• 한국식물병리학회지
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• 제1권1호
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• pp.17-21
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• 1985

비병원성 Pseudomonas solanacearum을 이용한 담배세균성마름병의 방제가능성이 검토되었다. Nutrient 액체배지 및 토양에서 비병원성균주는 병원성균주보다 생육속도가 빨랐으나 두 균주를 혼합하여 배양할 때 병원성균주에 대한 생육억제효과는 크지 않았다. 비병원성균주의 현탁액에 감수성 담배품종인 BY4의 뿌리를 6시간동안 침지시킨 후 병원성균주에 오염된 토양으로 이식한 결과, 높은 세균성마름병 방제효과를 얻었다. 비병원성균주의 현탁액을 가식상태의 담배에 토양관주하고 24시간 후에 포장으로 이식한 결과 7월 상순까지는 $30\%$이상의 세균성마름병방제효과가 인정되었으나 그 후 방제효과가 급속히 감소되었다.

• 생약학회지
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• 제41권4호
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• pp.255-263
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• 2010

Kojongsi persimmon (Diospyros kaki) is the major cultivar of astringent persimmon in southern of Korea. Kojongsi persimmon leaf has been traditionally used for acute and chronic diseases in Oriental countries. The purpose of this study was undertaken to investigate the antioxidative activities of the extract of Kojongsi persimmon leaf during growth. We investigated the antioxidant effects of the persimmon leaf extracts during growth on total polyphenol, total flavonoid, electronic donating ability (DPPH), nitrite (NO) scavenging and superoxide dismutase (SOD)-like activity. The next, we investigated the possible cell protective effects of the persimmon extract treatment against ultraviolet B (UVB)-induced injury in HaCaT keratinocytes. The contents of total polyphenol and flavonoid in leaf extract of Kojongsi persimmon were increased in time-dependent manner. In Jun, DPPH and NO radical scavenging and SOD-like activities in the leaf extract of Kojongsi persimmon was increased to the highest. However, the antioxidant activities in persimmon varieties were not any difference. The cell cytotoxicity by UVB irradation in HaCaT keratinocytes was significantly increased with the compared to the control group. However, the treatment of leaf extract of Kojongsi persimmon in HaCaT keratinocytes was shown to protective effect against UVB-induced cell cytotoxicity. These results suggest that the leaf extract of Kojongsi persimmon has potent antioxidant activity, and protective effect against UVB-induced keratinocyte injury. Thus, these properties may be contributed in the care of acute and chronic diseases.

• 한국농림기상학회지
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• 제4권2호
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• pp.114-118
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• 2002

충주지역에서 표고가 다른 9개 지점(계명산 5지점, 남산 4지점)에서 측정한 기온 관측자료를 분석하여 기온이 표고가 높아짐에 따라 일정한 비율로 변화하는 단열조건에 의한 기온체감율을 계산하고, 표고별 후지 품종의 만개기를 추정하였다. 충주 계명산 남서사면에서 측정한 시간별 기온자료를 표고와의 관계로부터 표고가 100 m 상승함에 따라 기온은 0.89$^{\circ}C$의 일정한 비율로 체감하였다. 남산 북서사면에서 측정한 시간별 기온자료와 표고와의 상관으로부터는 0.74$^{\circ}C$/100 m의 비율로 기온이 체감함을 알 수 있었다. 충주지역에서 일평균 기온 5$^{\circ}C$ 이상인 날의 발육속도(DVR)를 계산하여 추정한 만개기와 실제로 조사된 만개기는 서로 일치하는 경향이었으며 표고별로 추정된 충주지역의 사과 만개기는 해발고도 100 m 상승함에 따라 4~5일 늦어졌는데 고도에 따라 4월 25~5월 10일의 범위이었다.

• 한국환경과학회지
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• 제27권8호
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• pp.631-639
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• 2018

A Cultivation method to minimize the damage caused by high temperatures was studied by investigating the effects of groundwater cooling treatment on the growth, yield, and quality of strawberries. In the groundwater cooling treatment, the daily average temperature of the rhizosphere was reduced from $26.9^{\circ}C$ to $24.9^{\circ}C$. The root length increased by 0.3-9.2 cm, depending on the cultivar and growth period. The leaf number, leaf area, leaf length, leaf diameter, and plant height also increased, especially in the cultivars 'Seolhyang' and 'Maehyang', resulting in higher fresh and dry weights. The number of fruit per plant increased from 7.7 to 12.5 in 'Seolhyang', and the fruit weight increased by 0.3 g in 'Seolhyang' and 1.3 g in 'Maehyang'. The fruit hardness increased, but no significant difference in fruit coloration was observed. The sugar content of the fruit was improved by $0.2-0.3^{\circ}Brix$. Therefore, groundwater cooling of the rhizosphere was effective in improving the growth and productivity of strawberries under abnormally high temperature conditions and can be considered a cost-efficient cooling system.

