• 농업과학연구
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• 제41권2호
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• pp.75-83
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• 2014

Recently, a quick drop of air temperature in plastic film houses by adverse weather conditions leads to the occurrence of low temperature damages to growing crops. Chilling injury, defined as a variety of growth restriction occurring below the optimal temperature, is one of environmental factors strongly affecting crop growth and yield. Low temperature causes the restricted evapotranspiration, reduced mineral uptake (P > K > $NO_3{^-}$), and an increase in electrolyte leakage such as K. Despite being different with plant species, an accumulation of soluble carbohydrates such as glucose, fructose, sucrose and starch under chilling condition is well known. A variety of environmental stresses are known to cause oxidative damage to plants either directly or indirectly by triggering an increased level of production of reactive oxygen species (ROS), and, to combat the oxidative damage, plants have the antioxidant defense systems comprising of enzymes, SOD, POD, CAT, GPX and APX, and non-enzymes, ascorbate, gluthathione, ${\alpha}$-tocopherol, phenolic compounds, carotenoid and flavonoids. The aim of this review is to provide basic information to build chilling-indicators and optimal nutrition management under adverse temperature conditions as broadly considering mineral uptake, carbohydrate metabolism and antioxidative defense system.

• Journal of Microbiology and Biotechnology
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• 제15권1호
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• pp.131-135
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• 2005

Under sulfur deprived conditions, PS II and photosynthetic $O_2$ evolution by Chlamydomonas reinhardtii UTEX 90 are inactivated, resulting in shift from aerobic to anaerobic condition. This is followed by hydrogen production catalyzed by hydrogenase. We hypothesized that the photosynthetic capacity and the accumulation of endogenous substrates such as starch for hydrogen production might be different according to cell age. Accordingly, we investigated (a) the relationships between hydrogen production, induction time of sulfur deprivation, increase of chlorophyll after sulfur deprivation, and residual PS II activity, and (b) the effect of initial cell density upon sulfur deprivation. The maximum production volume of hydrogen was 151 ml $H_2$/l with 0.91 g/l of cell density in the late-exponential phase. We suggest that the effects of induction time and initial cell density at sulfur deprivation on hydrogen production, up to an optimal concentration, are due to an increase of chlorophyll under sulfur deprivation.

• The Plant Pathology Journal
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• 제35권4호
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• pp.313-320
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• 2019

Rye was used here to dissect molecular mechanisms of resistance to Fusarium head blight (FHB) and to go deeper with our understanding of that process in cereals. F. culmorum-damaged kernels of two lines different in their potential of resistance to FHB were analyzed using two-dimensional gel electrophoresis and mass spectrometry to identify resistance markers. The proteome profiling was accompanied by measurements of ${\alpha}-$ and ${\beta}-amylase$ activities and mycotoxin content. The proteomic studies indicated a total of 18 spots with clear differences in protein abundance between the more resistant and more susceptible rye lines after infection. Eight proteins were involved in carbohydrate metabolism of which six proteins showed a significantly higher abundance in the resistant line. The other proteins recognized here were involved in stress response and redox homeostasis. Three remaining proteins were associated with protease inhibition/resistance and lignin biosynthesis, revealing higher accumulation levels in the susceptible rye line. After inoculation, the activities of ${\alpha}-$ and ${\beta}-amylases$, higher in the susceptible line, were probably responsible for a higher level of starch decomposition after infection and a higher susceptibility to FHB. The presented results could be a good reference for further research to improve crop resistance to FHB.

• Journal of Ginseng Research
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• 제47권3호
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• pp.469-478
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• 2023

