• 한국조경학회지
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• 제23권3호
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• pp.106-112
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• 1995

This study was conducted to investigate the environmental factors of habitat of Lindera erythrocarpa and to test seedling growth of the plant transplanted in a field of Sung Kyun Kwan Univ. in Suwon, Kyungkido. The results were as follows ; 1. The wild lindera erythrocarpa was growing in Mt. Kwan whose January average temperature was -3.4$^{\circ}C$, and minimum average temperature was -14.8$^{\circ}C$ in January. It was also growing in Mt. Suri whose daily minimum temperature is 3.4$^{\circ}C$ lower than that of Seoul. Therefore, there was no problem for Lindera erythrocarpa to grow in Seoul regions in terms of winter coldness. 2. The growth of seedlings of Lindera erythrocarpa transplanted in a field of Sung Kyun Kwan Univ. in Suwon, Kyunkido in 1990 showed that average height of the tree was 1.64m, average diameter of root was 2.44cm, and that average width of crown was 1m. Therefore, there was no problem for Lindera erythrocarpa to grow under winter coldness in Suwon area.

• The Plant Pathology Journal
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• 제26권4호
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• pp.421-423
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• 2010

New sources of barley (Hordeum vulgare L.) resistant to spot blotch, caused by Cochliobolus sativus, are needed to provide effective resistance because of the rapid change pathotype patterns of C. sativus in fields. The purposes of our study were to develop a method to screen barley for resistance to spot blotch disease and then use this methodology to screen barley genotypes for resistance to the major virulent pathotype Pt4 in barley populations in Syria. A transparent tape method, in which a conidial suspension of C. sativus was dropped onto transparent tape and placed, treated-side down, on the second leaf surface of barley plants. Disease symptoms of fungus were easily detected on the leaves covered by the transparent tape after 48h of inoculation. The transparent tape method was repeatable and the disease scores obtained were correlated (r = 0.91, P = 0.001) with those obtained by the seedling assay. This method may be beneficial in various plant pathology breeding programs.

• The Plant Pathology Journal
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• 제24권1호
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• pp.63-66
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• 2008

The fermentation broth (FB) of Streptomyces griseofuscus 200401 isolated from non-farming soil showed antagonistic activity against powdery mildew fungus both in melon leaf/seedling assay and in field trials. The FB of S. griseofuscus 200401 was tested at different concentrations. In primary test, the control value of 2-fold diluted FB of S. griseofuscus 200401, compared to control, reached to 82.8%. The protective activity recorded 80.5% in 2-fold dilution of FB. The effect was reduced to 28.9% in high dilution (100-fold) treatment. The curative effect was relatively lower than protective activity. In field test, the antifungal activities of S. griseofuscus 200401 remained low in blocks sprayed with 100-fold diluted FB and the control values were 15.2 and 15.9% in 2005 and 2006, respectively. However, the activities were as high as 65% and 67.3% in the blocks treated with 2-fold dilution of FB during the same period.

• 한국작물학회지
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• 제51권4호
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• pp.356-361
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• 2006

The present study was conducted to determine plant growth and physiological responses of corn, barnyardgrass, and soybean to ALA (5-aminolevulinic acid). ALA effect on early seedling growth of test plants was greatly concentration dependant, suggesting that it inhibits at higher concentrations. No significant difference in herbicidal activity of two types of ALA on plant height and weight of test plants was observed. Barnyardgrass was the most sensitive to ALA and followed by corn and soybean, indicating that both crop plants were less affected by ALA concentration as well as different growth stages than barnyardgrass. Greatly reduced chlorophyll contents from leaves of three plant species were observed with increasing of ALA concentration. Compared with untreated controls, higher amounts of three tetrapyrroles were detected from three crop plants, indicating more accumulation in ALA-treated plants. The differential selectivity among plant species would be explained with the differences in tetrapyrrole accumulating capabilities, the susceptibility of various greening groups of plant species to the accumulation of various tetrapyrroles, and their metabolism in various plant tissues. The results indicate that negative biological potential of ALA exhibited differently on plant species, and that the photodynamic herbicidal activity against susceptible plants highly correlated with the extent of tetrapyrrole accumulation by the species.

