• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.8-9
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• 2017

Soybean yield has been low and unstable in Japan and other areas in East Asia, despite long history of cultivation. This is contrasting with consistent increase of yield in North and South America. This presentation tries to describe perspective of breaking stagnation of soybean yield in East Asia, considering the factors of the different yields between regions. Large amount of rainfall with occasional dry-spell in the summer is a nature of monsoon climate and as frequently stated excess water is the factor of low and unstable soybean yield. For example, there exists a great deal of field-to-field variation in yield of 'Tanbaguro' soybean, which is reputed for high market value and thus cultivated intensively and this results in low average yield. According to our field survey, a major portion of yield variation occurs in early growth period. Soybean production on drained paddy fields is also vulnerable to drought stress after flowering. An analysis at the above study site demonstrated a substantial field-to-field variation of canopy transpiration activity in the mid-summer, but the variation of pod-set was not as large as that of early growth. As frequently mentioned by the contest winners of good practice farming, avoidance of excess water problem in the early growth period is of greatest importance. A series of technological development took place in Japan in crop management for stable crop establishment and growth, that includes seed-bed preparation with ridge and/or chisel ploughing, adjustment of seed moisture content, seed treatment with mancozeb+metalaxyl and the water table control system, FOEAS. A unique success is seen in the tidal swamp area in South Sumatra with the Saturated Soil Culture (SSC), which is for managing acidity problem of pyrite soils. In 2016, an average yield of $2.4tha^{-1}$ was recorded for a 450 ha area with SSC (Ghulamahdi 2017, personal communication). This is a sort of raised bed culture and thus the moisture condition is kept markedly stable during growth period. For genetic control, too, many attempts are on-going for better emergence and plant growth after emergence under excess water. There seems to exist two aspects of excess water resistance, one related to phytophthora resistance and the other with better growth under excess water. The improvement for the latter is particularly challenging and genomic approach is expected to be effectively utilized. The crop model simulation would estimate/evaluate the impact of environmental and genetic factors. But comprehensive crop models for soybean are mainly for cultivations on upland fields and crop response to excess water is not fully accounted for. A soybean model for production on drained paddy fields under monsoon climate is demanded to coordinate technological development under changing climate. We recently recognized that the yield potential of recent US cultivars is greater than that of Japanese cultivars and this also may be responsible for different yield trends. Cultivar comparisons proved that higher yields are associated with greater biomass production specifically during early seed filling, in which high and well sustained activity of leaf gas exchange is related. In fact, the leaf stomatal conductance is considered to have been improved during last a couple of decades in the USA through selections for high yield in several crop species. It is suspected that priority to product quality of soybean as food crop, especially large seed size in Japan, did not allow efficient improvement of productivity. We also recently found a substantial variation of yielding performance under an environment of Indonesia among divergent cultivars from tropical and temperate regions through in a part biomass productivity. Gas exchange activity again seems to be involved. Unlike in North America where transpiration adjustment is considered necessary to avoid terminal drought, under the monsoon climate with wet summer plants with higher activity of gas exchange than current level might be advantageous. In order to explore higher or better-adjusted canopy function, the methodological development is demanded for canopy-level evaluation of transpiration activity. The stagnation of soybean yield would be broken through controlling variable water environment and breeding efforts to improve the quality-oriented cultivars for stable and high yield.

• 생물환경조절학회지
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• 제24권2호
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• pp.51-56
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• 2015

규산은 작물의 필수원소에는 포함되어있지 않으나, 화본과 작물을 중심으로 내도복성과 병충해 저항성의 향상, 군락구조 개선에 의한 광합성 능력의 향상 등에서 폭 넓게 그 유용성이 알려져 왔으며, 최근에는 원예작물에서도 규산질 비료의 시용이 수량이나 병충해저항성을 향상시키는 효과가 입증되고 있어 친환경농업 관점에서도 주목을 밭고 있다. 본 실험은 배추 육묘 중 규산질 비료의 시용이 묘소질과 저온, 고온, 건조 등 환경내성에 미치는 영향을 검토하기 위하여 수행하였다. 규산염 처리농도를 8, 16, 32, 64 및 128mM로 설계하여 주 2회 관주 처리 하고, 처리 3주 후에 생육조사 및 스트레스 내성에 대해 평가하였다. 생육조사 결과, 8, 16 및 32m의 농도에서는 대부분의 생육지표가 대조구에 비해 약간 증가하는 경향을 보였으나 8mM처리만 제외하고 통계적 유의차는 나타나지 않았다. 고농도인 128mM의 규산 처리구에서는 모든 생육 지표가 감소하였다. 총 뿌리 면적, 뿌리 길이 및 근단 수는 8, 16 및 32mM의 농도에서 증가했지만 64 및 128mM의 처리구에서는 감소하였다. 규산 처리 농도가 증가함에 따라 증산 속도는 감소한 반면 기공확산 저항은 증가하는 경향을 보였다. 상대적 이온 누출율도 대조구에 비해 규산염 처리구에서 감소되었으나, 처리 농도간 유의차는 나타나지 않았다. 규산처리에 의해 고온과 저온 장해 지표도 감소되었으며, 농도간에는16과 32mM이 가장 효과적이었다. 규산처리에 따라 건조내성도 증가하여 대조구는 단수 후 3일째부터 위조되기 시작하여 5일째는 전 개체가 위조하였으나, 규산처리구는 4일(8, 64, 128 mM) 또는 5일(16과 32mM) 부터 위조가 시작되어 6일(8mM)이나 7일(16, 32, 64및 128 mM)이 지나서야 모든 공시 개체가 위조되었다.

