• 한국자원식물학회지
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• 제31권5호
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• pp.522-530
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• 2018

Brachypodium distachyon has been developed as a monocot model plant for temperate grasses and bioenergy crops. Although B. distachyon research is moving forward rapidly, the study of photoresponses has not been explored. To extend our knowledge of responses to light in monocots, we performed photoresponse analysis of B. distachyon using two inbred lines, Bd21 and Bd21-3. In this study, we first compared growing phenotypes between the two lines and investigated coleoptile and primary leaf growths under dark, far-red, red, and white light conditions. The results showed that the growth of the two lines were similar until tillering stage, but other developmental stages from heading to senescence were much delayed in Bd21-3, which resulted in increased height and tiller numbers. Under different light conditions, primary leaf lengths were kept increasing during the growth period, whereas the coleoptile extension was inhibited 4 to 7 days after growth depending on the light conditions applied. These results suggest that the responses to light in B. distachyon can be examined by measuring coleoptile lengths approximately 7 days after seedling growth. Moreover, we selected light-responsive genes known in Arabidopsis thaliana, such as chlorophyll A/B binding protein (CAB), light-harvesting chlorophyll binding protein (Lhcb) and chalcone synthase (CHS), and confirmed their light-induced gene expression in B. distachyon. Therefore, the present study suggests that the inhibition of coleoptile growth can be used as the parameter to analyze photoresponses in the monocot model plant, and also provide the reference genes whose expression is induced by far-red and red light treatment.

• 한국작물학회지
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• 제44권2호
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• pp.149-153
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• 1999

Prediction of rice developmental stage is necessary for proper crop management and a prerequisite for growth simulation as well. The objectives of the present study were to find out the relationship between the plastochrone index(PI) and the developmental index(DVI) estimated by non-parametric phenology model which simulates the duration from seedling emergence(DVI=0) to heading(DVI=l) by employing daily mean air temperature and daylength as predictor variables, and to confirm the correspondency of developmental indice to panicle developmental stages based on this relationship. Four japonica rice cultivars, Kwanakbyeo, Sangpungbyeo, Dongjinbyeo, and Palgumbyeo which range from very early to very late in maturity, were grown by sowing directly in dry paddy field five times at an interval of two weeks. Data for seedling emergence, leaf appearance, differentiation stage of primary rachis branch and heading were collected. The non-parametric phenology model predicted well the duration from seedling emergence to heading with errors of less than three days in all sowings and cultivars. PI was calculated for every leaf appearance and related to the developmental index estimated for corresponding PI. The stepwise polynomial analysis produced highly significant square-rooted cubic or biquadratic equations depending on cultivars, and highly significant square-rooted biquadratic equation for pooled data across cultivars without any considerable reduction in accuracy compared to that for each cultivar. To confirm the applicability of this equation in predicting the panicle developmental stage, DVI at differentiation stage of primary rachis branch primordium was calculated by substituting PI with 82 corresponding to this stage, and the duration reaching this DVI from seedling emergence was estimated. The estimated duration revealed a good agreement with that observed in all sowings and cultivars. The deviations between the estimated and the observed were not greater than three days, and significant difference in accuracy was not found for predicting this developmental stage between those equations derived for each cultivar and for pooled data across all cultivars tested.

• The Plant Pathology Journal
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• 제30권2호
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• pp.125-135
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• 2014

A population model of bacterial spot caused by Xanthomonas campestris pv. vesicatoria on hot pepper was developed to predict the primary disease infection date. The model estimated the pathogen population on the surface and within the leaf of the host based on the wetness period and temperature. For successful infection, at least 5,000 cells/ml of the bacterial population were required. Also, wind and rain were necessary according to regression analyses of the monitored data. Bacterial spot on the model is initiated when the pathogen population exceeds $10^{15}cells/g$ within the leaf. The developed model was validated using 94 assessed samples from 2000 to 2007 obtained from monitored fields. Based on the validation study, the predicted initial infection dates varied based on the year rather than the location. Differences in initial infection dates between the model predictions and the monitored data in the field were minimal. For example, predicted infection dates for 7 locations were within the same month as the actual infection dates, 11 locations were within 1 month of the actual infection, and only 3 locations were more than 2 months apart from the actual infection. The predicted infection dates were mapped from 2009 to 2012; 2011 was the most severe year. Although the model was not sensitive enough to predict disease severity of less than 0.1% in the field, our model predicted bacterial spot severity of 1% or more. Therefore, this model can be applied in the field to determine when bacterial spot control is required.

