• Journal of the Korean Chemical Society
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• v.63 no.6
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• pp.415-419
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• 2019

Fipronil is an insecticide that belongs to the N-phenylpytazole and has been used mainly for an insect pest control. However, it is known that acute poisoning of the human body causes various symptoms such as dizziness, muscle weakness, dyspnea, skin irritation, and increased heart rate. Lately, eggs containing fipronil have been distributed and toxic problems are spreading around the world. In this study, we tried to develop analytical methods to evaluate the exposure of fipronil and fipronil sulfone in animal serum samples. The differences according to mobile phase and the results of liquid - liquid extraction and solid phase extraction pretreatment method were compared. Distilled water (A) and acetonitrile (B) were selected for the mobile phase, and the pretreatment method was determined by solid phase extraction. As a result of the method validation, the intra-day / inter-day accuracies were 82.2~114.1% and the precisions were less than 20%. The detection limit was 0.027 ng/ml for fipronil and 0.087 ng/ml for fipronil sulfone. The linearity obtained was satisfying, with a coefficient of determination (r²) higher than 0.99. The concentrations in some animal sera were determined using the methods of analysis for fipronil and fipronil sulfone in animal sera developed in this study. Using the method developed in this study, it could be used as an analytical method for human bio-monitoring of fipronil and fipronil sulfone as well as animal serum.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.269-277
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• 2003

Some species of true bugs have become serious problems in rice, upland crops, and tree fruits. It would be meaningful to understand research status by reviewing articles on those true bugs in Korea. Articles on those bugs published in several scientific Korean journals were reviewed, except articles on true bugs on rice plants; CD Part 1 included classification and morphological studies on eggs and larvae of Piesma spp., on external genitalia of Gonopsis affinis, and on spermathecae of some Podopinae and Asopinae species. $\circled2$ Development and growth analysis of Piesma sp., P. maculata, and 2 species of Coreidae were reviewed in part 2. $\circled3$ In part 3 we reviewed with major pest bug species on soybean, sweet persimmon, yuzu, citrus, chrysanthemum, and Cynanchum wilfordii, and insect fauna in mountain areas. $\circled4$ In part 4, damage levels in soybean, sweet persimmon, yuzu, grapes were reviewed. $\circled5$ ID In part 5 we reviewed seasonal occurrence patterns of Halyomorpha halys, Plautia stali, Riptortus clavatus in sweet persimmon orchards, of some species in soybean fields, of Nysius plebejus on chrysanthemum, and of Tropidothorax cruciger on Cynanchum wilfordii. $\circled6$ Chemical control methods in a sweet persimmon orchard, in grapevine yards, in a soybean field, and in a chrythansemum field were introduced in part 6. Some laboratory bioassay on insecticides against R. clavatus were mentioned, too. $\circled7$ Finally in part 7, researches on transmission by Halyomorpha halys and Cyrtopeltis tenuis of micoplasma-like organism which is a pathogen of paulownia withces' -broom to Catharanthus roseus were reviewed.

• Korean Journal of Organic Agriculture
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• v.25 no.3
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• pp.631-642
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• 2017

For effective control of insect pest which can outbreak in a field during crop cultivation, various control agents such as eco-friendly agricultural materials (EFAM) including microbial control agents and chemical pesticides have been applied at fields and these control agents may be treated simultaneous or sequential in the same field to suppress diverse pests and diseases. The agents may influence each other and control efficacy may also differ from interactions. Therefore we need to test compatibility of microbial control agents with other agricultural agents. In this study, we investigated influence of pre-treated EFAMs, which are registered for whitefly control in greenhouse, on germination, mycelial growth and control efficacy of Isaria javanica isolate against sweet potato whitefly. The results showed that a mixture of paraffin oil+cinnamon oil among 4 EFAMs highly reduced germination ($8.9{\pm}1.3%{\sim}24.5{\pm}0.9%$) and mycelial growth ($0.81{\pm}0.01cm{\sim}0cm$) of I. javanica. To investigate the effects of the treatment interval between EFAMs and I. javanica on sweet potato whitefly control, four different EFAMs were pre-treated 0, 1, 4, and 7 days before applying I. javanica. Pre-treatment of four EFAMs inhibited insecticidal activity of I. javanica against sweet potato whitefly. Therefore when EFAMs and a mycopesticide using I. javanica spray simultaneous or sequential, application of EFAMs need more than 7 days interval after treatment of mycopesticide at field.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.31-40
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• 2001

