• Molecules and Cells
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• v.26 no.2
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• pp.146-151
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• 2008

The brown planthopper (BPH) is a major insect pest in rice, and damages these plants by sucking phloem-sap and transmitting viral diseases. Many BPH resistance genes have been identified in indica varieties and wild rice accessions, but none has yet been cloned. In the present study we report fine mapping of the region containing the Bph1 locus, which enabled us to perform marker-aided selection (MAS). We used 273 F8 recombinant inbred lines (RILs) derived from a cross between Cheongcheongbyeo, an indica type variety harboring Bph1 from Mudgo, and Hwayeongbyeo, a BPH susceptible japonica variety. By random amplification of polymorphic DNA (RAPD) analysis using 656 random 10-mer primers, three RAPD markers (OPH09, OPA10 and OPA15) linked to Bph1 were identified and converted to SCAR (sequence characterized amplified region) markers. These markers were found to be contained in two BAC clones derived from chromosome 12: OPH09 on OSJNBa0011B18, and both OPA10 and OPA15 on OSJNBa0040E10. By sequence analysis of ten additional BAC clones evenly distributed between OSJNBa0011B18 and OSJNBa0040E10, we developed 15 STS markers. Of these, pBPH4 and pBPH14 flanked Bph1 at distances of 0.2 cM and 0.8 cM, respectively. The STS markers pBPH9, pBPH19, pBPH20, and pBPH21 co-segregated with Bph1. These markers were shown to be very useful for marker-assisted selection (MAS) in breeding populations of 32 F6 RILs from a cross between Andabyeo and IR71190, and 32 F5 RILs from a cross between Andabyeo and Suwon452.

• Korean journal of applied entomology
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• v.52 no.1
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• pp.45-51
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• 2013

Tropical plants of mango(Mangefera indica), dragon fruit(Hylocereus undatus), and atemoya(Annona cherimola ${\times}$ A. squamosa) are cultivated in Jeju, Korea. A pest survey on those tropical fruits was conducted from 2008 to 2011. Major pests of Mango were thrips, aphid, mealybug, and lepidoptera species. Thrips palmi and Scirtothrips dorsalis were the most important pests in mango fields. T. palmi mainly injured the leaf but S. dorsalis injured the leaf and fruit. Lepidoptera mango pests injured leaves but some larva of Adoxophyes honmai injured fruit surface around the stem. Aphid pests, Aphis gossypii and Myzus persicae, injured the shoots and Pseudococcus kraunhiae occurred on the stem and fruit. Ant species, A. gossypii, and S. litura, were important pests on dragon fruit. Ants and aphid occurred and injured the stem, flower, and fruit. Spodoptera litura larva severely injured the stem. Among the atemoya pests, S. litura and Homona magnanima caused severe damage.

• Korean Journal of Weed Science
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• v.30 no.3
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• pp.183-190
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• 2010

The objective of this study was to isolate a herbicidally active compound from curly dock (Rumex crispus), a native weed in Korea and to identify its' chemistry. The $GR_{50}$ value of methanol extracts which is determined by a seed bioassay using rapeseed (Brassica napus) seedlings was $935\;{\mu}g\;g^{-1}$. Activity-directed isolation of ethylacetate extract led to the isolation of ECDA fraction with $GR_{50}$ value $53\;{\mu}g\;g^{-1}$. Based on data of GC-MS, $^1H$-NMR and $^{13}C$-NMR, the chemical structure of ECDA was determined as 2H-furo[2,3-H]-[1]-benzopyran-2-one which is known as angelicin. The $GR_{50}$ values of angelicin to barnyardgrass (Echinochloa crus-galli), southern crabgrass (Digitaria ciliaris), and indian jointvetch (Aeschynomene indica) were 426, 66 and $216\;{\mu}g\;g^{-1}$, respectively. Our results suggest that angelicin could be used as a lead compound for the development of new herbicides.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.4
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• pp.201-209
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• 1982