• Journal of Plant Biotechnology
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• 제44권1호
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• pp.69-75
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• 2017

Dormancy-associated protein (DRM)은 식물의 휴면생리에 관여하는 대표적인 단백질로 거의 모든 식물에 보존되어 있다. 최근 DRM 유전자가 비생물적 스트레스 반응에 관여하는 것으로 알려지면서 이 유전자의 특성구명 연구가 여러 식물에서 이루어지고 있다. 그러나 아직까지 나무에서는 DRM 유전자에 대한 연구가 거의 없는 실정이다. 따라서 본 연구에서는 DRM 유전자를 현사시나무(Populus alba ${\times}$ P. glandulosa)에서 분리하여 이를 PagDRM1이라 명명하고, 유전자의 구조와 발현특성을 조사하였다. PagDRM1 유전자는 123개의 아미노산으로 구성된 단백질을 암호화하며, 2개의 영역(Domain I과 Domain II)이 잘 보존되어 있다. PagDRM1은 현사시나무의 염색체에 1 ~ 2 copy가 존재하며, 줄기에서 가장 높게 발현하였고 성숙 잎, 뿌리 및 꽃에서도 높은 발현 수준을 나타내었다. 현탁배양세포의 생장주기에서는 늦은 지수생장기부터 정지기까지 높게 발현하였다. 또한 PagDRM1은 건조와 염 스트레스에 반응하여 발현이 증가하는 것으로 나타났다. 식물호르몬 처리에 의해서는 ABA와 GA 처리에 의한 발현 증가를 나타내었다. 따라서 PagDRM1은 식물의 휴면유도 과정에서 중요한 역할을 할 뿐만 아니라 환경 스트레스 내성에도 기여하는 것으로 생각된다.

• 한국작물학회지
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• 제48권3호
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• pp.238-242
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• 2003

본 연구는 간척지 토양 염농도별(저염; 0.1-0.2%, 중염; 0.3~0.4%)로 분얼기 관개수 염수처리 농도에 따른 벼 생육 및 수량성을 검토하고자 시험한 결과를 요약하면 다음과 같다. 가. 토양 및 관개수 염농도가 높을수록 초장은 짧았고 주당경수도 적었으며, 특히 중염 토양에서 관개수 염농도 0.3% 이상에서는 모두 고사되었다. 나. 토양 및 관개수 염농도가 높을수록 출수는 지연되었으며, 토양 염농도간에는 중염 토양에서 저염 토양보다 2-5일 정도 늦었다. 다. 간장은 관개수 염농도가 높을수록 짧았고 중염 토양이 저염 토양보다 짧았으며. 수장도 같은 경향이었다. 라. 저염토양에서는 관개수 염농도가 높을수록 $\textrm{m}^2$ 당립수가 적고 등숙비율이 낮아, 쌀수량은 민물 관개 수량에 비해 관개수 0.l%는 92%, 0.3%는 84%, 0.5%는 56%, 0.7%는 36% 수준이었다. 중염토양의 쌀수량은 저염토양 민물 관개 수량에 비해 민물 관개는 62%, 0.1% 관개수에서는 30% 수준이었다. 따라서 관개수 염농도가 저염 토양은 0.7%, 중염 토양은 0.3%까지 생육은 가능하나 수량 감소가 커서, 소득지수로 볼때 간척지 쌀 생산 한계 관개수 염농도는 저염 토양은 0.5% 이하에서, 중염 토양은 민물 관개수에서 가능하였다.

