The research aimed to develop a high-efficiency plate-type heat exchanger for exhaust gas using computational fluid dynamics (CFD) thermal analysis based on the plate shape, and to identify the optimal shape. Following this, a water/air plate heat exchanger was manufactured, and its characteristics were studied experimentally. As the Re number increases on the gas (or air) side, the heat transfer rate increases significantly, whereas an increase in the Re number on the water side leads to a smaller increase in heat transfer. This is attributed to the larger convective heat resistance on the gas side, causing a substantial reduction in gas-side heat resistance as gas velocity increases, resulting in a considerable overall reduction in heat resistance. The fluid flow pressure drop showed similar results between the CFD calculations and experimental outcomes.

This study was conducted to explain degree of injury caused by P. panopealis larva which is the key component to develop economic injury level or control threshold in green perilla and was carried out in polyvinyl houses at Yuseong Daejeon, Geumsan and Yesan Chungnam from 2004 to 2006. Of 5 major pests in green perilla polyvinyl house, P. panopealis larva injured green perilla leaf by 48.5% on average under no insecticides application. The peak occurrence of P. panopealis adult was early August and late September in 2004 and 2005 studies. The feeding amount of P. panopealis larva among 1st to 3rd instar was not different, but from the 4th instar the feeding amount greatly increased and this result was consistent with daily feeding experiment in which the amount greatly increased from seventh day. The degree of injury which was investigated with different larval infestation levels showed that the degree of injury increased a little but was not different significantly as the density increased. The density of P. panopealis larva in damaged green perilla plant was less than three individuals/plant. This result indicates that P. panopealis adult lays egg on green perilla leaf dispersedly and larva hatched from egg injures only the leaf which egg is layed. These preliminary data seems to be very useful to design economic injury level and control threshold studies for P. panopealis in green perilla polyvinyl house.

To control the pepper anthracnose caused by Colletotrichum acutatum, antifungal bacterium strains which was selected among bacterium from natural soil, was tested the antimicrobial activity against various pathogens and its control efficacy on anthracnose disease in the fields. We confirmed that antagonistic activity of CAB13001 strain to pathogens such as Sclerotinia cepivorum, Sclerotinia sclerotium and Botrytis cinerea including Colletotrichum acutatum was remarkable superior with the dual culture method in the artificial medium. In vitro bioassay using the green pepper fruit, CAB13001 strain suppressed the lesion development of Anthracnose disease, and its control value compared to the untreated one was 82.4% on pepper fruit in field test. These results suggested that CAB13001 strain could be a very useful biological control agents to anthracnose disease caused by air born plant pathogens of pepper. By the way, analysis of nucleotide sequence of the gene 16S rDNA, antagonistic bacterium CAB13001 strain used in this study was identified as Burkholderia lata.

Background : Polygonati rhizoma is used for medicine using rhizome of Polygonatum sibiricum Redoute belonging to Liliaceae. This study was carried out to select proper chemical for leaf spot disease control of P. sibiricum Redoute. Methods and Results : In order to select proper chemical for leaf spot disease control of P. sibiricum Redoute, Alternaria sp. was isolated from leave of P. sibiricum Redoute and pathogenicity was verified. Control value was checked after application on leaves for 3 times in 6-years-old field in Geumsan and 5-years-old field in Jaecheon. Chemicals were applied in June and July for 3 times totally without any other chemicals application. At 10 days after final chemical application, 20 plants were checked for infected leaf ratio on 20 leaves placed in middle and upper point of stem. In Geumsan, control value was higher as 88.3% in Pyraclostrobin, 86.1% in Polyoxin B, 84.4% in Pyribencarb, 82.2% in Iminoctadine tris (albesilate). In Jaecheon, control value was higher as 88.1% in Pyraclostrobin, 87.1% in Pyraclostrobin, 86.3% in Pyribencarb, 83.0% in Iminoctadine tris (albesilate). Conclusion : The result of this study on chemical selection for leaf spot disease control of P. sibiricum Redoute was as follows. Pyraclostrobin, Polyoxin B, Pyribencarb, and Iminoctadine tris (albesilate) showed excellent control value with over 80% and no damages. Above chemicals were considered excellent as chemicals for leaf spot disease in P. sibiricum Redoute.

Pectobacterium carotovorum subsp. carotovorum was found to be highly virulent to various vegetables, including Chinese cabbage. The antibacterial isolate CAB12243-2 was tested in a field bioassay for suppressing soft rot disease. The nucleotide sequencing of the 16S rRNA gene identified, the CAB12243-2 strain used in this study as Bacillus toyonensis. B. toyonensis CAB12243-2 inhibited the pectate lyase process by soft rot pathogens, and used trehalose and glucose as carbon sources. In field tests, the antibacterial isolate B. toyonensis CAB12243-2 suppressed soft rot disease with 73.0% control efficacy on the spring cultivar “Norangbom” and with 68.9% efficacy on the fall cultivar “Bulam 3”. These results suggest that B. toyonensis CAB12243-2 can be used as a biological control agent for the control of soft rot diseases on vegetables.