In 1980, the abnormal low temperature was lasted during the late stage of rice growing season, thus low temperature injury occurred severely. The severity of the injury and nutrition absorption were investigated. The result obtained were summarized as follows: 1. It was considered that the severe low temperature injury of rice was caused by the low temperature and shorts of sunshine in the late growing season of rice, especially, the minimum air temperature which was lasted for a few days below critical reproductive growing temperature in the meiosis stage affected high the injury. 2. The low tmperature injury was lightened in the no nitrogen applied plot, and becoming severe with high nitrogen levels, but the balanced application of NPK lessened the low temperature injury. 3. The low temperature injury was more severe in Indica and Japonica hybrid than in Japonica cultivar, and the injury was shown as sterilizing, degraded spiklets, ill emerging of head and inhibition of nutrition absorption, etc. 4. Under the low temperature condition, $SiO_2$ content of rice plant was significantly reduced according to the increase of nitrogen levels. 5. Under the low temperature condition, the optimum application amount of nitrogen for Milyang 23, was 13, 6 kg/10a, this was approximately 10kg/10a smaller than average in usual year. The highly reduced rice yield was resulted from the cool injury, and the reducing rate of yield was larger in Indica and Japonica hybrid cultivar than in Japonica cultivar.

• Journal of Aquaculture
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• v.20 no.1
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• pp.1-6
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• 2007

Two feeding experiments were conducted to investigate the effects of fermented cactus fruit (Opuntia ficusindica) fluid (FCFF) as a feed additive to a commercial diet on the growth of red sea bream, Pagrus major, and to determine an effective dose. FCFF was prepared by mixing crushed cactus fruit with a starch solution and commercially available microorganisms for 2 weeks at room temperature. Three triplicate groups of red sea bream had initial mean weights of 84.1 g (Exp-1) and 5.1 g (Exp-2) and were fed experimental diets containing 0%, 1%, and 5% FCFF for 2 months (Exp-1) and 0%, 0.2%, 0.5%, and 1% FCFF for 3 months (Exp-2), respectively. In experiment 1, the mean body weight of fish fed the diet containing 1% FCFF was significantly higher (P<0.05) than that of fish fed the diet without FCFF. The survival rate was highest in fish fed the diet containing 1% FCFF, although the difference was not statistically significant. The feed gain ratio (FGR), specific growth rate (SGR), and condition factor (CF) values of fish fed the diet containing 1% FCFF were higher than those of fish in the other dietary groups that received lower levels of FCFF. The daily feeding rate (DFR) of fish fed the diet containing 1% FCFF was slightly lower but not statistically different than the DFR values of fish in the other dietary groups. In experiment 2, the final mean body weight of fish fed the diet containing 1% FCFF was significantly (P<0.05) higher than the mean weight of fish in the control group. The FGR, SGR, and CF values of fish fed the diet containing 1% FCFF were better than the values from fish in the other dietary groups that received lower levels of FCFF, although the differences were not statistically significant. However, the DFR of fish fed the diet containing 1% FCFF was lower than those of fish in the other groups. These results suggest that FCFF could be used as a feed additive in commercial fish food and a preferable level of supplementation is at least 1.0% in fingerling and young red sea bream.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.229-234
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• 1982

Environmental factors are known in general to influence much on the development of abscission layer and thereby on shedding of plant parts. The present study was carried out to determine the effect of meterological condition during ripening on the grain shatterability of rice plants at harvest. Different meteorological conditions were obtained by shifting transplanting timing of 40 days old rice seedlings 4 times with a 15 days-interval. Grain shatterability was measured as tensile strength of rice grains: it varied within a range of 214g. to 251g. in a practically non-shattering Japonica variety'Jinheung' and l27.5g. to 204g. in an easy shattering Indica \times Japonica progeny variety'Taeback'. In view of field loss of rice, the variation in tensile strength with time of transplanting and harvest did not matter in Jinheung, but was an important factor in Taeback. In Taeback the tensile strength was significantly correlated positively with mean, maximum and minimum air temperature and relative humidity during a certain period of grain ripening, especially during 30 days period before harvest, but diurnal range of air temperature showed a significant, negative correlation with it. The tensile strength seemed to be more closely related with min. air temperature than max. air temperature, and it was not significantly correlated with radiation amount during any period of pre-harvest. Meteorological effect on grain shatterability may vary with variety, but temperature regime during ripening appears to play major role among the meteorological factors in easy shattering and more thermophilic Indica \times Japonica varieties: lower the temperature, greater the shatterability.