• 한국산림과학회지
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• 제109권1호
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• pp.31-40
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• 2020

본 연구는 기후변화와 관련하여 양묘과정에서 온도와 강수 변화에 따른 주요 침엽수의 생존 및 생장 특성 변화를 알아보고자 수행하였다. 소나무와 낙엽송 노지묘(1-0)를 대상으로 대조구 기준 3℃의 온도를 상승시키거나 ±40%의 강수를 조절한 6처리 생육환경[온도 2처리(대조: TC, 증가: TW) × 강수 3처리(대조: PC, 감소: PD, 증가: PI)] 실외 실험구를 조성하였으며, 생존율, 근원경, 묘고, 물질생산량 및 묘목품질지수 변화를 조사하여 이원분산분석을 수행하였다. 소나무는 온도와 강수 처리에 따른 생존율 차이가 없었지만, 강수가 증가할수록 묘목품질지수가 낮아지는 경향을 보였다. 낙엽송은 온도 상승과 강수 감소에 따라 고사율이 증가하였으며, 묘목품질지수는 두 요인 간 상호작용을 보이면서 온도대조-강수증가 처리구에서 가장 낮게 나타났다. 따라서 양묘과정에서 소나무는 강수 증가, 낙엽송은 온도 증가 또는 강수 감소에서 낮은 묘목 생산량과 품질이 예상되며, 기후변화에 따른 두 수종의 특이적 민감도를 확인할 수 있었다. 향후 지구온난화와 가뭄·폭우 등의 강수 변화에 의해 수종별 묘목 생존과 품질의 변화가 예상되기 때문에 각 수종의 생육 반응 특성에 따른 적합한 양묘시업 대응 전략이 필요할 것으로 판단된다.

• 생태와환경
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• 제36권3호통권104호
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• pp.381-388
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• 2003

The fertility of stream water in major streams of the Lake Shihwa Watershed was compared using water analyses and algal growth potential test (AGPT) in typical drought seasons from December 2001 to April 2002, The water quality varied considerably depending on streams. These streams were very rich in inorganic nutrients that the nutrient levels and characteristics of each stream could be easily determined. Through AGPT, 63.6% of growth was observed in the average values of each stream, with non-growth accounting for 36.4%. AGPT results showed that 40.9% of the 22 stations were in hypertrophic condition and 54.5% in eutrophic condition. AGPT values were significantly correlated with TIN, $NH_4$, and SRP (p <0.001); compared to other nutrients, however, they were more related to SRP and $NH_4$. Moreover, the values increased with high concentration of N and P and low N/P ratios. Nonetheless, the values were more dependent on P concentration than N concentration. This suggests that the effect of P on the water quality of lake situated in downstream may serve as a potential indicator of phytoplankton development. Depending on the drainage pattern of streams, the wastewaters of wastewater treatment plant (WwTP) and untreated wastewater (UTW) were found to have 53.4% and 46.6%, respevtively, of TIN, 51.9% and 48.1% of $NH_4$, 62.9% and 37.1% of $NO_3$, 62.6% and 37.4% of SRP, and 44.1% and 55.9% of SRSi. The AGPT value was 51.1% in WwTP wastewater and 48.9% in UTW wastewater, the concentration of WwTP wastewater was slightly higher. For untreated wastewaters flowing into the constructed wetland and into the lake, TIN accounts for 43.0% and 57.0%, respectively, of nitrogen components, $NH_4$ 44.4% and 55.6%, $NO_3$ 39.6% and 60.4%, SRP 53.5% and 46.5%, and SRSi 52.3% and 47.7%, respectively. The AGPT value was 58.0% in the constructed wetland and 42.0% in Lake Shihwa; the concentration in streams flowing into the wetland was slightly higher. Therefore, Persistent and large development of phytoplankton in Lake Shihwa cannot be prevented unless a measure tophytoplankton control is implemented. This is because the concentration of nutrients in specific streams flowing into the lake is very high, even though the inflow of water is low.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.203-203
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• 2017

