• Journal of Korean Society of Forest Science
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• v.100 no.2
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• pp.131-135
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• 2011

To examine the sex morph, fruiting characteristics and seed viabilities of Acer palmatum var. matsumurae (Koidz.) Makino, the flowers and seed-sets of 101 trees were collected from early April to late October 2010, and floral structure and seed viability were studied. Among investigated 101 trees, 73.3% of trees were protandrous (PA: pollen is shed before stigmas are receptive) and 26.7% were protogynous (PG: stigmas are receptive before pollen is shed). Acer palmatum var. matsumurae has heterodichogamous sexual system. Number of flowers and seed-sets per inflorescence are significantly different between sex morphs, and PA has more flowers and seed-sets per inflorescence than PG. Rates of sound seeds and decayed seeds are significantly different between sex morphs. Rates of sound seeds were 46.4% in PA, but 65.6% in PG. and rates of decayed seeds were 49.6% in PA, but 23.6% in PG. The differences of decayed seeds' rates between sex morphs might be related with the timing of pistil flower blooming and insect pests' outbreak.

• Korean journal of applied entomology
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• v.61 no.3
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• pp.507-512
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• 2022

The Gypsy moth, Lymantria dispar (Linnaeus, 1758) (Lepidoptera: Erebidae) is a serious pest that attacks forest as well as fruit trees. We sequenced the 15,548 bp long complete mitochondrial genome (mitogenome) of this species. It consists of a typical set of genes (13 protein-coding genes, 2 rRNA genes, and 22 tRNA genes) and one major non-coding A + T-rich region. The orientation and gene order of the L. dispar mitogenome are identical to that of the ancestral type found in majority of the insects. Phylogenetic analyses using concatenated sequences of 13 PCGs and 2 rRNAs (13,568 bp including gaps) revealed that the L. dispar examined in our study, together with other geographical samples of L. dispar in a group forming the family Erebidae and consistently supported the monophyly of each family (Erebidae, Euteliidae, Noctuidae, Nolidae and Notodontidae), generally with the highest nodal supports.

• Korean journal of applied entomology
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• v.47 no.1
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• pp.107-110
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• 2008

Tropical fire ant, Solenopsis geminata (Fabricius) is distributed over the tropical and temperate areas. It is a polyphagous pest attacking to various plant and causes the pain to the people doing outdoor work. So it is known for a hygienic pest to human being, especially the people doing outdoor activities. It can cause severe pain to human, even with just a bite. Of particular concern is the possibility of its settlement in this country, if it invade to the farmlands and/or forests of Jeju Island and southern part in Korea. It is listed as a regulated pest in Plant Quarantine Act of Korea. This ant is usually imported through a ship and early settled in the port area where it is already distributed. Recently its distribution is rapidly spreading into Southeast Asia and southern part of China. In Korea, it was detected the one time in 1990s, but was detected the ten times from 2000 to 2006 by an imported plant quarantine process. Therefore, we would like to provide some information on the species, including morphology, distribution, host plant, damaged symptom and its general bionomics, which will be useful data for plant quarantine process and control.

• The Korean Journal of Pesticide Science
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• v.16 no.4
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• pp.322-327
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• 2012

Fate of fenitrothion aerially sprayed to control pine wood nematode (Bursaphelenchus xylophilus) was studied in a forest of Haman area. And the monitoring of fenitrothion was conducted in a stream flowed from forest area of Gijang sprayed fenitrothion. Fenitrothion 50% EC was diluted 100 times and applied two or three times using helicopter in Haman and Gijang, respectively. Average fenitrothion deposits on forest floor ranged from 6% of standard aerial application rate. Following to the second application, fenitrothion deposits in the pine needle ranged from 0.6 to 0.9 mg/kg and then rapidly decreased to 0.01 mg/kg after 109 days. Deposits on the plant washed off by rainfall and reached to soil surface was 1.3% of the application rate. All of fenitrothion on the ground resided in the forest floor covering the soil surface, where fenitrothion residues were decreased to a tenth at 109 days after the second application, but they were not detected in sol beneath it. And the only low level of fenitrothion residues, 0.0009 mg/L, was detected in runnel of the experimental forest just after aerial application. The concentration of fenitrothion in effluent from Gijang area was less than detection limit (0.0001 mg/L) during the entire period.

• Korean journal of applied entomology
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• v.18 no.4 s.41
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• pp.161-167
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• 1979

The study has been carried to investigate a possibility to control several major insect pest of forest by microbial pathogens existing in nature as one of the biological control measure. Microorganisms including polyhedral virus isolated from diseased fall webworm were total of 4 kinds pathogenic microbes among these 4 kinds were polyhedral virus and Bacillus .species. Control effect of these two pathogens appeared to be $70.6\%$ and $49.5\%$, respectively, when they were compared with those of control plot that was $27.8\%$. Each one of bacterium species and fungus species were isolated from diseased Japanese alder leaf beetle. Pathogenisity to the healthy beetle was recognized by the fungus species, while the bacterium showed none of pathogenisity. The fungus was identified as Beauveria sp. and its effect on the beetle control was $96.2\%$ while untreated plot showed $49.2\%$ of dead beetles in the same period. Fifteen species of microbes were isolated from diseased larvae of pine gall midge. Six species out of 15 showed certain level of insecticidal effect to the larvae of the insects. The highest efficiency was showed by a fungus species, Fusarium sp. and was followed by Bacillus SP. I, Spicaria sp. pathogens isolated from larvae of pine gall midge did not affected to both of Japanese alder leaf beetles and fall webworms in any means.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.363-367
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• 2008