Background: Nitrogen (N) is an essential macronutrient for plant growth and development. To support agricultural production and enhance crop yield, two major N sources, nitrate and ammonium, are applied as fertilizers to the soil. Although many studies have been conducted on N uptake and signal transduction, the molecular genetic mechanisms of N-mediated physiological roles, such as the secondary growth of storage roots, remain largely unknown. Methods: One-year-old P. ginseng seedlings treated with KNO₃ were analyzed for the secondary growth of storage roots. The histological paraffin sections were subjected to bright and polarized light microscopic analysis. Genome-wide RNA-seq and network analysis were carried out to dissect the molecular mechanism of nitrate-mediated promotion of ginseng storage root thickening. Results: Here, we report the positive effects of nitrate on storage root secondary growth in Panax ginseng. Exogenous nitrate supply to ginseng seedlings significantly increased the root secondary growth. Histological analysis indicated that the enhancement of root secondary growth could be attributed to the increase in cambium stem cell activity and the subsequent differentiation of cambium-derived storage parenchymal cells. RNA-seq and gene set enrichment analysis (GSEA) revealed that the formation of a transcriptional network comprising auxin, brassinosteroid (BR)-, ethylene-, and jasmonic acid (JA)-related genes mainly contributed to the secondary growth of ginseng storage roots. In addition, increased proliferation of cambium stem cells by a N-rich source inhibited the accumulation of starch granules in storage parenchymal cells. Conclusion: Thus, through the integration of bioinformatic and histological tissue analyses, we demonstrate that nitrate assimilation and signaling pathways are integrated into key biological processes that promote the secondary growth of P. ginseng storage roots.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.107-107
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• 2022

The increase in atmospheric temperature due to climate change prolongs the period of exposure to high-temperature environments during rice cultivation. In particular, high-temperature during early seed development greatly affects on the productivity and quality of rice. The high temperature at this time not only affects the transport and distribution of assimilates from leaves to seeds and the accumulation of starch in the seeds, but also affects the leaves, which are the production organs of assimilates, and increases the consumption of assimilation products due to an increase in respiration. Therefore, in this study, rice was grown in temperature gradient chambers(TGC) to analyze the effects of high temperature on physiological responses, assimilate production, and changes in gene expression in rice leaves. Analysis of chlorophyll and sugar contents and RNA-seq experiments were performed using flag leaves collected under normal and elevated temperature conditions, respectively, during the early seed development stage, and then these results were comprehensively discussed.

• 한국초지조사료학회지
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• 제5권3호
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• pp.180-186
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• 1985

본(本) 시험(試驗)은 옥수수와 sorghum식물(植物)에서 생육시기(生育時期) 및 환경온도(環境溫度)가 Weender성분(成分) 및 Net Energy Lactation 에 미치는 영향(影響)을 구명(究明)코자 옥수수의 Biizzard와 sorghum hybrids와 Pioneer931 및 Sioux를 공시품종(供試品種)으로 하여 뮌헨대학교초지연구소(大學校草地硏究所)에서 포장(圃場) 및 phytotron시험(試驗)으로 실시(實施)하였다. Phytotron의 주(晝)/야간(夜間) 실내온도(室內溫度)는 30/25, 25/20, 28/18 및 $18/8^{\circ}C$로 하였으며 일조(日照)는 35,000Lux로 13시간(時間) 조사(照謝)하였다. 1978-'81년간(年間) 얻어진 결과(結果)를 요약(要約)하면 다음과 같다. 1. 옥수수 및 sorghum의 crude protein은 3 엽기유식물(葉期幼植物)의 경우 각각(各各) 31.4% 및 33.9%에 이르나 생육(生育)이 진전(進展)됨에 따라 급속도(急速度)로 하락(下落)되어 출수기(出穗期)에는 9.0%(옥수수) 및 10.4% (sorghum)로 감소(減少)된다. 식물체내의 protein축적(蓄積)과 LWR 및 LAR간(間)에는 높은 정(正)(+)의 상관(相關)이 있다.($P{\leq}0.1%$). 2. 조섬유(粗纖維)의 합성(合成) 및 축적(蓄積)은 유수형성기(幼穗形成期)에서 지엽출현기(止葉出現期)에 본격적(本格的)으로 이루어지며 그 함량(含量)은 출수기(出穗期)에 각각(各各) 옥수수 28.4% 및 Sorghum 31.5%로 최고농도수집(最高濃度水準)에 달한다. 그러나 옥수수의 경우 조섬유(粗纖維) 함량(含量)은 종자(種子)가 성숙(成熟)됨에 따라 다시 감소(減少)되어 황숙기(黃熟期)에는 19.5%까지 감소(減少)되는데 반(反)해 sorghum 식물(植物)에서는 계속적(繼續的)으로 증가(增加)하는 경향(傾向)이 있다. 3. NEL 함량(含量)은 3 엽기(葉期)의 유식물(幼植物)에서 옥수수 5.98MJ 및 sorghum 5.64MJ/kg으로 높은 편이나 생육(生育)이 진행(進行)되는 동안 감소(減少)되어 유수(幼穗)가 형성(形成)되는 6-8 엽기(葉期)에 각각(各各) 5.82MJ(옥수수) 및 5.46MJ/kg(sorghum)으로 최저수준(最低水準)을 나타낸다. 옥수수의 NEL 함량(含量)은 그후 종자(種子)가 성숙(成熟)됨에 따라 6.70MJ(乳熟期) 및 6.94MJ/kg(完熟期)까지 증가(增加)되는데 비해 sorghum에서는 증가폭(增加幅)이 완만하여 계속(繼續) 낮은 수준(水準)을 유지(維持)한다. 4. 옥수수 및 sorghum식물(植物)의 NEL가치(價値)는 fruetosan, mono- 및 disaccharose등 non-structural carbo-hydrate의 합성(合成) 및 축적형태(蓄積形態)에 의(依)해 큰 영향(影響)을 받으면 NEL함량(含量)과 cell-wall constituents간(間)에는 부(負)(-)의 상관(相關)이 있다.($P{\leq}0.01%$). 5. NEL 및 starch value 환경온도(環境溫度)가 상승(上昇)됨에 따라 감소(減少)된다. 4 엽기(葉期) sorghum식물(植物)의 환경온도(環境溫度)를 달리 하였을 때 NEL가치(價値)는 각각(各各) 4.87MJ($30/25^{\circ}C$), 5.46MJ($25/20^{\circ}C$) 및 5.81MJ/kg($18/8^{\circ}C$)로 변(變)하여 고온(高溫)에서 net energy lactation 축적(蓄積)이 크게 감소(減少)되었다.

