• 식물병연구
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• 제24권2호
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• pp.138-144
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• 2018

In December 2016, stem rot symptoms were observed on Persian buttercup (Ranunculus asiaticus) plants in Chilgok, Gyeongbuk, Korea. In the early stage of the disease, several black spots appeared on the stem of infected plants. As the disease progressed, the infected stem cleaved and wilted. The causal agent was isolated from a lesion and incubated on Reasoner's 2A (R2A) agar at $25^{\circ}C$. Total genomic DNA was extracted for phylogenetic analysis. Based on the 16S rRNA gene analysis, the isolated strain was found to belong to the genus Pseudomonas. To identify the isolated bacterial strain at the species level, the nucleotide sequences of the gyrase B (gyrB) and RNA polymerase D (rpoD) genes were obtained and compared with the sequences in the GenBank database. As the result, the causal agent of the stem rot disease was identified as Pseudomonas marginalis. To determine the pathogenicity of the isolated bacterial strain, it was inoculated into the stem of healthy R. asiaticus plant, the inoculated plant showed a lesion with the same characteristics as the naturally infected plant. Based on these results, this is the first report of bacterial stem rot on R. asiaticus caused by P. marginalis in Korea.

• The Plant Pathology Journal
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• 제16권3호
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• pp.156-161
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• 2000

A wilt disease occurred on greenhouse-grown eggplants at Yeojoo, Korea in 1997. The wilted eggplants had leaves with gradual yellowing, interveinal necrosis, and marginal crinkling. Vascular tissues of diseased stems were discolored, turned black, and microsclerotia developed at the base of stems. The disease progressed from lower parts of the plants upward. Fungal isolates from discolored vascular tissues were initially whitish to cream color on potato-dextrose agar (PDA) plate, which later turned black due to the formation of microsclerotia. Conidiophores were erect, hyaline, verticillately branched, and had 3 or 4 phialides arising at each node. Phialides were hyaline, arranged in whorls, and measured as 17.5-32.5 x 2-3$\mu\textrm{m}$. Conidia were hyaline, ellipsoidal to sub-cylindrical, mainly one-celled, and measured as 5-8.8 x 2-4$\mu\textrm{m}$. Conidia were borne in small clusters at the tips of phialides. Microsclerotia formed on PDA plates, and consisted of globular cells that formed irregular masses of various shapes. Chlamydospores were absent. Based on these cultural and morphological characteristics, the fungus was identified as Verticillium dahliae Klebahn. Pathogenicity tests by root cutting, root dipping or soil drenching resulted in similar symptoms observed in the naturally infected eggplants. This is the first report on occurrence of Verticillium wilt of eggplant in Korea.

• The Plant Pathology Journal
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• 제17권2호
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• pp.101-105
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• 2001

A disease survey on the carnation (Dianthus caryophyllus L.) wilt was conducted during the high temperature period (June through August) and the low temperature period (February through May) in 58 greenhouses of its major cultivation areas, including Pusan, Kimhae, and Changwon in Korea from 1998 to 1999. The disease incidence was averaged 5.4% and 11.9% in the low and high temperature periods, respectively. Severe damage was found in summer with high incidences of around 50% in some greenhouses. Close examination of the symptoms and isolation of the causal agent revealed that there was a new disease different from Fusarium wilt caused by Fusarium oxysporum f. sp. dianthi, which was determined as the stub dieback caused by F. was cetermined as the stub dieback caused by F. graminearum (teleomorph : Gibberella zeae). The stub dieback symptoms involved brown rot of stem that started usually from the portion of cutting without discoloration of inner vascular tissues. Seven out of 38 isolates from the wilted plants were identified as F. graminearum, while the others as F. oxysporum f. sp. dianthi. Mycological characteristics of the stub dieback pathogen including colony color, absence of microconidia, and the shape of macroconidia, were consistent with F. graminearum previously described. This is the first report of the carnation stub dieback in Korea.