• Journal of Plant Biotechnology
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• 제33권1호
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• pp.57-62
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• 2006

본 연구에서는 옥수수를 대상으로 glyphosate에 대한 여러 가지 생리적 반응을 검토한 후, glyphosate 저항성 평가에 활용될 수 있는 보다 개선된 방법 두 가지를 확립하였다. 한 가지 방법은 옥수수 제3엽 상단에 약제를 국소 처리한 다음, 처리 후 3일째에 약제처리 되지 않았던 제4엽의 신장 정도를 조사하는 것이다 (전식물체-엽생장 검정). 이 경우 glyphosate $50-1,600{\mu}g/mL$ 범위에서 농도가 증가됨에 따라 엽 생장이 억제되었으며, $1,600{\mu}g/mL$ 농도에서의 생장 억제율은 무처리 대비 55.5%였다. 다른 한 가지 방법은 옥수수 제3본엽의 엽절편 ($4{\times}4mm$) 4개씩을 $200{\mu}L$의 시험용액이 담긴 48 well plate에 치상한 후 $25^{\circ}C$ 연속 명조건에 24시간동안 배양하여 shikimate 축적량을 조사하는 것이다 (엽절편-shikimate 축적 검정). 이 경우 시험용액에 0.33% sucrose를 가하면 무첨가에 비해 약3-4배 정도의 shikimate 축적 증가가 관찰되었고 glyphosate $2-8{\mu}g/mL$ 농도범위에서 직선적 증가반응을 나타내어 기존방법 (Shaner et al. 2005)보다 개선된 특징을 보였다. 본 방법들은 glyphosate 저항성 옥수수를 창출할 때 또는 저항성 유전자의 타 식물로의 이동여부와 잡초화된 저항성 옥수수 존재여부를 감별하는데 활용될 수 있을 것이다. 이 때 glyphosate에 대한 저항성 원인이 작용점 EPSPS와 관련이 있는 경우에는 "엽절편-shikimate 축적 검정"이 가장 바람직하고, 저항성 원인이 체내이행 감소 때문일 경우에는 "전식물체-엽생장 검정" 수행이 필요하다.

• 한국조리학회지
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• 제19권4호
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• pp.1-12
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• 2013

본 연구는 저지방 양념 돈육에 구아바 잎 분말을 첨가하여 천연 연육제로서의 효과를 확인하고 소비자의 욕구를 충족시킬 수 있는 최적의 첨가량을 찾아보고자 양념 돈육의 수분, pH, 색도, 기계적 품질 특성, 관능적 특성(정량적 묘사분석, 기호도 검사)을 측정하였다. 수분은 가열육의 경우 생육보다 상대적으로 낮은 수분함량을 보였으며 구아바 첨가량 1% 첨가 군에서 가장 높게 나타났다. pH는 생육은 1%, 1.5%에서 높은 값을 나타내었고 구운 고기에서는 대조군, 1%, 2%에서 높은 값을 나타내었다. 생육과 구운 고기의 명도는 1% 첨가 군에서 높은 값을 나타내었고 첨가량이 증가할수록 b값의 황색도는 높아졌지만 a값의 적색도는 낮아짐을 확인했다. 텍스처 특성에서 탄력성은 1% 첨가 군에서 가장 높았고, 그 밖의 씹힘성, 경도, 검성은 1%와 1.5%에서 가장 낮은 값을 보이며 첨가율 증가에 따른 연육효과를 확인했다. 정량적 묘사분석에서 갈색은 구아바 잎 분말 첨가율의 증가에 따라 갈색이 강하게 나타났으며, 고기 누린내는 대조군이 가장 높았고 구아바 잎 분말 첨가량이 많을수록 누린내가 약하게 나타났다. 구수한 향미, 연도와 다즙성, 쫄깃한 정도에서는 모두 구아바 잎 분말 1.5%첨가 군에서 가장 높게 나타났다. 종합적 기호도에서 가장 좋게 평가된 시료는 구아바 잎 분말 첨가 1.5%였다. 따라서 본 연구에서 구아바 잎 분말 1.5% 첨가했을 때 가장 높은 효과와 기호도를 확인할 수 있었으며, 이것은 향후 돈육의 소비불균형의 해결과 기능성 재료로서의 연육 연구에 대한 기초자료로 활용될 수 있을 것으로 사료된다.