• 한국환경농학회지
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• 제38권1호
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• pp.38-46
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• 2019

BACKGROUND: Salinity is one of the main environmental stresses deteriorating qualities as well as yields of food crops. This study was conducted to identify the effects of salt stress on dry matter ratio, glucose content, and mineral content and composition in potatoes (Solanum tuberosum L.). METHODS AND RESULTS: Four potato varieties were grown in plastic pots (diameter 20 cm and height 25 cm) with three salinity levels (EC: 1.0, 4.0, and 8.0 dS/m) in a glasshouse. Dry matter ratio, specific gravity, starch, and glucose content in tubers harvested at 90 days after sowing were analyzed. Also, mineral contents (T-N, T-C, $P_2O_5$, $K^+$, $Ca^{2+}$, $Mg^{2+}$, $Na^+$) in stem, leaf, and tuber were investigated and statistically analyzed for analysis of variance (ANOVA). Dry matter ratio, specific gravity, and starch content in tubers were reduced in all varieties as the salt concentration increased. Glucose content tended to decrease according to the salt concentration. In ANOVA analysis of mineral contents, there were significant differences in $K^+$ and $Mg^{2+}$ of leaf and stem, in $Na^+$ of leaf and tuber, and also in $Ca^{2+}$ of leaf by the interactions of variety and salinity. In the case of $K^+/Na^+$ and $Ca^{2+}/Na^+$, the stem was more sensitively influenced by the salt treatment than the leaf or the tuber. The $K^+/Na^+$ and $Ca^{2+}/Na^+$ decreased in leaf, stem, and tuber of four varieties, as the salt concentration became higher. The decreasing level varied according to the varieties. 'Kroda' and 'Duback' maintained relatively higher $K^+/Na^+$ and $Ca^{2+}/Na^+$ than 'Atlantic' or 'Goun' under the salt stress conditions. CONCLUSION: The composition and accumulation of minerals in potato plant as well as dry matter ratio, starch, and glucose contents were significantly influenced by salt stress. The respond patterns were different depending on the varieties and it was related to the salt tolerance among varieties.