• 식물병연구
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• 제29권3호
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• pp.304-309
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• 2023

Wilted and water-soaked lesion symptoms were observed on cucumbers in greenhouses located in Daejeon, Chungcheongnam-do, Korea, in June 2021. A bacterial strain, designated KNUB-04-21, was isolated from the cucumbers, which was subsequently identified as Pectobacterium brasiliense through a phylogenetic analysis based on sequences of the 16S rRNA region, dnaX, leuS, and recA genes. The biochemical characteristics of KNUB-04-21 were also similar to those of P. brasiliense through investigation using the API ID 32 GN system. The pathogenicity of KNUB-04-21 was confirmed by inoculating it into healthy cucumber plants. The reisolated strains were also found to be same to the original strain. To our knowledge, this is the first report of P. brasiliense being identified as the causative agent of cucumber soft rot in Korea.

• Animal Bioscience
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• 제37권7호
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• pp.1185-1195
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• 2024

Objective: This meta-analysis aimed to evaluate the impact of wilted and unwilted silage on various parameters, such as nutrient content, fermentation quality, bacterial populations, and digestibility. Methods: Thirty-six studies from Scopus were included in the database and analyzed using a random effects model in OpenMEE software. The studies were grouped into two categories: wilting silage (experiment group) and non-wilting silage (control group). Publication bias was assessed using a fail-safe number. Results: The results showed that wilting before ensiling significantly increased the levels of dry matter, water-soluble carbohydrates, neutral detergent fiber, and acid detergent fiber, compared to non-wilting silage (p<0.05). However, wilting significantly decreased dry matter losses, lactic acid, acetic acid, butyric acid, and ammonia levels (p<0.05). The pH, crude protein, and ash contents remained unaffected by the wilting process. Additionally, the meta-analysis revealed no significant differences in bacterial populations, including lactic acid bacteria, yeast, and aerobic bacteria, or in vitro dry matter digestibility between the two groups (p>0.05). Conclusion: Wilting before ensiling significantly improved silage quality by increasing dry matter and water-soluble carbohydrates, as well as reducing dry matter losses, butyric acid, and ammonia. Importantly, wilting did not have a significant impact on pH, crude protein, or in vitro dry matter digestibility.

• Asian-Australasian Journal of Animal Sciences
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• 제26권2호
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• pp.195-201
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• 2013

A lab-scale ensiling study was carried out to investigate the fermentation quality of water hyacinth (WH) supplemented with molasses, rice bran, as an absorbent, and an inoculant in the form of fermented vegetable juice and their combinations. After wilting the water hyacinths for 7 h to a dry matter (DM) content of 240 to 250 g/kg, the following treatments were applied: i) Control (C), WH only; ii) WH with sugarcane molasses at 40 g/kg WH (CM); iii) WH inoculated with fermented vegetable juice at 10 ml/kg WH (CI); iv) CM and CI (CMI) combined; v) WH with 150 g rice bran/kg WH (CA); vi) CA and CI combined (CAI); vii) CA and CM combined (CAM); and viii) CA, CM and CI combined (CAMI). After application of additives, the differently treated forages were mixed and ensiled in triplicates in 1,500-ml polyethylene jars. After ensiling for 3 d, pH values in all treatments, except C and CI, had decreased to approximately 4.0 and remained low till 14 d. After 56 d, pH had increased between 0.4 to 0.9 pH-units compared to those at 14 d. The ammonia nitrogen ($NH_3$-N) concentration ranged from an acceptable level in treatment CM (8 g/kg N) to a high $NH_3$-N value in treatment CMI (16 g/kg N). Lactic acid formation was higher in CI than in all other treatments. Butyric acid contents, which indicate badly fermented silages, were low in all silages (<2 g/kg DM). There were two-way interactions (p-values from <0.001 to 0.045) for almost all fermentation end-products and pH, except for the molasses${\times}$inoculant interaction on $NH_3$-N (p = 0.26). Significant 3-way interactions were found on all observed variables except for weight losses of silages. It is concluded that conserving wilted WH as silage for ruminants may be improved by the addition of molasses or rice bran.

