• Proceedings of the Korean Society of Crop Science Conference
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• 1998.10a
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• pp.415-445
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• 1998

For effective prevention of the spreading and outbreak of crop insects and disease pests, an intensive Pest surveillance system was established to predict their density changes, and distribution. After their initial establishment by either immigration or overwintering, it is necessary to anticipate how they spread out geographically and predict where/when outbreaks are possible. The two major tools, boundary layer atmospheric model (Blayer) and the geographic information system(GIS), have been being developed to facilitate the prediction of pest occurrence in recent days. We are also developing the PeMos (Pest Monitoring System) that is able to manage the pest surveillance data collected from 152 pest monitoring stations in Korea. These three system related to the pest surveillance should be integrated into an internet based comprehensive database management system to facilitate information resources systematically organized and closely linked. Considering various data types and large data size in each system, a new special information management system is suggested. The integrated system should express complex types of information, such as text, multimedia, and other scientific data under the Internet environment. This paper discussed the major three systems, GIS, Blayer, and PeMos, relevant to the crop pest surveillance, then how they can be integrated in a comprehensive system under the Internet environment.

• Journal of Korean Society of Forest Science
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• v.12 no.1
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• pp.59-63
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• 1971

In the light of the fact that Cryptorrhynchus lapathy Linne (Coleoptera: Cur-culionidae) is an important past of poplar in korea the Bionomics of the insect were studied to get some basic informations for controlling the insect. The results obtaind are as follows; 1. The poplar and willow borer has one generation in a year overwintering with egg. 2. The pupation stage was from the middle Julne to the middle July. 3. The adult appears from the early July to the middle August. 4. The average length of body of adult was about 8.5cm with female, 7.9cm with male and the length of pupa was about 11.3cm. 5. The average longevities of adults were about 30 days with mate and 40 days with female. 6. The length of damage hole were about 10.3cm. 7. The egg-laying period was from July to August.

• International Journal of Industrial Entomology and Biomaterials
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• v.43 no.2
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• pp.37-44
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• 2021

Mulberry silkworm is classified into uni, bi and multivoltine based on the frequency of diapause incidence. The variation in the incidence of diapause in bivoltine silkworm provides a unique opportunity to study the process of evolution of adaptive plasticity towards seasonal variations. The diapause expression in bivoltine silkworm is highly variable and is determined by environmental factors experienced by the maternal generation. Diapause in natural populations is functionally associated with the overwintering mechanism that facilitates survival in harsh winter conditions. In contrast, under standard commercial rearing conditions, the domesticated bivoltine silkworm is known to enter diapause in every generation. This paper presents a short review of the literature dealing with the role of temperature, photoperiod, diapause hormone and its receptor in diapause induction. Also, we briefly review the incidence of non-diapause eggs in bivoltine silkworm under controlled conditions.

• The Plant Pathology Journal
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• v.39 no.4
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• pp.374-383
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• 2023

Capsicum annuum (CA) is grown outdoors across fields in Jeollabuk-do, South Korea. The weeds surrounding these fields were investigated regarding the infection of 11 viruses infecting CA during the year 2014-2018. In the reverse transcription polymerase chain reaction diagnosis, 546 out of 821 CA samples (66.5%) were infected by nine viruses, and 190 out of 918 weed samples (20.7%) were infected by eight viruses. Correlation analysis of the mutual influence of the viruses infecting CA and weeds during these 5 years showed that five viruses had significant positive correlations with the infection in both CA and weeds. Over the study period, the weeds infected by cucumber mosaic virus (CMV) in the previous year were positively correlated with the incidence of CMV infection in CA in the current year, although the correlation was lower for tomato spotted wilt virus (TSWV) compared to CMV. The CMV infection percent was 14.0% in summer annuals, 11.4% in perennials, and 7.8% in winter annuals. However, considering the overwintering period without CA, the infection percent was 5.2% higher in winter annuals and perennials than that in summer annuals, indicating that winter annual and perennial weeds served as the main habitats for insect vectors. The TSWV infection percent in weeds was 10.4% in summer annuals, 6.4% in winter annuals, and 6.2% in perennials. The weeds surrounding CA fields, acting as the intermediate hosts, were found to be the potent sources of infection, influencing the spread and diversity of CA-infecting viruses. The results of this study can contribute to prevent viral infection in agricultural fields.