• 한국작물학회지
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• 제59권2호
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• pp.194-200
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• 2014

고구마 괴근의 표피에 선모양으로 돌출되어 나타나는 피맥의 발생동향을 조사하고, 경감하기 위한 시험의 결과는 아래와 같다. 1. 고구마 피맥은 표피가 줄무늬로 돌출되어 상품성을 저하시키는 증상으로서 피맥발생은 표피층에 전분이 집적되어 발생하는 것으로 관찰되었고, 조기재배보다 보통기재배에서 발생이 많았다. 2. 고구마 품종에 따른 피맥발생은 건풍미, 연황미, 건미 등 7품종이 3%이하로 적었고, 헬씨미, 보라미는 30%이상 발생하였다. 만중은 피맥발생과 정의 상관관계가 있었다. 3. 고구마 피맥은 생육기간이 진전됨에 따라 증가하다가 삽식 후 120일경에 가장 높았다. 4. 고구마 삽식 후 90일의 적심비율에 따른 피맥발생율은 일정한 경향을 보이지는 않았다. 엽면적지수 4에서 피맥발생율이 가장 적었으나, 일정한 경향을 보이지는 않았고, 경엽절제비율이 높을수록 수량감소가 크게 나타났다.

• 생물환경조절학회지
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• 제25권4호
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• pp.255-261
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• 2016

복숭아 '미홍' 품종의 토양 수분 스트레스에 의해 나타나는 지상부의 생리적 반응을 구명하기 위해 본 연구를 수행하였다. 잎의 변색, 위조, 낙엽의 순서로 침수와 무관수에 의해 반응이 나타났으며 가지의 기부에서 시작되어 선단부로 확대되었다. 가지의 길이 및 직경 생장이 두 처리구에서 모두 감소되었고 침수에 의한 낙엽이 심하게 발생되었다. 침수에 의해 뿌리의 수분 흡수와 잎의 광합성과 호흡이 감소되었다. 잎의 엽록소가 두 처리구에서 모두 감소되었다. 침수처리구에서는 육안으로 변화가 없던 잎에서도 엽록소가 감소한 것이 해부학적으로 관찰되었다. 전분은 침수와 무관수에서 모두 감소되었고 탄수화물은 침수처리구의 뿌리에서 감소되었다. 침수는 수분의 흡수나 이동이 불량해지고, 광합성능력의 감소와 낙엽이 발생되었다. 결국 저장양분이 부족해져 고사되거나 내한성 약화로 저온피해의 가능성이 높은 것으로 판단되었다. 복숭아 재배에서 수분 스트레스에 의한 피해를 방지하기 위해 관수에 유의하고 배수시설을 설치하여 토양조건을 개선하는 것이 요구된다.

• Journal of Plant Biotechnology
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• 제38권4호
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• pp.263-271
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• 2011

벼는 세계 인구의 60%에 의해 소비되고 있는 주요 식량작물이며 그 종자의 주성분은 탄수화물로 인류의 중요한 에너지원이 된다. 미곡(米穀)은 주식으로 다량 섭취하게 되는데 특히 동물성 단백질의 섭취가 부족한 국가 또는 지역에서는 쌀 단백질이 콩 단백질과 함께 중요한 영양공급원이 되고 있어 벼의 종자단백질은 인류에 매우 중요한 영양성분이라 할 수 있다. 그런데 벼의 종자단백질은 필수아미노산인 라이신이 부족하므로 아미노산 조성 변경에 의한 영양적인 개량이 요구되기도 하는 한편 선진국에서는 혈압조절이나 면역증강 등 생리기능을 가진 건강증진용 기능성 단백질 또는 펩티드로 주목받고 있다. 따라서 벼의 종자단백질의 조성변경과 더불어 이종의 저장단백질의 도입에 의한 벼 종자단백질 개량 연구가 진행되어 왔다. 본 총설에서는 벼의 종자 저장단백질의 생합성과 축적 특징 및 저장단백질 집적의 유전적 제어 기작에 대하여 알아보고 또한 벼 종자 저장단백질 조성 변경, 이종단백질 도입에 의한 벼 종자 저장단백질 개량 연구 현황을 기술하고자 한다.