• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.40-40
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• 2017

Rice (Oryza sativa L.) is one of major crops of Vietnam. Rice plant contains many secondary metabolites that are potent to inhibit growth of other plants. This study was carried out to find potential plant growth inhibitors from rice plants. Seven rice varieties were cultivated in the fields affiliated to Hiroshima University, Japan; Mature stems and leaves from each variety were collected, and then they were extracted with methanol, hexane, ethyl acetate, butanol, and water. Total phenolic content and total flavonoid content were the highest in ethyl acetate extract. DPPH antioxidant assay results showed that the ethyl acetate extract also had higher $IC_{50}$ value. Therefore, the ethyl acetate extracts were selected for laboratory bioassay. Results showed that the two-local variety Re nuoc and Nan chon inhibited the germination of radish and barnyard grass seedlings at the greatest levels, as compared to other cultivars. HPLC quantification indicated that the ethyl acetate extracts of Re nuoc and Nan chon rice plant parts consists of phenolic and flavonoids compounds which are potent as plant growth inhibitors. Further laboratory bioassay and field experimentation will be conducted to validate the laboratory bioassay findings.

• 한국작물학회지
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• 제46권4호
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• pp.317-320
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• 2001

Sweet com seeds deteriorate faster due to low starch content than field com seeds when stored for a long tenn. This study had been conducted to observe the seed deterioration of four different sweet corns in a long tenn storage conditions in room temperature. Four kinds of sweet com genes (sh2, bt, su, and se) were harvested from 15 days to 50 days after silking with 5-day intervals. These seeds were stored in the room temperature and tested for germination percentages from 3 months to 18 months period with 3-month interval. su seeds germinated better than other types of gene. Hybrid Mecca which is sh2 gene germinated better when stored for 3 months to 18 months. For all genes, mean regression equations in relation to storage periods showed linear responses. For regression equation, the slope of sh2 gene was lower than that of su gene. The highest slope value was observed in bt gene showing faster deterioration rate. The rate at which seed deteriorates seems to be affected by the date at which it was harvested. The seeds that were harvested at the optimum time deteriorated more slowly than those which were not.

• Journal of Ecology and Environment
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• 제29권1호
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• pp.17-22
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• 2006

Since the demands not only for value-added timber but the environmental functions of forests had been increased, native tree species has been, and is rapidly being replaced by foreign tree species in many parts of the world. However, the studies on population structure and regeneration characteristics of native tree species were not conducted enough. Regeneration of Kalopanax septemlobus growing among other hardwoods in natural forests is very difficult because of its low seed viability and germination rate. The study examined the distribution of mature trees of K. septemlobus and their regeneration pattern at the 1.12 ha study plot in natural deciduous broad-leaved forest of Mt. Jeombong. The density and mean DBH of K. septemlobus was 97 trees per ha and 32 cm, respectively. The spatial distribution of K. septemlobus showed a random pattern (aggregation index is 0.935) in the 1.12 ha study plot. The age of 90 trees among 99 sample trees of K. septemlobus ranged from 90 to 110 years and represented a single cohort, thus suggesting that K. septemlobus in advance regeneration has regenerated as a result of disturbances such as canopy opening.

• Geomechanics and Engineering
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• 제17권4호
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• pp.323-331
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• 2019

The presence of defects in nature changes the physical parameters of the rock. In this paper, by studying the rock-like specimens with conjugated fractures, the horizontal angle and length are changed, and the physical parameters and failure modes of the specimens under uniaxial compression test are analyzed and compared with the results of simulation analysis. The experimental results show that the peak strength and failure mode of the rock-like specimens are closely related to the horizontal angle. When the horizontal angle is $45^{\circ}$, the maximum value is reached and the tensile failure mode is obtained. The fracture length affects the germination and propagation path of the cracks. It is of great significance to study the failure modes and mechanical properties of conjugated fracture rock-like specimens to guide the support of fractured rock on site.

• The Plant Pathology Journal
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• 제40권5호
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• pp.475-485
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• 2024

Chili pepper anthracnose, caused by Colletotrichum spp., is a significant biotic stress affecting chili fruits globally. While fungicide application is commonly used for disease management due to its efficiency and cost-effectiveness, excessive use poses risks to human health and the environment. Botanical fungicides offer advantages such as rapid degradation and low toxicity to mammals, making them increasingly popular for sustainable plant disease control. This study investigated the antifungal properties of Cestrum tomentosum L.f. crude extracts (CTCE) against Colletotrichum scovillei. The results demonstrated that CTCE effectively inhibited conidia germination and germ tube elongation at 40 ㎍/ml concentrations. Moreover, CTCE exhibited strong antifungal activity against C. scovillei mycelial growth, with an EC50 value of 18.81 ㎍/ml. In vivo experiments confirmed the protective and curative effects of CTCE on chili pepper fruits infected with C. scovillei. XTT analysis showed that the CTCE could significantly inhibit the cell viability of C. scovillei. Mechanistic studies revealed that CTCE disrupted the plasma membrane integrity of C. scovillei and induced the accumulation of reactive oxygen species in hyphal cells. These findings highlight CTCE as a promising eco-friendly botanical fungicide for managing C. scovillei infections in chili peppers.