• 한국환경복원기술학회지
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• 제8권5호
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• pp.47-55
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• 2005

This study was conducted to suggest revegetation character for environment factor of slope. Field test carried out for the man-made slope with three types(0.5cm no net, 3.0cm no net, 3.0cm net) revegetation methods in Hwaseong. Test revegetation plants were Festuca arundinacea, Lolium perenne, Lespedeza cyrtobotrya and Indigofera pseudo-tinctoria M. The result of this study can be summarized as follows; 1. The soil hardness, the soil acidity, and the soil humidity of three types(0.5cm no net, 3.0cm no net, 3.0cm net) revegetation methods were at a suitable value for plants growth. 2. All plant growth index(seedling number, ground coverage, plant height, plant weight, etc) of south slope were better than north slope. But plant growth index of net plots were similar to no net plots. 3. For washout investigation, washout quantity of north slope was plentifully measured from south slope, and 1 amount of rainfall will be big was visible appears plentifully.

• Journal of Biosystems Engineering
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• 제14권3호
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• pp.181-187
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• 1989

The mechanical and rheological properties of agricultural materials which influence the machine design or handling are not completely understood. Agricultural materials do not react in a purely elastic manner, and their responses when subjected to stress and strain appear a combination of elastic and viscous behavior. Many researchers have studied the mechanical and rheological properties of the various agricultural materials, but those properties are available mostly for foreign varieties of agricultural products. Rheological properties of rice seedlings become important to formulate the principles governing their mechanical behavior. The objectives of this study were to experimentally determine the creep and recovery behavior of rice seedlings of one japonica-type and one Indica x japonica hybrid in the transplanting age. The results of this study are summarized as follows; 1. The compression creep and recovery behavior of mat-type seedlings could be described by 4-element Burger's model. 2. The steady-state creep appeared at the stress larger than 0.8 MPa and the logarithmic creep appeared at the stress smaller than 0.8 MPa. 3. In the compression creep test of the rice seedlings, the instantaneous elastic modulus of Burger's model showed the range from 20 to 40 MPa. The higher value of absolute viscosity for the rice seedling explained that the rice seedlings were viscoelastic materials. 4. In the recovery test of the rice seedlings, there was a tendency that the higher permanent strain of all samples was observed under the smaller stress being appeared, and the larger permanent strain in Dongjin was observed than in Samkang.

• 한국작물학회지
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• 제49권5호
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• pp.373-380
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• 2004

The production of sweet (su) and super sweet corns (sh2) has been economically feasible in Korea in recent years. Major factors limiting super sweet corn production are low germination and low seedling vigor. Since seed quality is closely related to seed maturity, the optimum harvest time for the seed production of sweet and super sweet corns was studied and the quality of seeds with varying maturities was investigated in 2001 and 2002 cropping seasons. The parents of the sweet corn seeds were Hybrid Early Sunglow and 'Golden Cross Bantam 70' and those of super sweet corn were Xtrasweet 82 and 'For­tune'. Seeds were harvested at 21, 28, 35, 42, 49, and 56 days after silking (DAS). As the seeds developed, seed weight of sweet corn increased and the seed moisture content decreased faster than that of super sweet corn. Germination rates of sweet corn seeds harvested 21 and 28 DAS at $25^{\circ}C$ and emergence rates in the cold soil test were significantly lower than those of seeds harvested after 42 DAS in both years. Although the germination rates of super sweet corn seeds with varying maturities showed similar patterns as sweet corn seeds at $25^{\circ}C$, the emergence rate of super sweet corn seeds in cold soil test continuously increased with seed maturity. This suggests that seed quality of super sweet corn should be tested in a cold soil test to estimate field emergence. As the seeds developed, leakage of total sugars and electrolytes from the both sweet and super sweet corn seeds decreased up to 42 or 49 DAS. The $\alpha-amylase$ activities of both sweet and super sweet corn seeds increased with seed maturity from 21 to 35 or 49 DAS depending on genotype and year. The optimum harvest time for the seed production of sweet corn was 42 DAS and 49 DAS for super sweet corn considering emergence rate and plumule dry weight in the cold soil test, leakage of sugars and electrolytes from the seeds, and $\alpha-amylase$ activity.