• 한국식품영양학회지
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• 제21권1호
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• pp.28-34
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• 2008

This study was performed in an effort to standardize the quality of fresh-cut products. Here, consumers' perceptions of fresh-cut products were surveyed to determine the quality factors in preparing quality standards for fresh-cut products. According to the surveys, freshness was the most important factor for consumers when choosing fresh-cut products at the market. Secondary indicators of good quality, i.e., "sensory qualities," were determined to be vibrant color, clean taste, nice feel, neat presentation, etc., as well as knowledge of whether it was organically grown. Off-odors decreased a product's marketability. Likewise, the more wilted or brown it appeared, the less a product was desired. From the results, the quality control indices for fresh-cut products were derived as freshness, discoloration, off-flavor, uniformity, prohibition of adulteration by alien substances, packaging and labeling. The quality of fresh-cut lettuce samples was measured against three storage temperatures: $20^{\circ}C,\;10^{\circ}C$ and $5^{\circ}C$. Sensory quality evaluations revealed the following: produce stored at $20^{\circ}C$ lost its marketability in less than one day; produce stored at $10^{\circ}C$ lost its marketability in less than two days; on the other hand, produced stored at $5^{\circ}C$, maintained its marketability for six days. At these respective points, browning started to occur around cut areas, and increased gradually once it began. Vitamin C content decreased with storage time, but storage at $5^{\circ}C$ maintained vitamin content the longest duration. Finally, further examinations were performed on the sensory qualities of fresh-cut lettuce samples at four levels of increased browning. Up to the third level, the product score for marketability was 5.6.

• 한국토양비료학회지
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• 제16권2호
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• pp.179-182
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• 1983

비닐하우스내(內) 풋고추 재배단지에서 카바이트 부산소석회 시용(施用)에 의(依)한 피해실태조사와 그 원인(原因)을 구명(究明)하기 위하여 재현시험을 실시한 결과(結果) 1. 카바이트 부산소석회 시용구에서는 정식후(定植後) 새 뿌리 발생이 전연 안되었으며 엽면(葉面)에는 많은 암갈색(暗褐色) 얼룩점이 산재(散在)하였고 위조낙엽(萎凋落葉)되면서 뿌리 내림이 불량(不良)하였다. 2. 카바이트 부산소석회 시용구의 식물체는 소석회 시용구의 식물체보다 호흡량(呼吸量)이 떨어졌다. 3. 카바이트 부산소석회에는 아세틸렌가스($C_2H_2$) 발생이 많았고 이 석회를 시용(施用)한 피해(被害) 토양에서도 가스가 발생되었으며 발생량이 많을수록 고추의 피해(被害)가 심(甚)하였다.

• 식물병연구
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• 제17권3호
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• pp.399-401
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• 2011

경남 산청군 신등면 농가포장에 재배중인 초석잠에서 Sclerotium rolfsii에 의한 흰비단병이 발생되었다. 병징은 줄기와 잎이 수침상으로 물러지고 썩으면서 서서히 시들어 말라 죽었다. 병반부와 지제부의 토양 표면에 흰색의 곰팡이가 발생하고 갈색의 작은 둥근 균핵을 많이 형성하였다. 균핵의 크기는 1-3 mm이며 균사의 폭은 4-9 ${\mu}m$였다. 균사특유의 clamp connection이 관찰되었다. 균사생육과 균핵형성 적온은 $30^{\circ}C$이었다. 이와 같이 초석잠에서 발생한 병징과 병원균의 균학적 특징을 근거로 하여 이 병을 S. rolfsii Saccardo에 의한 초석잠 흰비단병으로 명명하고자 제안한다.

• 생물환경조절학회지
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• 제8권1호
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• pp.36-41
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• 1999

본 연구는 토양근권제한이 멜론의 수량과 품질에 미치는 영향을 구명하고자, 격리상, 간이근권제한시트 및 관행 토양재배의 3가지 재배방법을 적용하여 멜론을 4월19일 부터 7월 17일까지 재배하였다. 지온은 격리상재배가 토양재배와 근권제한시트 재배보다 다소 높게 유지되었고 멜론의 생육은 토양과 근권제한시트재배에 비해 격리상 재배에서 빨랐다. 과실크기는 토양, 격리상 및 근권제한시트재배 순이었으나 당도 및 네트형성은 격리상재배가 토양재배에 비해 우수하였다. 수확기 경엽의 시들음주율은 토양재배 26.7%, 근권제한시트재배 25% 발생한 데 비해 격리상재배는 3.3%로 가장 낮았다 따라서 상품과 수량은토양재배에 비해 격리상재배에서 많았다.