characteristics with a brief description are given, as well as, photographs of adults and genitalia of both sexes are provided. A further study on C. ostensackenella is strongly recommended, especially for the business of honey, as this species is recently known to be a serious pest on acacias (black locust) in China.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.772-776
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• 2004

Physiological and molecular characteristics of Bacillus thuringiensis SR6 and SR8 were investigated, and phase contrast and electron microscopies revealed that a large rhomboidal crystal protein was present in the sporulating cells. SDS-PAGE and Western blot analyses showed that B. thuringiensis SR8 produced 70 kDa protein much more than other proteins, and that the 70 kDa protein could bind to the antibody of B. thuringiensis subsp. tenebrionis-crystal toxin protein, indicating that the crystal 70 kDa protein has an immunological homology with B. thuringiensis subsp. tenebrionis-crystal toxin protein. The DNA fragment of B. thuringiensis subsp. tenebrionis-toxin gene was detected in B. thuringiensis SR6 and SR8 by using PCR amplification analysis. Furthermore, the insect bioassay showed the insecticidal activity against Colorado potato beetle larvae. Based on the physiological and molecular similarities to B. thuringiensis subsp. tenebrionis, it is suggested that the B. thuringiensis SR6 and SR8 may be mutants of the B. thuringiensis subsp. tenebrionis strain overexpressing the crystal of 70 kDa toxin protein.

• Korean journal of applied entomology
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• v.61 no.3
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• pp.513-517
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• 2022

An investigation of the severe destruction of wood ear mushroom (Auricularia auricula-judae), which were commercially cultivated in a plastic house in Hwabuk-myeon, Jeju-si, South Korea from April to August 2021, revealed a tenebrionid beetle subsequently identified as Platydema takeii Nakane, 1956 (Coleoptera: Tenebrionidae: Diaperinae). To the best of our knowledge, this is the first report of a tenebrionid species infesting commercially cultivated mushrooms in South Korea. The damage symptoms and diagnosable characteristics of adults and larvae of P. takeii are provided in this study.

• Korean journal of applied entomology
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• v.54 no.2
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• pp.111-114
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• 2015

We report three lepidopteran insect pests of non-astringent persimmon leaf for the first time from Korea; Hypocala deflorata (Noctuidae), Teliphasa elegans (Pyralidae), and Cuphodes diospyrosella (Gracillariidae). Larvae of these species were collected from an organic farming or abandoned persimmon orchard in Changwon and Jinju cities, Gyeongnam province, and reared for the identification in the laboratory. Some information, such as collection records, hosts, simple morphological characteristics, and ecology were introduced for each species.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.357-360
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• 2020

We identified Jolcham oak (Quercus serrata Thunb. ex Murray) (Fagales: Fagaceae) as a new host tree for Callipogon relictus Semenov (Coleoptera: Cerambycidae), a Korean natural monument and an endangered species, in Gwangneung Forest, South Korea. We herein report the morphometric characteristics of C. relictus larvae found in a Q. serrata tree and provide a revised list of C. relictus hosts.

• Korean journal of applied entomology
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• v.50 no.3
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• pp.253-256
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• 2011

The walnut leaf beetle, Gastrolina depressa, belongs to family Chrysomelidae (Coleoptera), and is one of the major pests of walnut trees. G. depressa eggs were oval and dark orange. The three G. depressa larval instars were gray in color. The larval period was approx. 8.14 days ($24^{\circ}C$, 16L:8D). Adults of both sexes were dark blue, and females were larger than males. Overwintered adults emerged in late April, and laid eggs in clusters on young leaves of the host tree. Mature 3rd instar larvae pupated after a short prepupal period. Adults emerged starting mid-May and entered into diapause shortly afterward.

• Animal Systematics, Evolution and Diversity
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• v.12 no.2
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• pp.91-99
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• 1996

The complete larval development of Philyra pisum De Hann, 1841 from hatching to the megalopal stage was obtained by culture in the laboratory. Two zoeal and one megalopal stages are described and illustrated . The frist zoea of the present species is very similar to those of other two Philyra species except for the reduced carapace spines. The first zoeae belonging to the subfamily Philyrinae can be divided into two groups based on the zoeal characteristics: the first group is composed of Arcania septemspinosa, A. undecimspinosa elongata, and Myra fugax, whereas the second group is composed of Philyra corallicola, P. syndactyla, and P. pisum.

• International Journal of Industrial Entomology and Biomaterials
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• v.17 no.1
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• pp.125-129
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• 2008

The purpose of this study was to investigate the characteristics of Mamestra brassicae nucleopolyhedrovirus (MabrNPV)-K1 isolated in Korea. Polyhedra of MabrNPV-K1 showed irregular appearance in shape with the average diameter $1.8{\mu}m$. MabrNPV-K1 contained a number of nucleocapsids within a viral envelope embedded in polyhedron. The polyhedrin of MabrNPV-K1 was composed of single polypeptide with a M.W. of approximate 31 kDa which is identical to the commercialized MabrNPV, Mamestrin, as a biological control agent. The nucleotide and amino acid sequences within the coding region of MabrNPV-K1 polyhedrin shared 99.0% similarity with the polyhedrin gene from previous reported MabrNPVs. The median lethal concentrations ($LC_{50}$) of MabrNPV-K1 and Mamestrin to M. brassicae larvae were $3.9{\times}10^3$ PIBs/larva and $6.0{\times}10^4$ PIBs/larva, respectively. Mortality of the MabrNPV-K1 against to the third instars larvae was 15 times higher than that of the Mamestrin. The median lethal times ($LT_{50})$ of MabrNPV-K1 by the concentration of polyhedra were lower ($4.4{\sim}6.1$ days) than those of Mamestrin ($4.1{\sim}8.6$ days). These results suggest that a local strain MabrNPV-K1 has high pathogenicity to M. brassicae and may be useful for the development of biological control agent to control this.