• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.4
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• pp.281-286
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• 2009

Introduction: Enamel matrix derivative (EMD) is a protein which is secreted by Hertwig root sheath and plays a major role in the formation of cementum and attachment of peridontium. Several studies have shown that EMD promoted the proliferation and differentiation of preosteoblasts, osteoblasts and periodontal ligament cells in vitro: however, reports showing the inhibition of osteogenic differentiation by EMD also existed. This study was designed to simultaneously evaluate the effect of EMD on the two cell lines (human mesenchymal stem cells: hMSC, human periodontal ligament derived fibroblasts: hPDLCs) by means of quantitative analysis of some bone related matrices (Alkaline phosphatase : ALP, osteopontin ; OPN, osteocalcin ; OC). Materials and Methods: hMSCs and hPDLCs were expanded and cells in the 4${\sim}$6 passages were adopted to use. hMSc and hPDLCs were cultured during 1,2,7, and 14 days with 0, 50 and 100 ${\mu}g/ml$ of EMD, respectively. ALP activity was assessed by SensoLyte ALP kit and expressed as values of the relative optical density. Among the matrix proteins of the bony tissue, OC and OPN were assessed and quantification of these proteins was evaluated by means of human OC immunoassay kit and human OPN assay kit, respectively. Results: ALP activity maintained without EMD at $1,2^{nd}$ day. The activity increased at $7^{th}$ day but decreased at $14^{th}$ day. EMD increased the activity at $14^{th}$ day in the hPDLCs culture. In the hMSCs, rapid decrease was noted in $7^{th}$ and $14^{th}$ days without regard to EMD concentrations. Regarding the OPN synthesis in hPDLCs, marked decrease of OPN was noted after EMD application. Gradual decrease tendency of OPN was shown over time. In hMSCs, marked decrease of OPN was also noted after EMD application. Overall concentration of OPN was relatively consistent over time than that in hPDLCs. Regarding the OC synthesis, in both of hPDLCs and hMSCs, inhibition of OC formation was noted after EMD application in the early stages but EMD exerted minimal effect at the later stages. Conclusion: In this experimental condition, EMD seemed to play an inhibitory role during the differentiation of hMSCs and hPDLCs in the context of OC and OPN formation. In the periodontium, there are many kinds of cells contributing to the regeneration of oral tissue. EMD enhanced ALP activity in hPDLCs rather than in hMSCs and this may imply that EMD has a positive effect on the differentiation of cementoblasts compared with the effect on hMSCs. The result of our research was consistent with recent studies in which the authors showed the inhibitory effect of EMD in terms of the differentiation of mineral colony forming cells in vitro. This in vitro study may not stand for all the charateristics of EMD; thus, further studies involving many other bone matrices and cellular attachment will be necessary.

• Korean Journal of Poultry Science
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• v.37 no.2
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• pp.131-137
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• 2010

The present study has been performed to suggest a method to decrease the adverse effects of transportation on chicken meat quality. The groups were prepared as follows; Control group and three groups of treatments (sodium phosphate, sodium bicarbonate and magnesium sulfate). The chicken fed magnesium sulfate showed higher chicken meat quality compared to control and other treatment groups. Also, minor and severe PSE incidence of chicken breast was found at 88% in sodium phosphate group, 24% in sodium bicarbonate group and 56% in magnesium sulfate group. Control group showed 92% higher minor and severe PSE incidence of chicken breast compared to other groups. In control group, the external bruise of chicken showed 32% but 22, 24 and 44% in other treatment groups, respectively. Lightness ($L^*$) of chicken containing sodium phosphate treatment, sodium bicarbonate treatment and magnesium sulfate were 67.05, 66.27 and 65.89, while Lightness ($L^*$) of chicken containing control group was decreased of 67.88. In conclusion, dietary buffer material (sodium phosphate, sodium bicarbonate, magnesium sulfate) under heat stress decreased adverse effects including death, wound or abnormality of chickens.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.146-150
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• 2006