• The Plant Pathology Journal
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• v.40 no.1
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• pp.83-97
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• 2024

Fusarium graminearum, the causal agent of Fusarium head blight (FHB) in cereal crops, employs the production of sexual fruiting bodies (perithecia) on plant debris as a strategy for overwintering and dissemination. In an artificial condition (e.g., carrot agar medium), the F. graminearum Z3643 strain was capable of producing perithecia predominantly in the central region of the fungal culture where aerial hyphae naturally collapsed. To unravel the intricate relationship between natural aerial hyphae collapse and sexual development in this fungus, we focused on 699 genes differentially expressed during aerial hyphae collapse, with 26 selected for further analysis. Targeted gene deletion and quantitative real-time PCR analyses elucidated the functions of specific genes during natural aerial hyphae collapse and perithecium formation. Furthermore, comparative gene expression analyses between natural collapse and artificial removal conditions reveal distinct temporal profiles, with the latter inducing a more rapid and pronounced response, particularly in MAT gene expression. Notably, FGSG_09210 and FGSG_09896 play crucial roles in sexual development and aerial hyphae growth, respectively. Taken together, it is plausible that if aerial hyphae collapse occurs on plant debris, it may serve as a physical cue for inducing perithecium formation in crop fields, representing a survival strategy for F. graminearum during winter. Insights into the molecular mechanisms underlying aerial hyphae collapse provides offer potential strategies for disease control against FHB caused by F. graminearum.

• Korean journal of applied entomology
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• v.47 no.3
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• pp.303-308
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• 2008

An unidentified moth was captured in sex pheromone traps of the oriental fruit moth, Grapholita molesta, especially at spring season in apple orchards and their vicinity. Though the captured males were similar in appearance to G. molesta males, they were easily distinguished by a matted difference in body size. Their occurrence pattern was also similar to that of overwintering G. molesta population from April to May, at which more males were captured in the pheromone traps installed in the vicinity of apple orchards than within apple orchards. After May, they were no longer captured in the pheromone traps. To investigate any larval damage due to this unidentified moth, molecular markers needed to be developed. Four PCR-RFLP markers originated from cytochrome b region of mitochondrial DNA could distinguish this unidentified moth from G. molesta.

• The Korean Journal of Ecology
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• v.24 no.6
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• pp.377-380
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• 2001

Herbivory is an important selective forces on plants by reducing the ability of the plant to compete with its neighbors and to produce offspring. Oak nut weevil(Mechoris ursulus Roelofs) females lay eggs in unmatured acorns and cut off the branch of oviposited acorns. To investigate the influences of branch-cutting behavior of oak nut weevils on oak production, we surveyed the horizontal and vertical distribution ranges of damaged oaks and depth of sites of overwintering larvae and quantified the amounts of biomass and acorn removed by the weevils on deciduous oak species. All of the endemic oak species in Korea were damaged by oak nut weevils in all of the study sites including Mt. Halla and Mt. Seorak. The upper limit of vertical distribution of damaged oaks by the weevils raried from 700 m to 900 m. Mostly their larvae were found in soil from 8.1 cm to 10.0 cm depth in winter. Percentage of annual net primary productivity($720g{\cdot}m^{-2}{\cdot}day^{-1}$) of oak species removed by the weevils was about 7%, which is higher than the percentage removed by all the herbivores in typical temperate forest(5%) and equivalent to that by all the herbivores in tropical forest. The predation percentage of annual acorn production by oak nut weevil was 27% in Q. mongolica and 33% in Q. acutissima. This results indicate that the branch-cutting behavior of oak nut weevil may be the most important factor regulating oak population and affecting other predators dependent on acorns.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.2
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• pp.117-122
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• 1997