본 시험은 논으로부터 밭으로 윤환한 2년차인 답전윤환밭과 연속밭에 풋옥수수 찰옥4호 등 8품종을 사용하여 윤환밭과 연속밭의 병충해 발생, 생육 및 수량특성 차이 구명은 물론 풋옥수수의 체계적인 유기농 답전윤환 재배기술을 위한 기초자료를 확립하고자 수행한 결 과는 다음과 같다. 유기농 답전윤환 시 주요 병해는 전반적으로 연속밭에 비해 윤환밭에서 발병률이 높았으며, 시험품종 중 저항성 품종으로 발병률이 2% 미만인 흑진주찰과 대학찰 로 판단되었다. 유기농 답전윤환 시 주요 충해인 조명나방 유충 피해는 전반적으로 연속밭 에 비해 윤환밭에서 피해주율이 높았으며, 시험품종 중 저항성 품종으로는 피해주율이 낮 은 찰옥4호와 흑점2호로 판단되었다. 유기농 답전윤환 시 수량은 윤환밭에서 연속밭의 85 % 수준으로 감소하였으며, 답전윤환밭에서는 찰옥4호가 789.0 kg/10a로 가장 수량이 많았 다. 내병성, 내충성, 수량을 종합 평가하면 유기농 답전윤환 시 적합 품종으로는 찰옥4호, 흑진주찰, 흑점2호로 판단된다.

Background : In the year 2015, the area under rhizome of Rehmannia glutinosa in Chungnam province increased to 65% (105 ha) of domestic total cutivation area and is recognized as income crop. Since proper strorage method of rhizome has not been established, rhizome decay rate is so high during storage. This experiment was carried out to establish proper strorage method for stable production of rhizome of Rehmannia glutinosa Methods and Results : Korea jiwhang was used for this experiment and rhizome was cured under vinyl house and room temperature for 1, 2, 3 days respectively. Rhizome was stored for 140 days at –2 - 0℃ after curing, and rhizome quality and saprogen were investigated after storage. Trimming loss was 11.3 - 21.9%, higher in longer curig time and rice hull packing. Moisture content was 70.0 - 75.1%, higher in shorter curing time and no rice hull packing. Curing efficacy was better in vinyl house than room temperature, decay rate by weight and number of rhizome was lowest in 48hrs curing and no hull packing as 0.5% and 2.0% respectively. Identified saprogen during storage was Fusarium oxysporum, Fusarium tricinctum, Penicillium verrucosum, Mucor racemosus. Conclusion : Curing efficacy was better in 48hrs treatment under vinyl house with lowest decay rate and rice hull packing increased decay rate considerd due to saprogen existing in rice hull. 4 saprogens including Fusarium oxysporum were identified during storage of rhizome.

국내에서 수집된 모시풀 유전자원은 도입육성품종 11계통, 전남재래종 18계통, 전북재래종 7계통, 충남재래 종 10계통, 경남재래종 2계통, 경북재래종 1계통 등 49계통으로 주요 특성은 경장 121±11.4cm, 경직경 9.1±0.97mm, 유효경비율 36±12.6%, 생경중 1,814±376.9kg, 건섬유수량 35±21.8kg, 섬유비율 1.9±0.99%를 나타 내었고, 대체적으로 재래종에 비해 도입육성품종들의 생육 및 건섬유수량이 우수하였다. 주요 형질 중 섬유비 율과 건섬유수량의 변이가 크게 나타났다. 각 형질간 상관분석 결과 건섬유 수량과 경장, 경직경, 유효경비율, 섬유비율은 고도의 정의 상관관계를 나타내었다. 주성분 분석결과 2개의 주성분으로 49개 수집종에 대한 6개 형질을 설명할 수 있었는데 제1, 2주성분 값으로 군집분석을 한 결과 평균거리 0.8에서 4개 군으로 분류 되었다. 제 1군은 경장, 경직경, 섬유수량 등 생육이 우수한 수집종었고, 2군은 생육은 좋으나 섬유비율이 낮은 수집종이, 3군은 1군과 대조적으로 생육이 낮은 수집종이 분포하였으며, 나머지는 4군에 분포하였다. 12 URP primer를 이용하여 핵산지문분석에 의한 유연관계 분석 결과 왜모시풀과 비교해서 유사도는 0.437～ 0.928로 나타났으며, 유사도 0.57에서 6개 그룹으로 분류되었다. 1～4그룹은 다른 수집종과 독립성을 보였으 며, 5그룹은 대부분 전남지역에서 수집되었고 2개의 소그룹으로 분류할 수 있었는데 5-1은 해안지대로 2군의 생육이 낮은 수집종이 주로 분포하였고 5-2는 내륙지역으로 1군의 생육이 우수한 수집종이 분포하였다. 6그룹 은 3개의 소그룹으로 분류되었는데 전남, 전북, 충남, 경북의 다양한 지역이 혼재 되어있었다. 중국이나 일본 에서 도입된 육성품종은 유전적으로 매우 유사하였으며 국내재래종과도 유연관계가 가까운 군에 속했다.

A sequential planting method was developed to identify durable blast resistance in Korean rice cultivars. Two types of rice cultivars were investigated by a sequential planting after inoculation of mixed 26 rice blast isolates. Daesanbyeo and Gihobyeo, sh