• 한국초지조사료학회지
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• 제8권1호
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• pp.26-32
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• 1988

This study was conducted to determine the effects of cutting frequency and cutting height on agronomic characteristics and yield performance of sorghum-sudangrass hybrid, cv. Pioneer 855 F on the experimental field of Livestock Experiment Station, Suweon. The results are summarized as follows: 1. The relative contribution of leaf component to total yield was higher when the plants were cut frequently rather than when defoliated only a few times, and tend to be higher with high cutting. 2. Leaf Area Index (LAI) was the highest at the primary growth of two cutting times scheme and the first regrowth for three or four cutting times a year, but LAI, in general, was not related to cutting height. 3. Crop Growth Rate was the heighest at the first regrowth-plants grown in summer, and it was also related to the amount of stubble left at the previous cut. 4. Dead stubbles were not occurred when plants were cut before heading, but those were accompanied by the frequent and low cutting. 5. Total fresh fodder and dry matter yield were the highest at two times cut a year, and decreased with frequent cutting. The optimum cutting height at two times cut was ca. lOCm height stubble from the ground level, but yield increased with higher level cutting at the three or four times cut a year.

• Journal of Plant Biotechnology
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• 제36권3호
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• pp.236-243
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• 2009

The halophyte Leymus chinensis (Trin.) is a perennial rhizome grass (tribe Gramineae) that is widely distributed throughout China, Mongolia and Siberia. This study was conducted to investigate an optimal condition for plant regeneration from mature seeds, leaf base segments, and root segments in L. chinensis. Plant growth regulators affecting embryogenic callus induction and plant regeneration were investigated by four-factor-three-level [L9 (34)] orthogonal test in this study. The effects of explants types (mature seeds, leaf base segments and root segments), callus types, medium types were examined in this study. Wild type (WT) and Jisheng No. 1 plants (JS) were used for primary callus induction. A clear explants difference was seen during callus induction; mature seeds were considered as the preferred explants; and the highest frequency of callus induction was obtained in Medium 6 using mature seeds as explants in WT. Plant regeneration ability was evaluated by frequencies of green callus forming, shooting, rooting, and shooting with roots. Effect of α-naphthalene acetic acid (NAA) on shoot regeneration was remarkable with the highest frequency of 70.8% in WT after 2-month culture. The medium with 0.2- 0.5 mg/L NAA was found to have the highest shoot induction. All regenerated shoots were successfully rooted when transferred on half-strength Murashige and Skoog (MS) basal medium. The acclimatized plantlets were grown to mature with flowering and seeds setting in green house conditions.

• 식물병연구
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• 제13권1호
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• pp.30-33
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• 2007

석량풋콩 품종의 콩밭에서 모자이크 증상이 약하게 나타난 186개의 잎을 채집하여, Cowpea mosaic virus(CPMV)에 대한 ELISA 검정을 하였다. 그 결과 93개의 시료가 양성반응을 보였으며, 이 가운데 55개의 시료는 매우 높은 바이러스 밀도를 나타내고 있었다. 이러한 결과는 석량풋콩 품종의 동부모자이크병은 ELISA 검정, 바이러스 순화, 전자현미경검경 결과와 바이러스 표피 단백질분석 결과 Cowpea mosaic virus에 의한 병해로 확인되었다.