도축 후 2일째 가열 감량은 시험구(골반골 현수)가 대조구(아킬레스건 현수)에 비하여 유의적으로 감량이 높았으나, 드립량에 있어서는 반대의 결과를 보였으며, 전체 감량은 두 처리구간 차이가 없었다. 연도의 지표인 전단력가는 대조구 $6.45kg/cm^2$로 시험구 $5.52kg/cm^2$에 비하여 유의적으로 높았으며, 골반골 현수를 통하여 도축 후 8일차의 대조구의 전단력 수준을 보여 숙성기간을 약 1주일 정도 단축이 가능하였다. 근절길이는 대조구 $1.93{\mu}m$, 시험구 $2.48{\mu}m$로 시험구가 유의적으로 길어 골반골 현수에 의한 단축 억제 효과로 볼 수 있다. 관능 평가 결과 도축후 2일차에는 대조구에 비하여 시험구가 다즙성, 연도, 향미, 기호성에서 유의적으로 높은 값을 보였으나, 도축 후 8일째에는 대조구와 시험구간에 차이를 보이지 않았다. 출하 연령과 현수방법에 따른 대퇴이두근의 물리적 특성을 비교한 결과로서 근절길이는 모든 월령에서 시험구가 대조구에 비하여 길었다. 전단력은 시험구가 대조구에 비하여 유의적으로 낮은 결과를 보였다. 골반골 현수에 의한 전단력가 감소 효과는 출하 월령이 많을수록 효과가 큰 것으로 나타났다. 드립 발생율은 대조구가 시험구에 비하여 유의적으로 높은 경향을 보였다. 가열 감량과 보수성은 처리구에 관계없이 유의적인 차이를 보이지 않았다. 관능 특성을 비교한 결과 30개월 미만의 경우에는 유의적인 차이를 보이지 않았으나, 30개월 이상에서는 처리구가 대조구에 비하여 다즙성 연도, 향미, 기호성 모두 우수한 것으로 나타났다. 특히 골반골 현수는 출하 월령이 증가됨에 따라 관능 특성의 개선율이 높은 것으로 나타났다. 수 있다.분별을 성공적으로 수행하였다.(p<0.05), 맛, 연도, 다즙성 및 전체적인 기호성은 유의한 차이가 없었다.자체를 악하다고 볼 수 없고 더구나 구원을 이 세상에서의 이탈로 볼 수 없다. 진정한 구원이란 원래 하나님이 보시기에 아름다웠던 그 세상으로의 회복을 포함한다. 이런 면에서 하나님 주권 신앙 하에서 구원이란 전 인격적인 구원, 전 우주적인 구원이 된다. 그렇기 때문에 성도는 세상의 삶과 학문, 예술, 정치, 경제, 사회를 포함한 모든 분야를 하나님의 뜻 가운데서 그 원래의 목적에 부합할 수 있도록 회복시키는 일에 적극 참여해야 한다.자체가 이를 주도하기는 사실 어려움이 있다. 그리고 대형유통점이 영업행위를 영업시간제한에서부터 출점제한에 이르기까지 규제하는 건은 심사숙고하여야 한다. 대형유통점이 국가경제 및 지역사회에 미치는 영향이 부정적인가 긍정적인가에 대해 국내외 학계와 업계에서 여전히 많은 논란이 있기 때문이다. 정부와 지자체에 의한 시장개입은 반드시 필요한 경우에 한해 합당한 방법에 의해 이루어져야 한다. 대형유통점에 대한 규제는 지역사회에 미치는 영향을 다면적으로 평가한 결과에 근거하여 이루어져야 할 것이다. 대부분의 지자체는 체계적인 평가시스템과 객관적인 통계 자료를 갖고 있지 못한 실정이다. 향후 가장 시급한 과제는 시장개방 이후 지난 10년간 대형유통점이 지역사회에 미친 영향에 관한 광범위한 통계자료를 수집하고 이를 체계적으로 분석하여 정책방향을 올바르게 설정하는 것이라 할 수 있다.i와 K. pneumoniae가 존재하며 확산 중임을 시사한다. 앞으로 CTX-M형 ESBL의 만연과 변종 CTX-M형 ESBL의 출연을 감시하기 위한 정기적인 연구와 조사가 필요한 것으로 생각한다., A2-1, B1-1, B2-1의 경우,

• Korean Journal of Food Science and Technology
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• v.13 no.3
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• pp.171-175
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• 1981