Abamectin 1.8% EC and emamectin benzoate 2.15% were evaluated the simultaneous control effect of both insect pests on black pine (Pinus thunbergii) against Thecodiplosis japonensis and Matsucoccus thunbergianae. Abamectin 1.8% EC was highly effective against T. japonensis and M thunbergianae, however, emamectin benzoate was highly effective against only M. thunbergianae when abamectin and emamectin benzoate were applied through trunk injection against T. japonensis and M thunbergianae at the rate of 1 ml per cm in diameter of breast height. The rate of gall formation of T. japonensis was 0% at the applied year, but 85% at the following year. However, the rate of gall formation was over 90% at the treatment of emamectin benzoate showing no difference compared with control. Abamectin 1.8% EC and emamectin benzoate 2.15% showed high control efficacy representing 89.1% and 91.4% against M. thunbergiana, respectively.

• Journal of Korean Society of Forest Science
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• v.89 no.5
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• pp.685-690
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• 2000

Caliroa carinata (Zombori) has heavily damaged the forests of Quercus mongolica in Sangju, Kyongbuk, Korea since 1996. However, information on the ecology and control of this pest was badly scarce. Thus we tried to study the ecology and chemical control of the sawfly through this study. Caliroa carinata is one generation per year. The adult sawflies emerged from June 8 to July 5 with peak at June 18. A female adult laid 11 eggs in rows on the backside of a leaf along the midribs and larger veins. Larvae have six instars, and the developmental period required to complete the larval stage was 19 days and 17 days at temperatures of $20^{\circ}C$ and $25^{\circ}C$, respectively. Each larval stage required 2-4 days to complete the development. The sawfly mostly preferred Quercus mongolica and Q. dentata, while avoiding Q. variabilis. Such insecticides as Tebufenozide, Flufenoxuron, Etofenprox, and Fenitrothion were sprayed on host plant leaves infected with test larvae in order to study the mortality. After 3 days of insecticide treatments, the mortalities were thoroughly examined. All insecticides showed higher than 95% of mortalities. Control values were also higher than 93%. The optimal season of insecticide application for pest control was estimated from late June to early July.

• Journal of Korean Society of Forest Science
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• v.89 no.5
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• pp.630-633
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• 2000

The damage by the black-tipped sawfly, Acantholyda posticalis posticalis, has been increasing all over the area of Korean pine(Pinus koraiensis)stands in Korean peninsula. This study was conducted to provide basic information for the management and control of this pest by investigating the feeding quantity of pine needles during the larval stage. The results were summarized as follows : The total needles damaged in the larval stage of the black-tipped sawfly were 9,584mm in length on an average and those of female and male were 11,774mm and 7,394mm, respectively. The total length ingested actually was 7,797mm and it was equivalent to 81.4% of the total length damaged. Early larval stage showed a little feeding and it was equivalent to 17% of total quantity. On the contrary, the feeding quantity in late larval stages of fourth and fifth instars amounted to 83%. The number of the frass excreted per larva was about 1,160, and the difference between male and female was not showed, whereas it showed remarkable difference among larval instars.

• Journal of Korean Society of Forest Science
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• v.83 no.4
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• pp.498-504
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• 1994

The damage by the black-tipped sawfly, Acantholyda posticalis posticalis Matsumura, has been incheasing at several locations in central part of the Korean peninsula. This study was undertaken at selected plots in locality of Kapyung-gun. Kyunggi Province from 1984 through 1987. The purpose of this study was to provide basic information for integrated control of this pest and to determine the economic threshold by investigating the pest-host interactions with special reference to damage analysis. The results obtained were as follows ; 1. One year old cone formation began to be reduced when 30-40% of the needles were destroyed. With 70% of defoliation, few cones were produced. 2. Number of two year old cone formation and amount of cones began to be reduced when 61-70% of the needles were destroyed ; economic threshold of the defoliation rate retarding the seed production was 51%. 3. Growth of the trees was significantly reduced when more than 50% of the needles were destroyed, and cone production began to be retarded at 30-40% of defoliation. Therefore, it was determined that the economic thresholds requiring the control practices to keep normal tree growth and cone production from being reduced were 50% and 30%, respectively.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.333-339
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• 2020

Pheromone-based techniques are becoming a viable strategy of insect pest management as facilitated by the exponential increase in numbers of pheromone identifications from many insect pests. This is the report on the efficacy of pheromone-mediated chemical communication disruption (PCD) technique against the Korean population of smaller clearwing moths, Synanthedon tenuis (Butler) (Lepidoptera: Sesiidae) using its female sex pheromone component, (Z, Z)-3, 13-octadecadien-1-ol. The PCD trials were carried out four times during 2016 and 2017 in persimmon orchards located at Suncheon and Jinju Cities in Korea, and the PCD efficacy was expressed as the mean differences in the seasonal catches of S. tenuis males in the PCD and control plots. The seasonal male moth catches in monitoring traps installed in the PCD plots were significantly lower as compared with those installed in the control plots. Consequently, the PCD efficacy in the experimental orchards ranged from 95.2-100% with an average efficacy of 98.8 ± 1.2%, revealing a future possibility of pheromone-based management of S. tenuis.