Host plants or Ectinohoplia rufipes (Motschulsky) (En) were investigated in golf courses and laboratory. E. rufipes adults fed on 61 plant species of 27 families out of 101 plant species of 41 families supplied in laboratory. In addition, twenty-seven plant species in 8 families were observed to be fed on from golf courses. Thus, total number of host plants of E. rufipes were 84 species in 29 families. E. rufipes adults preferred Japanese green alder (Alnus firma) , cherry apple (Malus sieholdii), cherry (Prunus serrulata var. spontanea) and sweet oliver (Osmantus asiaticus) in golf courses . The preference of E. rufipes adults with A. firma , P. serrulata vu. spontanea and O. asiaticus was bioassayed in laboratory. E. rufies adults preferred A. firma consuming 58.1% to O. asiaticus and p. serrulata vats. spontanea. The most number of E. rufipes adults was attracted to damaged leaf of A. firma by E. rufipes representing 45.3clo and followed by artificial damaged leaf representing 26.5% , untried feeding leaf representing 12.9% and undamaged leaf representing 4.0%. More E. rufipes adults were attracted to damaged leaf of A. firma by 67.5% than artificially damaged leaf by 30.5% or undamaged leaf treated with feces of E. rufipes by 2%.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.42-47
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• 2016

To examine the natural regeneration in the natural mixed-broadleaved forest, flowering, fruiting, seed-fall, and seed viabilities of Acer pseudosieboldianum (Ap) were investigated in Mt. Jungwang, Gangwon-do, from 2009 to 2015. The flower of Ap consisted many male and bisexual flowers on the corymb. Flowering dates are differed between sex morph in the same inflorescence. Stamens are stop growing and disappeared after pollinated pistil begin to grow in bisexual flowers, and male flowers have vestial pistil. The flowers of Ap might be pollinated by Apis mellifera, Andrenidae spp. and Syrphinae spp. Ap had some mechanism to prevent from self pollination with heterodichogamy. Mean annual seedfall of Ap was 70,780 ea/ha (ranged 310~234,840 ea/ha). Annual seedfall of Ap varied severely, and the maximum was about 760 times the minimum. Annual seed production of Ap might be to a normal distribution. Rates of damaged or decayed seeds are highest 59.3%, and those of sound seeds are 23.9%, Those of undeveloped and empty seeds are 9.2% and 7.6%, respectively. The most important factors influencing sound seed production might be the density and activities of insect pollinators and sucking pest in the flowerwing period, middle-late May. Successful regeneration of Ap might be in masting year and on the gap sites with proper conditions to germinate and grow. To understand the natural regeneration of deciduous hardwoods, further study on the characteristics of flowering and fruiting, pre- and post-dispersal seed predation, and annual variation on these factor should be needed.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.849-857
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• 2016

In the growth of the Rubus coreanus Miquel fruits, the unripened (10 days) and ripened (25 days) fruits after flowering were harvested. The chemical characteristics of different maturational stages of the unripened and ripened fruits were investigated. Total amount of phenolic compounds was 4.00-7.56% in the unripened fruits and 3.78-5.57% in the ripened fruits, respectively. Furthermore, total amounts of organic acids such as malic, citric, succinic, and oxalic acids were 16.40 mg/100 g in the unripened fruits and 28.82 mg/100 g in the ripened fruits, respectively. In organic acids of the unripened and the ripened fruits, citric acid (8.76-15.47 mg/100 g) was the highest amount among other organic acids. Soluble sugars were significantly increased from 11.07 to 21.54% in the unripened and ripened fruits. Therefore, ripened fruits had the high levels of phenolic compounds, organic acids and soluble sugars. For the biological studies of R. coreanus, methanol extracts of R. coreanus leaves, fruits, and stems were evaluated for their insecticidal activities against Myzus persicae (Hemiptera: Aphididae), Plutella xylostella (Lepioptera: Plutellidae) and Spodoptera litura (Lepioptera: Noctuidae) by leaf dipping method. From these results, the extract of R. coreanus leaves revealed potent insecticidal activity against P. xylostella. However, the methanol extracts of R. coreanus fruits and stems had no any insecticidal activity against M. persicae, P. xylostella and S. litura. The R. coreanus leaves have promising potential as new insecticidal agent against P. xylostella.

• Korean journal of applied entomology
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• v.50 no.1
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• pp.39-46
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• 2011

This study analyzed effects of different sound treatments in frequencies and intensities on digestion and immune physiological processes of the beet armyworm, Spodoptera exigua larvae. Without effect on egg hatch, sound treatments with 100-5,000 Hz at 95 dB suppressed feeding behavior and inhibited a digestive enzyme activity. In addition, two dimensional electrophoresis of midgut luminal proteins indicated a marked difference of the sound-treated larvae. In response to 5,000 Hz at 95 dB, larvae showed a significant decrease in hemocyte nodule formation against fungal challenge along with significant suppression in phospholipase $A_2$ activity in hemocyte and plasma. With increase of sound frequencies, the treated larvae showed an enhanced susceptibility to insecticides. Such sound frequency effect was significantly modulated with different sound intensities. These results suggest that sound treatment may give adverse stress to physiological processes of S. exigua larvae and may be applied to a nonchemical insect pest control.