• 식물병연구
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• 제9권2호
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• pp.72-78
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• 2003

프로라츠, 터부코나졸, 베노밀, 만코지, 지오판, 아족시스트로빈, 후루아지남 등 8종의 농약이 Fusarium oxysporum 에 의한 춘란(Cymbidium goeringgii) 구경썩음병 방제효과를 검토하였다. 이들 중 프로라츠와 터부코나졸이 병원균의 성장억제효과와 병 방제효과가 가장 우수하였다. 이들 농약은 유효성분 10ppm에서 병원균의 균사 생장 95~100% 억제하였으며, 100ppm 에서 포자발아율을 75~100% 억제하였다. 한국춘란(무명소심)과 중국춘란(녹운)에 대한 프로라츠와 터부코나졸의 구경썩음병 방제효과는 거의 없거나 50% 이하로 낮았으며 발병 후 치료효과는 0~20%이하로 매우 낮았다. 본 연구의 결과로 볼 때 프로라츠와 터부코나졸을 병 발생 전에 예방적으로 적용하면 춘란구경썩음병을 효과적으로 방제할 수 있는 것으로 판단된다.

• The Plant Pathology Journal
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• 제18권1호
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• pp.36-42
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• 2002

Resistance of perilla varieties to Botrytis cinerea LVF12 was evaluated, while antagonistic bacteria were selected and tested for their efficacy towards biological control of gray mold rot caused by B. cinerea. Among 11 perilla varieties tested for disease resistance, Milyang variety showed some degree of resistance, while the rest of varieties showed no resistance. Among 250 bacterial isolates collected from perilla loaves and rhizosphere of perilla plants, six isolates showed high levels of inhibitory effect on mycelial growth and conidial germination of B. cinerea in in vitro test. Using the pot test in growth chambers these isolates showed high levels of disease suppression, with Nl isolate showing 95.3% of control value and N4 isolate showing 90.8% of control value. Further test was performed to evaluate the two isolates ability for disease prevention and/or disease therapy, and results showed almost 100% of control vague. Isolates Nl and N4 were identified as Bacillus licheniformis and 5. megatepium, respectively, according to Bergey's manual, API 20E and 50CHB test kit, and Transmission electron microscope.

• 한국작물학회지
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• 제45권4호
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• pp.261-266
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• 2000

This study was to investigate antioxidative activity of rice grain using 1, 1-Diphenyl-2-picrylhydrazyl(DPPH) and thiobarbituric acid (TBA) method and germination ability for screening rice varieties with high antioxidative activities on korean native and foreign rice varieties harvested in 1998 and 1999. The average antioxidative activity of foreign rice varieties (DPPH 63.5% and TBA 55.2%) was significantly higher than that of native rice varieties (DPPH 47.2% and TBA 45.6%) on varieties harvested in 1999. The promptness index (PI) of native rice varieties was higher in stored rices for three months (mean PI=160.7) than that of stored rices for a year (mean PI=141.6). On the other hand, the PI of foreign rice varieties was higher in stored rices stored for a year (mean PI=176.7) than that of stored rices for three months (mean PI=157.5). Varieties with high redness of hulled rice (a-value) showed significant lipid peroxidation inhibitory activity to DPPH in a stored rices for a year (r=${0.5744}^**$) and stored rices for three months (r=${0.5630}^**$) . These results indicate that the pigments of hulled rice varieties may play important antioxidative roles and colored rice varieties with higher antioxidative potentials can be developed and also may provide information with rice breeder to breed rice variety with a high antioxidative activity for a rapid screening of a small amounts of a large number of samples using color value.

• Applied Biological Chemistry
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• 제24권1호
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• pp.67-73
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• 1981

보리와 발아보리의 생체내 영양효율을 알기위해 동물실험을 행하였다. 젖뗀 albino rat를 사용하여 단백질원으로 보리 및 발아보리만을 사용한 군, 단백질(5%의 casein)을 첨가해준, 그리고 쌀(쌀:보리=8:2) 및 단백질(5% casein)을 혼합 첨가시킨군으로 나누어 4주간 사육하여 다음과 같은 결과를 얻었다. 1. 식이 및 열량섭취량, 식이의 효율 및 체중은 보리 및 발아보리에 단백질을 첨가시킨군들에서 높았으며 쌀과 단백질을 첨가시킨군들에서는 현저히 높아 통계적으로 유의성을 보였다. 그러나 보리군들과 발아 보리군들간의 차이는 볼 수 없었다. 2. 단백질의 효율은 단일 곡류군들과 단백질 첨가군들에 비해 쌀과 단백질 혼합첨가군들이 높음을 보여 흔합된 곡류단백질이 체내효율을 높이는 것으로 나타났다. 3. 식이 및 단백질의 소화흡수율을 보면, 단일곡류군들에서는 표준군에 비해 보리군 및 발아보리군들이 낮음을 보였다. 그러나 여기에 단백질 또는 쌀과 단백질을 혼합 첨가하였을 경우 보리군들에 비해 발아보리군들의 단백질 소화흡수율이 현저히 증가하였다. 따라서 발아보리의 영양효과는 발아보리와 함께 동물성단백질을 적당히 섭취할 경우 단백질의 소화흡수율을 크게 증가 시키는데 있다고 할 수 있다.

• 한국건설순환자원학회논문집
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• 제9권2호
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• pp.117-126
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• 2021

이 연구에서는 사면과의 부착력과 식물 생장력이 높은 식생기반재를 개발하고자, 시멘트 기반의 결합재와 기능성 첨가제를 혼합한 녹생토의 기초물성과 식물 생장에 미치는 영향을 평가하였다. 석고계 시멘트를 혼합한 녹생토(No.3)의 전단강도가 낮게 나타났으나, 식생 환경에 가장 적합한 경도 수준(23.6mm) 및 pH 값(7.4)을 나타냈다. 또한, 보습제를 첨가하여 성능을 개선한 녹생토의 초기 식생 발현은 일반 녹생토 비해 늦고 전도도값은 다소 높은 경향을 나타냈다. 반면, 성능을 개선한 녹생토는 타설면과의 부착력이 높았으며, 일정 시간 경과 후의 식물 생장 속도 및 동절기와 환절기 재생능력이 우월한 것으로 나타났다.