• 한국작물학회지
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• 제44권3호
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• pp.282-287
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• 1999

The object of this study was to determine the difference of the time course changes of transpiration, diffusion resistance and photosynthetic rate of rice at several different growth stages subjected to soil moisture stress (SMS) and recovery by irrigation. A japonica rice cultivar 'Dongjinbyeo', was grown under flooded condition in a plastic container filled with silty loam soil. At 5 main growth stages, the container was treated by SMS until initial wilting point (IWP) and then reirrigated. The duration of SMS until IWP were the longest, 13 days for tillering stage, and the shortest, 7 days for panicle initiation and meiosis stage. The transpiration rate rapidly decreased during SMS and the transpiration rate at IWP of the stressed plant showed 10∼20% compared with control, and the transpiration rate of stressed plant at most growth stages also recovered rapidly after irrigation and then reached 100% of control within a week. The shoot photosynthetic rate in all growth stages rapidly decreased by SMS, and the rates at IWP of stressed plants were de-creased nearly to 0%, beside the treatment at tillering stage. The recovery degree of photosynthetic rate by irrigation ranged from 20 to 90%, showed higher at early growth stages of SMS treatment than that of later stages. At all growth stages the leaf diffusion resistance of stressed plants was over 3 times that of the control resulting from a rapid increase at 3 to 5 days after draining for SMS, and showed quick recovery by irrigation within 3 days after drainage. The above physiological parameters changed in close relation with the decrease of the soil matric potential after SMS. These results indicate that at all main growth stages of rice plants the transpiration and photosynthesis reduction by stomatal closure reponded sensitively to the first stage of SMS closely related with decrease of soil water potential, while those recovery pattern and recovered degree by irrigation are little different by growth stage of rice.

• 한국잡초학회지
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• 제16권2호
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• pp.132-139
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• 1996

제초제 cinosulfuron에 대해서 감수성이 각각 다른 두 품종을 선발해서 반응차이의 원인을 비교 검정하였다. 벼 어린식물체의 반응시험에서는 Indica type인 IR 74가 Japonica type인 화진벼보다 cinosulfuron에 대해서 높은 저항성을 보였다. 두 품종에서 추출한 ALS 효소의 활성은 cinosulfuron에 대해 비슥한 억제작용을 보였다. 10ppm cinosulfuron 처리에 대한 두 벼 품종간의 생육반응과 효소활성의 비교에서는 ALS효소 활성과 생육이 일치하는 경향을 보였다. IR 74의 효소활성과 생육은 시간이 지남에 따라 증가하는 경향이 있었으나, 화진벼에 있어서는 제초제 처리 후 5일째에 효소활성이 떨어졌으며 이시기에 유묘의 생육도 상당히 억제되었다. 두 벼 품종의 ALS효소는 cinosulfuron에 대해서 비슷한 감수성을 지닌 것으로 나타났으며 cinosulfuron을 처리한 유식물로부터 추출 가능한 효소의 양에서 차이가 나는 것으로 보아 다른 요인 즉 대사속도의 차이에 의해서 두 벼 품종의 생육반응이 다르게 나타난 것이 아닌가 사료된다.

• Plant Resources
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• 제6권1호
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• pp.16-26
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• 2003