Hand deboned and mechanically deboned chicken meat were produced from domestic broilers and spent layers. Meat yield, chemical composition, functional characteristics, storage stability and microbiogical properties were investigated. The results obtained were as follows: 1. 35% of carcass freight was recovered primarily as hand deboned chicken meat (HDM) and 45% secondarily as mechanically deboned chicken meat(MDM), total meat yield reaching 80% of carcass weight. 2. Moisture, protein, fat. ash and calcium content of MDM were 65, 12, 20, 1.7 and $0.2{\sim}0.4%$, respectively MDM was higher than HDM in fat, ash and calcium, but significantly lower in moisture and protein Total pigment content of MDM was 2.5 times higher than that of HDM, such high content being attributed to the increased inclusion of hemoglobin during the mechanical masceration of carcass in the deboning process. 3. The emulsifying capacity (ES) of MDM per g meat was only 70% that of HDM, but when ES was expressed on unit g of protein basis MDM showed even higher ES than HDM primarily due to the higher proportion of salt soluble protein fraction of MDM. 4. Since the TBA value of MDM increased rapidly after 4 weeks of frozen storage at $-20^{\circ}C$, the maximum possible storage period of MDM is estimated to be about 4 weeks. 5. Total microbial counts of MDM was approximately $1.8{\times}10\;cells/g$ showing no great difference from HDM or red meat.

• Journal of Animal Science and Technology
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• v.53 no.4
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• pp.367-375
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• 2011

This study was carried out to investigate the effects of the level of cracked whole barley on daily feed intake, daily body weight gain, carcass characteristics and meat composition of finishing Hanwoo steers (feeding from 24 months to 30 months of age). The dietary treatments were consisted of five types (C; normal concentrate as a basal diet, T1; 10% addition of cracked whole barley, T2; 20% addition of cracked whole barley, T3; 30% addition of cracked whole barley, T4; 40% addition of cracked whole barley). A total 30 Hanwoo steers (588.6${\pm}$11.8kg) were allocated to 5 feeding groups. The daily feed intake and daily body weight gain were high in the order of T2 > T3 >T4 > T1 > C. The back fat thickness and longissmus muscle area were highest in C and T1, respectively (P<0.05) than other treatments. The meat yield index decreased with increased back fat thickness. The marbling score and meat quality were highest in T1 (P<0.01, 0.05, respectively), but maturity, fat color and meat color were not significantly different among treatments. The crude fat was highest in T1 (17.59%), while in T4 (7.47%) it was lowest (P<0.05). The crude protein and crude ash were not significantly different among treatments. The energy value of cracked whole barley treatments (T1, T2, T3, T4) was higher than C (P<0.05). The contents of Ca, Cu, K, Mg, Mo, Na and Zn were higher in C than the other treatments (P<0.01), but Co was higher in T2 (P<0.01). The CIE $L^*$ value of whole cracked barley treatments (T1, T2, T3, T4) was higher than C, however there were not differences among the treatments. The CIE $a^*$ value was highest in T1(P<0.05) than others. The CIE $b^*$ value was highest in C and it was decreased with increased feeding of cracked whole barley. Based on the above results, T1 treatment compared to other treatments improved the carcass quality parameters like loin muscle area, marbling score, meat quality, and CIE $L^*$ value.

• KEPCO Journal on Electric Power and Energy
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• v.1 no.1
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• pp.39-46
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• 2015

A outdoor termination installed at the outdoor substation is required to connect undergroud cables and overhead transmission lines. The joint box for AC transmission system is already developed and widely used to interconnect overhead and undergroud systems. But the development of the joint box for DC transmission system was only introduced from China and Japan, but theire developemnt staus and core technologies were not fully reported. In order to implement HVDC systems connecting ovehead transmission lines and undergroud cables, a outdoor termination should be developed, but the detailed specifications and information of this device were not reported. It is estimated that the development of the joint box for DC environment has some technical obstacles including insulating materials, electric field mitigation, thermal temperature rise, and space charge accumuations. Among this, the most important one is the DC elctrical insualtion design. Therefore, in order to investigate the DC elctrical insualton design of outdoor termination, the design of AC slip-on type outdoor termination is reffered, and DC electric field analysis performed to verify the possiblity of application of AC joint box into DC joint box. Especially for DC electric field analysis, temperature rise of insualting materials of a joint box was considered, because the conductivity of materials could be changed due to temperature rise. Furthermore, DC electric field analysis considering transinet state, and polarity reversal state were also investigated to verify which state is the most severe condition for the DC joint box. From the simualtion resulsts, it was shown that the value and the position of maximum electric field was obtained comparing AC state, DC state without temperaure rise, and DC state with temperaure rise. And it was confimred that severe DC electric field was observed considing temperaure rise. Finally, in order to reduce DC eletric field intensifation, different configuration of the joint box was applied and it was not possible to obtain satisfactory results. It means that the slight change of configuration of AC joint box was not the suitable soluton for DC joint box. It is essential to establish novel DC insulaton design skills and method for DC joint box to commercialze this product in the near future.