• 한국작물학회지
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• 제41권3호
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• pp.348-353
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• 1996

1. 돌연변이처리후 실내에서 처리된 종자의 발아율, 제 1 엽 및 뿌리의 생장율을 보면 gamma ray나 화학제 처리된 Dema M$_1$, 유묘의 경우 생존율이 l~49%정도 감소하였고 Grosso의 경우는 그 감소의 폭이 Dema보다 적어 두 품종간의 돌연변이제에 대한반응의 차가 컸으며 같은 처리농도의 화학돌연변이제를 처리할 경우 두번에 나누어 중간의 휴지기를 두고 처리하는 것이 한 번에 처리하는 것보다 식물체의 생장 저해정도가 덜하였다. 2. 포장 M$_1$식물체의 간장의 감소율을 보면 화학약제의 경우 8.5~38.5%의 범위로 간장이 줄어들었으며 특히 1.5 mM의 MNH 처리시는 두 품종 모두 파종된 식물체가 고사하였고 0.75~l.0mM의 MNH처리시 15~38%심하였다. 그러나 이중처리할 때는 1.0~l.5mM이상의 고농도로 처리하여도 간장의 생장 감소율은 단일처리보다 상대적으로 덜 하였으며 이는 두 품종 모두 비슷한 경향이었다. 3. Dema에서는 gamma ray 180Gy처리시 간장의 감소가 28% 정도로 가장 심하였고 Grosso에서는 150Gy에서 13%로 가장 심한 경향이었다. 4. M$_2$식물체의 엽록소 돌연변이 발생율을 보면 화학약제나 방사선 처리 모두 처리강도가 높을수록 albino, xantha등의 엽록소 돌연변이체가 많이 나타났으며 약제의 이중 처리시 엽록소 돌연변이의 출현률이 다른 처리보다 높았다.

• 한국작물학회지
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• 제42권6호
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• pp.652-665
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• 1997

미국자리공 및 겨자무의 잎추출물을 이용하여 기내배지상에서 몇가지 작물들과의 allelopathy를 조사한 결과는 다음과 같다. 1. 미국자리공 잎의 methanol 추출물의 농도가 증가함에 따라 공시한 모든 작물의 발아율, 근장, 배축장, 초장, 생체중, 건물중, 유묘의 활력이 급격하게 감소하였다. 2. 미국자리공의 autoallelopathy는 고농도(50$\mu$l 및 100$\mu$l) 첨가시에 나타나기 시작하였으며, 생체중과 건물중은 농도가 증가함에 따라 현저히 감소하였다. 3. 겨자무 잎의 methanol 추출물은 공시한 모든 작물의 초기생장량을 유제시키는 효과는 보였으나, 미국자리공의 잎추출물의 효과보다는 높았다. 4. 겨자무 뿌리의 methanol 추출물 처리는 밀, 미국자리공의 배축장을 농도 증가에 따라 감소시켰으나, 나머지 작물은 증가시켰다. 또한 초장도 밀, 고추, 미국자리공에서는 추출물의 농도가 증가할수록 감소하였으나 그 외의 작물에서는 약간 증가하였다. 5. 미국자리공의 methanol 추출물로부터 재출물한 4종의 분획물 중 ethyl acetate 분획물이 발아율 및 초기생육을 가장 크게 감소시켰다. 6. Ethyl acetate 분획물은 다른 분획물보다 벼, 보리, 배추의 엽록소 함량을 감소시켰다. 7. Ethyl acetate 분획물 100$\mu l$l 첨가시에 배추의 유리 proline의 함량은 31.2배 증가하였으며, 추출물농도가 증가할수록 proline 함량이 증가하였다.

• 한국환경농학회지
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• 제6권1호
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• pp.44-49
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• 1987

본 연구는 제초제인 alachlor이 가지는 선택성이 식물고유의 생화학적 차이에 기인한다는 가정하에, 이의 규명을 목적으로 수행하였다. 공시작물인 대두, 배추 및 피는 alachlor 수용액의 처리로 경중의 약해를 입었으며 그 피해는 해당식물의 glutathione 또는 homoglutathione 함량이 많을 수록 적었다. 비효소적 반응조건 하에서 가한 alachlor의 17.7%가 GS-alachlor conjugate로 전환됨을 관찰하였으며, 이어 수행한 공시작물의 유묘시험에서는 처리한 C-14 표지 alachlor이 단시간(24hrs)에 4∼5개의 수용성 대사물로 전환되 었으며, 주요대사물로 대두에서는 homoglutathione-alachlor, 깨, 배추 그리고 피에서는 glutathione-alachlor conjugates를 잠정적으로 확인하였다. 본 연구에서 채택한 3종의 공시식물의 경우, 식물체 내에서 glutathione (및 homoglutathione)과 alachlor와의 phase Ⅱreaction인 conjugation 반응이 해독반응으로 작용, alachlor의 선택성에 공헌하는 것으로 해석하였다.