• The Journal of Natural Sciences
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• v.14 no.1
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• pp.63-81
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• 2004

It is the purpose of this study to arrange in ornamental trees and shrubs the planting that leads to an appropriate type of templescape. The study was designed primarily as an examples for each Buddhist temple which desires further decoration with several ornamental plants, doubles the effectiveness of the Sen-Buddhist meditation, and boosts tourists' attraction. To investigate the planting status and type of trees and shrubs in the precincts of Buddhism temples, We close three temples : They are Nagsansa, Boolgoogsa and Booseugsa, which are intermonatane area temples all together. The results investigated were summarized as follows :1. Planting status and pattern in temples Open spaces of the Daewoogjeon in all temples, a main Sanctuaries in temple buildings, where Buddha is enshrined in, we could not find any kind of trees of shrubs to be planted.Muryangsujeon, a symbol of "Future", which can be also found at Boosugsa temple, is living in Western Elysium world and takes mercy on mankind of this life. Taxus cuspidata was planted at this Muryangsujeon, known as an immeasurable bliss building, where an Amitabha is enshrined in.Total 25 species of trees and shrubs were planted around Birozani building of Buddhist temples, Birozani is enshrined at the Birojion of Boollgoogsa temple.The buddhist Goddess of Mercy which is a buddhist saint for pursuit of fortune and blessing to relieve the mankind is enshrined at Wonchonjeon, Daebijeon and Kwaneumjeon which are able to observe at both Boolgoogsa and Nagsnsa temples, where Euonymus japonicus trees including other 26 species could be found in common at both temples.2. Correlation between trees/shrubs and temple buildingsTrees and flowers symbolizing Buddha are often planted as material sources of gardening to decorate : They are Logerstroemia indica as Buddha's flower, Viburmum opulus var. calvescens resembling Buddha's head, Tilia mandshurica producing the beads of rosary, Gardenia jaminoides Ellis with white flower blade and flower of bliss, not flower to this day and Lotus flowering clearly in the pond filling with dirty water which is able to clarifies the world full of crime, infidelity and injustification. Among these Buddhist' plants, however, Logerstroemia indica could be found in all three temples, and Viburmum opulus var. calvescens at both Nagsansa and Boosugsa. Also, Lager stroemia indica was planted at all three temples and Viburmum opulus var. calvescens at both temples of Nagsansa and Boosugsa. Tilia mandshurica and Gardenia jasminoides Ellis were not found in any temples which might become the subject of investigation.In relation of the buildings of each temples as a sanctified space, the planting of trees and shrubs was not considered for the arrangement, templescape architecture or species. And, also, we could not find in the study any special relationship of trees/ shrubs with the characteristics of temples.With the results obtained through precise studies we presented here in this paper newly designed model of templescape in intermane buddhist temple which can be applied for planting and arrangement of trees or/and shrubs. Basic principles of model in mind are:To consider the correlation of the dominant between plants and temple buildings.To plant trees/shrubs for special functions as well as conditions of temple location.To make tree arrangement correlating to Buddhism spirit.To induce environment friendly plants to be planted, suitable to regional conditions.This redecorated model of templescape might be used as a canon of the tree planting and arrangement in the precincts of Buddhism temples.

• The Korean Journal of Ecology
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• v.25 no.5
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• pp.305-313
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• 2002