• The Plant Pathology Journal
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• 제39권2호
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• pp.181-190
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• 2023

The fungal pathogen Pseudocercospora fuligena, known to affect tomatoes in the tropics and subtropics, has been reported from temperate climates including the United States and Turkey in recent years. In this study, an isolate from fresh tomatoes and the disease it causes were characterized and infection mechanisms investigated. Macroscopically, both sides of tomato leaves show indistinct effuse patches but prolific production of fuliginous lesions is conspicuous on the abaxial side first but also on the adaxial side later on as infection progressed. Microscopically, fascicles of conidiophores (11-128 ㎛ × 3.5-9 ㎛) arising from stromata and conidia with up to 12 septations were observed. Molecular characterization of the isolate revealed high homology (99.8%) to other P. fuligena isolated from tomatoes in Turkey. Out of the 10 media tested, P. fuligena grew significantly well and sporulated better on unsealed tomato oatmeal agar and carrot leaf decoction agar, both supplemented with CaCO₃. Direct transfer of conidia from profusely sporulating lesions was the easiest and quickest method of isolation for in-vitro studies. Light and scanning electron microscopy on cleared and intact tomato leaves further confirmed stomatal penetration and egress as well as prevalence of primary and secondary infection hyphae. In situ, blocked stomatal aperture areas of 154, 401, and 2,043 ㎛² were recorded at 7, 12, and 17 days after inoculation, respectively. With the recent expanded horizon of the pathosystem and its consequential impact, such studies will be useful for a proper diagnosis, identification and management of the disease on tomato worldwide.

• 한국식품영양과학회지
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• 제33권8호
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• pp.1246-1251
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• 2004

본 실험은 사염화탄소 독성에 대한 몇 가지의 식물소재들- 솔잎, 콩나물, 인진쑥, 표고버섯 - 의 간보호 효과를 조사하기 위하여 수행되었다. 우선적으로 일차 간세포 배양실험에서 식물추출물(열수 또는 에탄올)을 첨가(20 mg/mL 배지)하고 2시간 후에 사염화탄소를 처리(50$\mu$L)한 결과, 배지내의 AST와 ALT 효소활성은 다음과 같았다. 솔잎은 에탄올 및 열수 추출물(P<0.05)에서, 표고버섯은 열수 추출물(p<0.01∼0.05)에서, 그리고 콩나물과 인진쑥은 추출방법에 따라 유의성 있는(p<0.01) 감소를 보였다. 또한, 3주간의 식물 추출물을 첨가한 사료를 사전급여하고 사염화탄소를 2일간 복강주사(1 mg/kg 체중)한 동물실험에서 혈청내의 AST 및 ALT 활성은 간세포 배양의 결과와 유사하게 솔잎과 콩나물에서 낮은 활성효과(p<0.01)를 보였다. 정상군에 대한 사염화탄소의 투여는 지질과산화물과 cytochrome P-450의 함량, 그리고 xanthine oxidase(XOD) 활성을 크게 증가시켰다. 그러나 식물소재 중에서 솔잎, 콩나물, 인진쑥 등을 추출물을 첨가한 실험군에 대한 사염화탄소 처리는 일반적으로 지질과 산화와 XOD 활성증가를 억제하는 것(p<0.01)으로 나타난 반면에, cytochrome P-450의 함량 증가는 솔잎과 인진쑥의 첨가군에서 관찰되었다. 따라서 본 실험에서 cytochrome P-430의 함량증가에 대한 식물 추출물들의 효과는 확실하지 않았지만, 솔잎과 콩나물의 추출물은 항산화관련 실험에서 대부분 탁월한 효과를 나타내었다.