• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.3
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• pp.151-161
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• 2016

This study was conducted to find out influence of dormancy level and carbon concentration on freezing hardiness in bourse shoot of 'Fuji' apple tree. Bourse shoot of 'Fuji' adult apple tree grafted on M.26 and M.9 rootstocks were used as experimental materials. Dormancy levels of bourse shoot were categorized according to the periods as follows the internal dormancy (late January), the early days after internal dormancy breaking (early February), the late days after internal dormancy breaking (late February), the bud break (late March), and the full bloom (late April). Chilling temperatures with bourse shoot were ranged from 0 to $-40^{\circ}C$. Also, the freezing hardiness according to carbon concentrations were investigated on 'Fuji'/M.9 apple tree that defoliated severely by Marssonina blotch (defoliation) and that of below the average 20 cm in shoot length through heavy crop load (weakness). Results showed that freezing hardiness of bourse shoot may become weaker after internal dormancy breaking. There was no differences in the carbon concentration of bourse shoot of 'Fuji' apple tree grafted on M.9 and M.26, so may be resulted in no difference in freezing hardiness both of bourse shoot grafted on M.9 and M.26 rootstock. Carbon concentration in bourse shoots with weakness and C/N ratio in bourse shoots with defoliation were lower than that of healthy. It may be shown that the freezing hardiness of defoliation and weakness were weaker than that of healthy.

• Animal Systematics, Evolution and Diversity
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• v.30 no.1
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• pp.1-8
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• 2014

The Dryopidae (Coleoptera) is composed of approximately 300 species worldwide belonging to 33 genera; however, members of the family have not been recorded in Korea. We collected and recorded adult specimens of Elmomorphus brevicornis Sharp (=E. brevicornis brevicornis Sharp) on piles of submerged twigs and branches of a decayed tree (Prunus sp.) from a mountain stream in southwestern Korea with a comparison of the type specimens of E. brevicornis amamiensis Nomura from Japan. Both of the subspecies are raised to the species level herein. Redescription, photographs, line drawings of diagnostic characteristics, distribution map, habitat, and taxonomic notes for Elmomorphus brevicornis are provided.

• Korean journal of applied entomology
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• v.41 no.4
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• pp.305-311
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• 2002

Asiacornococcus kaki (Kuwana) known as a serious pest on Diospyros kaki Thunb. has been reported erroneously as Eriococcus lagerstroemiae Kuwana. These two species were redescribed and illustrated for correct identification by the morphological characters of adult females with known host plants. Asiacornococcus Tang & Hao is a newly known genus from the Korean Peninsula.

• Korean journal of applied entomology
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• v.35 no.2
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• pp.137-139
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• 1996

The sycamore lace bug, Corythucha ciliata (Say), attacking a sycamore tree, Platatanus orientalis L., was first found in Korea, and was widely distributed in the central part of the country. The adult was milky white in color and 3.0-3.2 mm long, and the matured nymph was black. Heavily infested trees appear yellowish white as a result of feeding by the nymphs on the under surface of leaves.

• Journal of Korean Society of Forest Science
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• v.79 no.3
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• pp.290-301
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• 1990

The 167 plus tree clones of Pinus koraiensis in clone bank planted in 1983 were investigated for time of flowering, rate of flowering, and number of flowering from 1986 to 1989. The results were as follows : 1) There were clones in the minority which do not cross in natural pollination between earlest flowering female clones and latest shedding male clones. 2) The rate of male flowering appeared less than rate of female flowering and received influence of genetic more than rate of female flowering. 3) The numbers of flowering in female and male flower were affected by small number of clones. 4) The flowering number for female strobili was not related to the flowering number of male flower. The 42 clones among 167 clone had not male flower. 5) The flowering number of 167clones were classified three groups in female flower and four groups in male flower by L.S.D 5% test. 6) The clones with abundant female and male flower were selected based on the component analysis. 7) As Based on flowering rate and number of female, the juvenile phase of plus tree clones appeared to be until four years after grafting ; the transition period appeared to be from five to seven years after grafting ; the adult phase appeared to begin from eight years after grafting, 8) The grafted trees of Pinus koraiensis appeared early flowerring about six years compared with seedling trees.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.419-427
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• 2013

The insecticidal activity of 124 plant essential oils and control efficacy of six experimental spray formulations (SF) containing 0.25, 0.5, 1, 2.5, 5, and 10% of the selected oils was examined against both nymph and adult of the citrus flatid planthopper, Metcalfa pruinosa using direct contact applications (leaf dipping and spray). Reponses varied according to dose (1,000 and 500 mg/L). When exposed at 1,000 mg/L for 24 h using leaf dipping assay, 19 essential oils showed strong mortality (100%) among 124 essential oils screened. At 500 mg/L, 100% mortality was observed in cinnamon technical, cinnamon green leaf, cinnamon #500, cassia tree, citronella java and pennyroyal followed by origanum, thyme white, grapefruit, savory, fennel sweet, aniseed and cinnamon bark showed considerable mortality (93.3-80%) against nymphs of M. pruinosa. The moderate mortality (73.3-60%) was found in thyme red, tagetes, calamus, lemoneucalptus and geranium. Oils applied as SF-10% sprays provided 100 % mortality against adult M. pruinosa. One hundred mortalities were achieved in cinnamon technical at >SF-0.5 formulation, in cinnamon #500, cinnamon green leaf and penny royal at >SF-2.5. To reduce the level of highly toxic synthetic insecticides in the agricultural environment, the active essential oils as potential larvicides could be provided as an alternative to control M. pruinosa populations.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.319-325
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• 2009