This experiment was conducted to evaluate the forage yield and quality and the possibility to provide Festulolium bmunii(Festuca pratensis $Huds{\times}Lolium$ mult~jlotum Lam.) as forage source in Korea. The Festuloliurn braunii were harvested at boot, heading and anthesis stage, respectively. The field trials were performed 6om 1994 to 1996 at the forage experimental field, College of agriculture, Chunpam National University. The results obtained were summarized as follows: 1. The date of boot, heading and anthesis stage of Festulolium bmunii observed in Taejon were May 12, May 23 and June 1 in 1995, and June 1, June 4 and June 9 in 1996, respectively. Winter survival percentage of Festulolium bmunii war ranged 6om 96% to 98% and summer survival percentage were 75-86%. It would suggest that Festulolium brawlii persisted well in the aspect of overwintering, while it wasn' t widely adapted to drought and high temperature in Taejon regions. 2. The CP content and DMD of Festulolium bmunii tended to decline as the growth stage advanced. The CP content and DMD of Festulolium bmunii were high at the boot stage and those at the anthesis stage were low. But fiber contents at the boot stage were lower than those at anthesis stage(P< 0.05). The yields of the DM and DDM with advancing the growing stage tended to increase, while there was no difference in the CPDM yields among stages. On the otherhand, the yields of DM and DDM at the anthesis stage were the highest (P< 0.05), but there was no difference in CPDM yield among stages. Based on the results mentioned above, it is suggested that Festulolium b m n i i has a possibility to use until the anthesis stage under the cutting regimes and that it has a potentiality to provide one of a good forage sources. %'ifqqiZ 43q *(College of Agriculture, Chungnam National Un~versity, Taejon 305-764, Korea)

• The Plant Pathology Journal
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• v.27 no.4
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• pp.324-332
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• 2011

Soil-borne barley yellow mosaic disease caused by Barley yellow mosaic virus (BaYMV) or Barley mild mosaic virus (BaMMV) gives a serious threat to the winter barley cultivated in the southern regions in Korea. It is important to develop resistant varieties for stable and high-yield production. The objectives of this study were to evaluate 22 genotypes of exotic barley germplasms carrying the resistance genes rym1 through rym12, with the exception of rym10, and to determine the genes that confer resistance to BaYMV or BaMMV in Korea. Using the traditional visual scoring of symptoms at 4 locations over 3 years, average disease rate values differed (P < 0.001) among the genotypes. ELISA test revealed the presence of both BaYMV and BaMMV in all of the field sites but Jinju and significantly different rates of infection among genotypes and years. Barley genotypes differed in how virus quantities and pathogen-induced symptoms were correlated, especially in response to BaYMV. Disease incidence was affected by the climatic conditions present during the early growing stage before overwintering. A Chinese landrace, 'Mokusekko 3', carrying rym1 and rym5 was comparatively resistant at all locations studied. The barley genotypes carrying either rym6 or rym9 were susceptible to the viral strains. The genotypes carrying rym5 were resistant in Jinju and Milyang but susceptible in Iksan and Naju. The resistance genes rym2 and rym3 were effective in local strains and would be potent contributors to disease resistance.

• Korean Journal of Plant Tissue Culture
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• v.27 no.4
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• pp.339-343
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• 2000

When plants are exposed to subfreezing temperatures ice crystals are forming within extracelluar space in leaves. The growth of ice crystal is closely related to the degree of freezing injury. It was shown that an antifreeze protein binds to an ice nucleator through hydrogen bonds to prevent growth of ice crystal and also reduces freezing damage. The antifreeze proteins in plants are similar to PR proteins but only the PR proteins induced upon cold acclimation were shown to have dual functions in antifreezing as well as antifungal activities. Three of the genes encoded for CLP, GLP, and TLP were isolated from barley and Kentucky bluegrass based on amino acid sequence revealed after purification and low temperature-inducibility as shown in analysis of the protein. The deduced amino acid of the genes cloned showed a signal for secretion into extracellular space where the antifreezing activity sup-posed to work. The western analysis using the antisera raised against the antifreeze proteins showed a positive correlation between the amount of the protein and the level of freeze tolerance among different cultivars of barely. Besides it was revealed that TLP is responsible for a freeze tolerance induced by a treatment of trinexapac ethyl in Kentucky bluegrass. Analysis of an overwintering wild rice, Oryza rufipogon also showed that an acquisition of freeze tolerance relied on accumulation of the protein similar to CLP. The more direct evidence for the role of CLP in freeze tolerance was made with the analysis of the transgenic tobacco showing extracellular accumulation of CLP and enhanced freeze tolerance measured by amount of ion leakage and rate of photosynthetic electron transport upon freezing. These antifreeze proteins genes will be good candidates for transformation into crops such as lettuce and strawberry to develop into the new crops capable of freeze-storage and such as rose and grape to enhance a freeze tolerance for a safe survival during winter.