• Korean journal of applied entomology
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• v.50 no.1
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• pp.55-63
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• 2011

This study was conducted to develop an artificial diet for the mugwort looper, Ascotis selenaria (Lepidoptera: Geometridae), which is an insect pest to leaves of citrus (Citrus unshiu). Corn and soybean powder were selected as main nutrient sources for larvae of A. selenaria after several diets consisted of wheat germ, corn, kidney bean and/or soybean were tested for larval development and survival. A higher amount of the main nutrients in the diet increased the larval survivorship. Addition of yeast and cholesterol in diet increased the larval survivorship. Finally the composition of diet was decided as followings; corn 100 g, soybean 100 g agar 25 g, Brewers' yeast 30 g, cholesterol 0.5 g, Vanderzant vitamin mixture 2 g, Wesson's salt mixture 2 g, sorbic acid 2 g, ascorbic acid 2 g, and methyl-4-hydroxybenzoate 2.5 g, and distilled water 1 liter. Development periods of larvae and pupae, survival rate and fecundity of A. selenaria reared on the diet were not significantly different with those on the host plant, citrus leaves. Larvae of early instars were reared in a group, while larvae of later instars (5-6th) were reared individually. Adult mating was conducted in a plastic cage and an oilpaper covered with a gauze was provided as an oviposition site.

• Asian Journal of Turfgrass Science
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• v.15 no.3
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• pp.119-126
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• 2001

The susceptibility of Ectinohoplia rufipes, insect pest of landscaping trees in golf courses to registered insecticides in golf courses was investigated. In addition, effect of host plants, Ainus firma, Prunus serrulata var. spontanae, and Osmantus asiaticus on susceptibility of E. rufipes were tested in laboratory with efficacy of some insecticides in laboratory and fields. The insecticides used in experiments were cabaryl 40%+phosalone 20% WP, chlorpyrifos-methyl 25% EC, chlorpyrifos 20% + diflubenzuron 7% n, deltamethrin 1% EC, ethopenprox 8% +diazinon 25% WP, and fenitrothion 50% EC. Mortalities of E.rufipes were 100% except chlorpyrifos-methyl. when A. firma leaves dipped in recommended concentration of given insecticides were supplied as food to adult of E. rufipes. LC$_{50}$s of insecticides were different depending on host plants, that is, those of deltamethrin were 0.21 ppm in Ο. asiaticus, 0.45 ppm in P. serrulata var. spontanae, and 0.77 ppm in A. firma. LC$_{50}$s of fenitrothion were 24.1 ppm, 64.0 ppm, and 11.0 ppm and those of chlorpyrifos-methyl were 97.2 ppm, 40.6 ppm, and 29.6 ppm, respectively. LC$_{50}$ was the lowest in Ο. asiaticus and that of chlorpyrifos-methyl and fenitrothion was the lowest in A. firma. Deltamethrin was the most effective against adult of E. rufipes in field like in laboratory and persisted in two weeks.weeks.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.22-29
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• 2011

Host plants of Popillia flavosellata (Coleoptera: Ruteridae) were investigated at the courses of three golf clubs, East Valley Golf Club, Anyang Benest Golf Club, and Anseong Benest Golf Club and their surrounded forests. In addition, seasonal occurrence was examined from East Valley Golf Club using Japanese beetle pheromone lure and a eugenol feeding attractant. Twenty six species of 25 genera in 18 families were recorded as hosts of P. flavosellata from given surveyed golf clubs. Out of them, 22 species of 21 genera in 15 families were newly recorded host plants of P. flavosellata. Thus, host plants of P. flavosellata were 49 species of 41 genera in 23 families in total including hosts from literatures. The main damage part of P. flavosellata adult was flower of host plants. Peak activity of P. flavosellata adult was observed around 20 June. Mean numbers of attracted P. flavosellata adults at the peak day were 197.6/trap/day in 2008 and 268.1 in 2010, respectively. Occurrence of P quadriguttata was much lower compared with P. flavosellata at the given golf club. That is, mean numbers of attracted P quadriguttata adults from the same trap at the peak: day were 0.4/trap/day in 2008 and 2010, respectively.