The physico-chemical characteristics of water and sediment, and structures of vegetation of the vascular hydrophytes were investigated in the West Nakdong River. Water quality was eutrophic according to the mean values and the ranges of water properties such as pH, DO, BOD, chlorophyll a, total nitrogen and phosphate, and other nutrients. A few cases were hypereutrophic for chlorophyll a level in summer. Soil reaction was weak acid. Composition of sediment was mainly sand except in SI(Sinan chideung) of which was mainly clay, and SU(Suan chideung) of which was mainly silt. Flora of vascular hydrophyte had 26 species and 1 variety comprising 16 families. Trapa japonica was dominant species in the sites of DU(Dunchido), GA(Garak chideung) and SU. Nymphoides peltata and Hydrocharis dubia dominated in DA and SI, respectively. Species diversity and evenness were relatively high in SI and SU but dominance was high in DA. After June, water lettuce(Pistia stratiotes) and water hyacinth(Eichhornia crassipes) were flowed from tributary to the river. Standing crop of macrohydrophytes was high in DA from April to August, but it showed maximum standing crop (445g·dw/㎡) in DU after disturbance by explosive growth of exotic plants in October. In comparison with those in 1985, total productivities in DU and GA decreased to 33.5%, and the reduction ratio of dominant species, Trapa japonica was 56.7%. Najas marina, N. minor, Myriophyllum spicatum and Nymphoides indica have disappeared ever since the Nakdong barrage was constructed in the Nakdong river. They were divided into three groups (GA-SU-DU, DA, SI) by cluster analysis. Introduction of the exotic species in this river caused decreasing of endemic plants including endangered species Euryale ferox and rare species Hydocharis dubia, and food plants for waterfowl such as Trapa japonica, Vallisneria asiatica and Potamogeton crispus.

• Research in Plant Disease
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• v.13 no.3
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• pp.183-190
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• 2007

308 isolates of Ampelomyces quisqualis were isolated from powdery mildew fungi of 73 plant species in Korea from 1994 to 2004. Among them, the new mycohosts and new plant hosts of A. quisqualis were found in 13 species of powdery mildew fungi in 38 species of plant. The new hosts of A. quisqualis were Erysiphe heraclei on Heracleum moellenderfii; E. hommae on Elsholtzia splendins; E. glycines on Glycine max; E. lespedezae on Lespedeza biclor; E. pileae on Pilea mongolica; E. pisi on Phaseolus radiatus; E. polygoni on Rumex aquatica and Rumex crispus; Golovinomyce artemisiae on Artemisia princeps var. orientalis; G. cichoracearum on Rudbeckia laciniata var. hortensis; G. rubiae on Rubia akane; Oidium sp. on Valeriana fauriei, Lactuca indica var. laciniata, Carpesium triste var. manshuricum, Aster ageratoides var. turczaninow, Lufa cylindrica, Ixeris demtats Nakai, Phlox paniculata, Bidens bipinnata and Pathenocissus tricuspidata; Microsphaera alphitoides on Quercus aliema, M. pseudolonicerae on Cocculus trilobos; Podosphaera sp. on Ligustrum obtusifolium; Sphaerotheca aphanisi on Fragaria ananassa; S. balsaminae on Impatiens textori; S. fusca on Cucurbita pepo, Cucurbita maxima, Ligularia fischeri, Solanum melongena, Lagenaria leucantha, Cucumis melo var. makuwa, Acalypha australis, Cosmos bipinnatus and Aster scaber; Uncinuliella simulans on Rosa muliflora and Uncinula australiana on Lagerstroemia indica.

• Korean Journal of Weed Science
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• v.18 no.1
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• pp.28-35
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• 1998

Cyhalofop/bentazon ME and pyribenzoxim EC herbicides were originally developed as foliarapplied herbicides to control weeds at 4-5 leaf stages of barnyard grass 20-25 days after seeding (DAS) in direct-seeding culture but further possible utilization of these two herbicides earlier than 3-4 leaf stages of rice were evaluated for a field where early weed infestations might be severe. The application of cyhalofop/bentazon ME and pyribenzoxim EC at right after rice emergence and the 2-3 leaf stages of rice had an excellent weed control efficacy with above 90% up to 30 DAS without a phytotoxicity of rice plant and the control efficacy of over 80% was maintained until 60 DAS. However, these two herbicides controlled Echinochloa crus-galli very effectively above 97% but Aneilema keisak and Aeschynomene indica were not controlled by cyhalofop/bentazon ME and Cyperus serotinus by pyribenzoxim EC. Therefore, to control those problem weeds, second systematic application of pyribenzoxim EC and pyrazosulfuron/mefenacet G for A. keisak and A. indica, and pyrazosulfuron/molinate G, cyhalofap/ azimsulfuron/molinate G, pyrazosulfuron/mefenacet G and bentazon SL for C. serotinus at 30 DAS was found to be very efficient herbicide systems.