• Journal of Animal Science and Technology
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• v.46 no.2
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• pp.165-172
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• 2004

This study was conducted to investigate changes in physico-chemical characteristics of Hanwoo carcass according to different castration and slaughtering ages. Total 75 Hanwoo calves(average 4 months old) were randomly assigned to Control(bulIs). Treatment I. Il , III. or IV(castrated on 4. 9. 12. and 16 months of age, respectively) and slaughtered at 7. 9. 12, 16, and 28 months of age. Moisture contents in M. Longissimus dorsi of both Hanwoo bulls and steers were decreased as the slaughtering age increased. Moisture contents in all steer groups were significantly(P <0.05) lower(average 68.63%) than that in bulls(72.18%) at 28 months of age. Crude fat contents tended to increase as the slaughtering age increased. Crude fat contents in Treatment III(castrated at 12 months of age) at 28 months of age were 10.24% which was the highest among all steer groups. Crude protein contents in M. Longissimus dorsi of Hanwoo bulls were around 23% regardless of slaughtering age. Water holding capacity(WHC) of both bulls and steers tended to increase as the animals aged. Steers showed rapid increase in WHC after 16 months of age and showed higher(78.39%)) WHC than bulls(70.00%) at 28 months of age. Palmitic acid(CI8: 0) contents in Hanwoo bulls were increased as the slaughtering age increased(20.92 \longrightarrow 24.22%) whereas stearic acid(CI8: 0) contents were decreased(I8.l5 \longrightarrow11.32%). Oleic acid(CI8: I). a major unsaturated fatty acid. significantly(P <0.05) increased(25.59 \longrightarrow 37.90%) when slaughtering age of Hanwoo increased. Changes in fatty acid composition in Hanwoo steers were similar to those in bulls except oleic acid contents were higher and stearic acid contents were lower than bulls at 28 months of age.

• Korean Journal of Agricultural Science
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• v.8 no.1
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• pp.51-63
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• 1981

The results of a crossbreeding experiment with a total of 315 litters and 325 pigs of Berkshires, Hampshires, Durocs, Landraces, Large Whites, eight different two-breed crosses and twelve different three-breed crosses, produced at Livestock Experiment Station from 1975 through 1979, are summarized as follows. 1. Number born alive per litter was largest in the D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ mating, followed by the D♂${\times}$(H♂${\times}$L♀) $F_1$ mating, and smallest in the Hampshires. The pigs in the 3rd-6th parities had larger litter size at birth than those in other parities. 2. Birth weight of pig was heaviest in L♂${\times}$Lw♀ mating and lightest in the Large White. The total litter weight at birth was heaviest in the D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ mating, followed by D♂${\times}$(H♂${\times}$L♀) $F_1$ ♀ and Lw♂${\times}$L♀ matings, and was smaller in Hampshires and Birkshires. 3. Litter size at weaning was largest in the D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ mating, followed by D♂${\times}$(H♂${\times}$L♀) $F_1$ ♀ and Lw♂${\times}$L♀ matings, and was smaller in Durocs and Hampshires. The pigs in the 3rd-6th parities had larger litter size at weaning than those in other parities. 4. The total litter weight at weaning was heaviest in the D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ mating, followed by H♂${\times}$(Lw♂${\times}$L♀) $F_1$♀ and Lw♂${\times}$L♀ matings, and was lighter in Durocs and Hampshires. The weaning weight of pig was largest in D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ mating and lightest in L♂${\times}$H♀ mating. 5. Survival rate at weaning was highest in L♂${\times}$Lw♀ mating, followed by D♂${\times}$(L♂${\times}$H♀) $F_1$ ♀ and D♂${\times}$(H♂${\times}$L♀) $F_1$ ♀ mating, and was lowest in Durocs. 6. The three-breed cross from D♂${\times}$(H♂${\times}$L♀) $F_1$ ♀ mating had the highest average gain and lowest feed requirement per unit gain, followed by the D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ and H♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ matings. The Birkshires and Landraces ranked lowest among the 25 mating groups compared for both of the traits. Males had higher average daily gain than females by about 0.06kg and had lower feed requirement by about 0.14. 7. The three-breed crosses from D♂${\times}$(H♂${\times}$L♀) $F_1$ ♀, D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ and H♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ matings reached 90kg body weight at younger age than the other groups. The D♂${\times}$(H♂${\times}$L♀) $F_1$ ♀ group reached 90kg at younger age than the Landrace by 39 days. 8. The dressing percentage and lean meat percentage tended to be higher in H♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀, H♂${\times}$L♀ and L♂${\times}$B♀ matings compared to the other mating groups. The loin-eye area was largest in the Lw♂${\times}$L♀ mating and smallest in the B♂${\times}$L♀ mating. Males had higher dressing percentage, higher lean meat percentage and lion-eye area than females. The backfat was thinnest in purebred Hampshire and was thickest in B♂${\times}$L♀ mating. 9. The results obtained in this study suggest that the two-breed cross from Lw♂${\times}$L♀ mating, and the three-breed crosses from D♂${\times}$(Lw♂${\times}$L-♀) $F_1$ ♀ and D♂${\times}$(H♂${\times}$L♀) $F_1$♀ matings are superior crossbreds for reproductive and pork prodnction performance.