Woolly apple aphid, Eriosoma lanigerum, overwintered as adult or nymph stage on rootstocks, and crown- and root sucker in the soil. In an un sprayed apple orchard, the number of E. lanigerum colony started to increase from mid-April, showed the 1st peak between late June and early July, thereafter decreased followed by the 2nd peak in late July, and then again peaked in late September as the size in the 1st peak. In this orchard, the number of E. lanigerum colonies per tree did not exceed 3.5 colonies during the peak occurrence period, and was maintained around 2 colonies throughout seasons. In all seasons, parasitism of Aphelinus mali on E. lanigerum was much lower on root colonies than on aerial colonies that located on shoots and tree trunks above the ground. The parasitism of E. lanigerum was high in most orchards examined, showing parasitism of > 70% in maximum in most cases. In the laboratory bioassay for the mortality effects of several insecticides on E. lanigerum, fenitrothion, dichlorphos, machine oil, methidathion, thiacloprid, and imidacloprid showed 97.8, 96.8, 95.4, 91.5, 26.7, and 7.8% morality, respectively. Also, the adult emergence rates from A. mali mummies were 51.2, 72.6, 14.2, 3.5, 72.2, and 85.4% in the treatment of the above insecticides, respectively. Insecticides belong to neonicotinoid, which are newly developed to control aphids, showed low mortality against E. lanigerum. Fenitrothion and dichlorphos were effective on E. lanigerum control and had a low toxic to A. mali. Consequently, the insecticides should be useful in integrated pest management system for E. lanigerum in apple orchards.

• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.361-368
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• 2016

Japanese pine sawyer (JPS), Monochamus alternatus is a vector insect of pine wood nematode, Bersaphlenchus xylophilus in Korea and Japanese pine forest. This study was to evaluate the possibility of biological control of JPS with Korean entomopathogenic nematodes (EPNs). Korean EPNs (Heterorhabditis sp. Gyeongsan, Steinernema carpocapsae GSN1, S. glaseri Dongrae and S. longicaudum Nonsan strain) were infested bate insect, Galleria mellonella in log of dead pine tree. Result showed that, S. carpocapsae GSN1 strain has the highest pathogenicity. Heterorhabditis sp. Gyeongsan and S. carpocapsae GSN1 had infested bate insect, which located in 7.5 cm depth of pine log. EPN has pathogenicity against larva and adult of JPS. Spray application of EPNs against adult of JPS, Heterorhabditis sp. Gyeongsan strain showed higher pathogenicity than S. carpocapsae GSN1 strain. EPN infested larva of JPS was detected on bark spray treatment with S. carpocapsae GSN1 strain in dead pine log that naturally infested larva of JPS however, no EPN infested JPS was detected on soaking of pine log with suspension of S. carpocapsae GSN1 strain. Though EPN had found with low efficacy against JPS but still possible to apply to control the boring insect pest as they can control log dwelling insect.

• Parasites, Hosts and Diseases
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• v.54 no.1
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• pp.109-112
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• 2016

We performed a molecular genetic study on the sequences of 18S ribosomal RNA (ITS1 region) gene in 4-day-old adult worms of Macroorchis spinulosus recovered in mice experimentally infected with metacercariae from crayfish in Jeollanam-do Province, Korea. The metacercariae were round, $180{\mu}m$ in average diameter, encysted with 2 layers of thick walls, but the stylet on the oral sucker was not clearly seen. The adult flukes were oval shape, and $760-820{\mu}m$ long and $320-450{\mu}m$ wide, with anterolateral location of 2 large testes. The phylogenetic tree based on ITS1 sequences of 6 M. spinulosus samples showed their distinguished position from other trematode species in GenBank. The most closely resembled group was Paragonimus spp. which also take crayfish or crabs as the second intermediate host. The present study is the first molecular characterization of M. spinulosus and provided a basis for further phylogenetic studies to compare with other trematode fauna in Korea.

• Korean journal of applied entomology
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• v.48 no.2
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• pp.159-164
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• 2009

A taxonomic review of a new record, Bolitophagiella pannosa (Lewis) in Korea is presented. Description of adult is presented and also we conducted laboratory and field observations of the life history and fungal hosts of the darkling beetle, Bolitophagiella pannosa (Lewis). A fungivorous tenebrionid beetle, Bolitophagiella pannosa (Lewis), was a rare inhabitant of fungi on deciduous trees (Quercus, Robinia pseudoacacia etc.) in Korea. Development from egg to adulthood took 3${\sim}$10 months in nature and about 54 days in the laboratory at 25.5${\sim}$$26.1^{\circ}C$ and 63.5${\sim}$64.5% relative humidity. Both larvae and adults overwintered in their host fungi or beneath the bark of the host tree near the host fungi. Sporophores of Perenniporia medulla-panis (Fr.) Donk and Perenniporia frazinea (Fr.) Ryv. were obligate feeding and breeding sites in Korea. Description, habitus photographs of adult and instar, and illustrations of diagnostic characters are provided.