Molecular markers are useful tools for evaluating genetic diversity and determining cultivar identity. Present study was conducted to evaluate the genetic diversity within a diverse collection of rice accessions used for Korean breeding programs. Two hundred eighty-seven rice cultivars, composed of temperate japonica, tropical japonica, indica, and Tongil-type of Korean crossing parents were evaluated by means of 15 simple sequence repeat (SSR) markers. A total of 99 alleles were detected, and the number of alleles per marker ranged from 4 to 11, with an average of 6.6 per locus. Polymorphism information content (PIC) for each of the SSR markers ranged from 0.2924 to 0.8102 with an average of 0.5785. These results, with the result that use of only 15 SSR markers made all rice cultivars examined could be uniquely distinguished, imply the efficiency of SSR markers for analysis of genetic diversity in rice. Cluster analysis was performed on similar coefficient matrics calculated from SSR markers to generate a dendogram in which two major groups corresponding to japonica (Group I) and indica and Tongil type rice (group II) with additional subclasses within both major groups. The narrowness of the Korean breeding germplasm was revealed by the fact that most of the Korean-bred and Japan-bred temperate japonica cultivars were concentrated into only 2 of the sub-group I-1 (143 cultivars) and I-2 (58 cultivars) among six sub-groups in major group of japonica. This is because of the japonica accessions used in this study was a very closely related ones because of frequent sharing of the crossing parents with similar genetic background with synergy effect of the inherited genetic difference between indica and japonica. A rice breeding strategy with the use of molecular markers was discussed for overcoming of genetic vulnerability owing to this genetic narrowness.

• 농업과학연구
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• 제25권1호
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• pp.12-18
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• 1998

숙기가 다른 세 가지 사과품종을 대상으로 각 품종간의 생리적 차이점 및 에틸렌발생 특성에 따른 저장전후의 과실 품질을 비교 조사하고 몇 가지 수확후 처리가 저장전, 후의 과실품질에 미치는 영향을 조사하였다. 과실의 성숙에 미치는 에틸렌의 작용수준이 품종에 따라 다르며 성숙시의 에틸렌발생량과 저장성과의 상관관계가 확인되지 않았다. 기능성필름의 경우 일반 PE보다 저장기간중 축적된 에틸렌양이 낮았고 에틸렌제거제의 처리로 다소간 경도가 높게 유지되었다. 과실의 외관품질은 에틸렌제거제처리 및 wax 처리로 크게 개선되었는데 특히 저장후 납질이 분비되어 상품성이 크게 나빠지는 '조나골드'의 경우 wax의 사용이 매우 효과적인 것으로 확인되었다.

• 농업과학연구
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• 제42권3호
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• pp.151-158
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• 2015

This study was conducted to know the variation and relationship of rice grain quality and starch pasting properties by transplanting times. Two early maturing rice cultivars which accounted for the most area of early maturing rice cultivar in Chungnam province were used. The experiment was laid out in a split-plot design with 3 replications. The main plot consisted of three transplanting times viz. early (April 25), ordinary (May 25) and late (June 25) with sub-plots containing two cultivars. According to the transplanting times, most of rice grain quality and starch pasting properties showed significant difference and Joami showed higher grain quality than Unkwang in all transplanting times. Especially, rice grain quality was improved when transplanted late, showing high head rice and glossiness of cooked rice due to the lower mean temperature during grain filling stage. Glossiness of cooked rice was positively correlated with head rice ratio, amylose content and setback value, and negatively correlated with chalky rice ratio and protein content. The highest positive and negative correlation were observed between breakdown value and peak viscosity ($r=0.98^{**}$), and breakdown and setback ($r=-0.94^{**}$), respectively. These results provide some information for rice researchers and producers producing cultivars with an improved quality, suggesting that rice quality is highly influenced by temperature at grain filling stage, and transplanting times is crucial in improving rice quality. In addition, starch pasting properties are useful for determining rice quality because rice grain quality and starch pasting properties are dependent on each other.

• Preventive Nutrition and Food Science
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• 제12권2호
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• pp.103-110
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• 2007

The protein profiles among Korean rice cultivars were assessed by total protein determination, solubility fractionation, SDS-PAGE analysis and scanning densitometry. In the extraction of protein, the SDS/urea system at a neutral pH was more efficient than that at alkaline pH. The determination of total protein showed that the protein content was similar among cultivars, ranging from 87.9 to 92.7 mg/g dry weight. Additionally, the water/NaCl-soluble protein fraction, containing 14${\sim}$16 kDa albumin and 22 kDa globulin ${\alpha}$-globulin, was also similar among cultivars, with a range of 9.94 to 11.98 mg/g dry weight. The SDS-PAGE/densitometry of total protein showed that there was no discernable difference in proteins of higher molecular weights among various cultivars, whereas the amount of lower molecular weight proteins (14${\sim}$16 kDa) is somewhat variable among cultivars. Furthermore, SDS-PAGE analysis of water/NaCl-soluble and propanol-soluble fractions indicates that there is a discernible change in the content of albumin, globulin or prolamin among cultivars. Thus, the PAGE/densitometry method, preceded by solubility fractionation, is useful for examining differences in protein profiles of rice cultivars.