• Journal of Animal Science and Technology
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• v.55 no.5
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• pp.451-460
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• 2013

The feed value of sesame meal, a main agricultural by-product from the northern area of Gyeongsangbuk-do province, was assessed in Hanwoo steers. A total of twelve Hanwoo steers (average BW = 412.08 kg) were allocated into a Control (fed no sesame meal) or Treatment (fed sesame meal from 14.6 months of age) group, considering BW and ages, and the animals were fed for a total of 480 days. The final BW, total gain and ADG for the Control and Treatment groups were 741.17 kg and 762.67 kg, 331.84 kg and 347.84 kg, and 0.69 kg and 0.72 kg, respectively, showing better performances in sesame meal-fed animals. Feed requirements during the whole experimental period improved by feeding sesame meal (15.31 and 14.87 for Control and Treatment group, respectively). Hanwoo steers fed sesame meal also showed a 22.83 kg heavier cold carcass weight (424.17 kg and 447.00 kg in the Control and Treatment group, respectively), and 2.41% improved dressing percentages (58.60% and 57.22% for the Control and Treatment group, respectively). The area of the M. longissimus dorsi was $91.83cm^2$ and $88.33cm^2$ in the Control and Treatment group, respectively. The final yield of A and B grade meat were 50 : 50% and 33.3 : 66.7% from the Control and Treatment group, respectively. The average marbling score was 4.83 and 5.50, and the numeric values for quality grade was 2.17 and 2.67 for the Control and Treatment group, respectively, showing better beef quality in sesame meal-fed Hanwoo steers. In fact, there were two animals with beef quality $1^{{+}{+}}$ in the sesame meal-fed group. The melting point of lipid extracted from the M. longissimus dorsi of Hanwoo steers was significantly (p<0.05) lower in the Treatment group ($28.28^{\circ}C$) compared to the Control group ($30.65^{\circ}C$). The composition of saturated fatty acids, $C_{14:0}$ (myristic acid) and $C_{16:0}$ (palmitic acid), were significantly lower in sesame meal-fed animals, 4.70% and 2.20% for myristic acid, and 30.55% and 27.12% for palmitic acid, in the Control and Treatment group, respectively. In contrast, there were no significant differences in C18:0 (stearic acid) composition between the groups. The composition of a representative unsaturated fatty acid, $C_{18:1}$ (oleic acid), was significantly higher in Treatment animals (49.89%) than Control animals (44.29%) (p<0.05). The ratio of total monounsaturated fatty acids / saturated fatty acids; M/S) was 1.10 and 1.36 for the Control and Treatment groups, respectively, showing remarkably higher ratios in sesame meal-fed group. The content of glutamic acid, related to beef flavor, was significantly higher in the Treatment group (3.35 mg/100 g) compared to the Control group (1.88 mg/100g) (p<0.05). The tenderness score, evaluated by an eight-point scale in the panel test, and overall palatability (based on juiciness, flavor, oiliness, and umami) were significantly higher in the Treatment group (5.67 and 5.23, respectively) than the Control group (3.83 and 4.60, respectively) (p<0.05). In conclusion, the current results imply that sesame meal could serve as a good supplement for Hanwoo steers for producing high quality beef.

• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.283-316
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• 1977

In an attempt to obtain a basic information to develop an effective integrated system of controlling sheath blight of rice in Korea, the transition of this disease, the variation of cultural characters and pathogenicity of the pathogen, environmental conditions affecting the disease outbreak and varietal resistance have been investigated. 1. Rice sheath blight which has been minor disease in the past was widely spread, especially since 1971. This disease has promptly spread all over the country and infected 65.2% of total rice growing area in 1976. Various factors are considered to be related to such transition of this disease. Above all, increace of application of nitrogenous fertilizer, early season and earlier cultivation of rice, introduction of more susceptible "Tongil" varieties etc. must be important factors influencing the outbreak of this disease. 2. Great variations in cultural characteristics-such as mycelial growth rate, color of the medium, amount of the aerial mycelium, shape and color of the sclerotia- and in the pathogenicity of isolates of the pathogen, Thanatephorus cucumeris Dank were observed. The optimum temperature for mycelial growth also varied with isolates, from $25^{\circ}C$ to $30^{\circ}C$. There were not necessarily any correlation between curtural characteristics and pathogenicity of isolates of Thanatephorus cucumens. 3. Mycelial grow th of isolates of Thanatephorus cucumens on the PDA medium were correlated with the air temperatures of the region where the isolates were collected. The isolates from the regions with high temperature grew well on PDA medium at $35^{\circ}C$ than those from the region with low temperature, on the other hand, the isolates from the regions with the low temperature grew well on the same medium at $12^{\circ}C$ than those from the regions with high temperature. 4. Pectin polygalacturonase (PG) and cellulase (Cx) were most active on the 3rd day after inoculation on the leaves of rice plant with Thanatephorus cucumeris, whereas pectin methylestrase (PE) was most active on the 4th day after inoculation. Relationship between the activities of PE of isolates and the strength of pathogenicity of isolates was obtained, but PG and cellulase activities were not correlated with pathogenicity of isolates. 5. The tolerence of sclerotia from in-vitro culture to low temperature varied with their water content, the dried cultural sclerotia were more tolerent than wet ones, Dried cultural sclerotia maintained almost 100% germinability for 45 days at $-20^{\circ}C$, whereas wet sclerotia lost viability at $-5^{\circ}C$. The germination ratio of the sclerotia after overwintering changed from 18% to 70% according to the water content of the test paddy fields and the ratio was low in wet paddy condition. 6. To investigate the host range of this fungi in and near paddy field, 17 weeds were inoculated with fungi. The lesions of sheath blight disease was obserbed on Sagittaria trifolia L., Echinochloa crusgalli P. Beauv., Monochoria vaginal is Presl, Polygonum Hydropiper L., Eclipta prostrata L., Digitaria sanguinalis Scapoli. 7. When the level of nitrogen applied was doubled over standard level, total nitrogen content in rice sheath increased, ami when silicate was applied, starch content in rice sheath decreased, inducing the rice plants more susceptible to sheath blight disease. Increased dressing of potash ferilizer reduced the incidence of sheat blight disease. 8. The percentage of infected stems in the early period increased more in the narrow hill plot than in the wide hill plot, but in the late period this tendency was inversed; the percentage of infected stems as well as severity in the wide hill plot increased more compared to the narrow hill plot, and the disease severity in the one plant per hill plot was also low. The number of stems in the wide hill plot was more than the number of stems in the narrow hill plot. This indicates that the microclimate, such as the relative humidity, in the narrow hill plot was more favorable for the development of this disease. 9. There was a high negative correlation between the disease severity of varieties to the sheath blight and the maturity of the varieties, that is, the early varieties were more susceptible than the late ones, and much-tillering varieties usually showed more infection than less tillering varieties. 10. No relationship was obtained between the percentage of infected stems in the early period and the severity after heading, whereas a distinct relationship was obtained between former and latter after Aug. 10.