The Earth's climate is rapidly changing because of increasing carbon dioxide content in atmosphere so, climate prediction models anticipate that earth surface temperature will rise by 3 to $5^{\circ}C$ in next 50 to 100 years. Therefore, frequency of un-expected weather events such as drought, salinity, low or high temperature and flooding etc. will be increasing worldwide. Furthermore, increased atmosphere temperature can influence pests and pathogens spread as well. Therefore, to protect enormous grain loss from unexpected weather conditions, studies related with combine stress conditions like abiotic plus biotic stress condition are really required. Thus, our research focused on physiological responses under combined abiotic and biotic stress condition in rice plant. To induce uniform stress condition, we used NaCl (100 mM) and salicylic acid (0.5 and 1.0 mM SA) as each stress a stimulator. Each artificial abiotic and biotic stress inducer was applied to hydroponically grown rice seedlings alone or together for four day. The data were collected in a time-dependent manner [1, 2, 3 and 4 day(s) after treatment (DAT)] and were matched with our anticipation that shoot length and shoot fresh weight was decreased in solo and combined abiotic and biotic stress condition. The lipid peroxidation content was significantly increased ($1.5{\pm}0.2$ to $2.7{\pm}0.1mg$ mg of $MDA\;g^{-1}FW$) in the first two days in both stress exposed plants, and showed the opposite trend ($0.5{\pm}0.01$ to $0.1{\pm}0.001mg$ of $MDA\;g^{-1}FW$) in last two days under multi stress condition. Superoxide dismutase (SOD) activity did not showed difference in only biotic stress condition (alone 0.5 and 1.0 mM SA) as compared to control however, it was significantly increased in multi stress condition or solo abiotic stress condition whereas, catalase (CAT), and ascorbate peroxidase (APX) activities were significantly decreased in solo biotic and combined abiotic and biotic condition. In particular, both enzymes activities were more decreased in multi stress condition as compared to solo biotic stress condition. The results for relative mRNA expression level of CAT and APX enzymes were in agreement with results of spectrophotometric values. Correlation value between each stress condition and phenotypic data showed that biotic stress condition showed high correlation with activity of CAT and APX whilst, abiotic stress condition revealed significant correlation with SOD activity.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.299-299
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• 2017

Due to the climate changes in Korea, the numbers of both torrential rain events and drought periods have increased in frequency. Water management practice against water shortage and flooding is one of the key interesting for field crop cultivation, and groundwater often serves as an important and safe source of water to crops. Therefore, the objective of this study is to evaluate the effect of groundwater table levels on soil water content and soybean development under two different textured soils. The experiment was conducted using lysimeter located in Miryang, Korea. Two types of soils (sandy-loam and silty-loam) were used with three groundwater table levels (0.2, 0.4, 0.6m). Mean soil water content during the soybean growth period was significantly influenced by groundwater table levels. With the continuous groundwater level at 0.2m from the soil surface, soil water content was not statistically changed between vegetative and reproductive stage, but the 0.4 and 0.6m groundwater table level was significantly decreased. Lower chlorophyll content in soybean leaves was found in shallow water table treatment in earlier part of the growing season, but the chlorophyll contents were non-significant among water table treatments. Groundwater table level treatments were significantly influenced on plant available nitrogen content in surface soil. The highest N contents were observed in 0.6m groundwater table level. It is probably due to the nitrogen loss by denitrification as the result of high soil water content. The length and dry weight of primary root was influenced by groundwater level and thus the highest length and dry weight of root were observed in 0.6m water table level. This result showed that soybean root growth did not extend below the groundwater level and increased with the depth of groundwater table level. The results of this study show that the management of groundwater level can influence on soil characteristics, especially on soil water content, and it is an important practice of to reduce yield loss caused by the water stress during the crop growing season.

• 농촌계획
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• 제23권1호
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• pp.85-96
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• 2017

Existing agricultural reservoirs are considered as alternative source for the water welfare of rural area. In this study, domestic water supply potential of 476 reservoirs, which has storage capacity more than one million cubic meter, out of 3,377 agricultural reservoirs managed by Korean Rural Community Corporation (KRC) were investigated. Among them water quality of 136 reservoirs met the criteria of domestic water source which show less than COD 3 ppm. Available amount for domestic water of reservoirs, which meet the water quality, for ten year return period of drought was analyzed with reservoir water balance model. The results showed that 116 reservoirs has potential for supplementary domestic water supply while satisfying irrigation water supply. Finally, economic analysis using Net Present Value (NPV), Benefit-Cost (B/C) ratio, Internal Rate of Return (IRR), and Profitability Index (PI) methods was also conducted. The analysis showed that 19 reservoirs satisfied economic feasibility when water is provided from reservoir outlet but only 9 reservoirs meet the economic feasibility if water delivered from a reservoir to treatment plant by newly built conveyance canal. In order to supply the domestic water through the agricultural reservoirs managed by KRC, it is necessary to flexibly interpret and operate the 'Rearrangement of Agricultural and Fishing village Act'. Also, it is reasonable to participate in the water service business when there is a supply request from other Ministries. In addition, the KRC requires further effort to change the crop system for saving water and improve efficiency of irrigation systems.

• 생명과학회지
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• 제23권4호
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• pp.487-494
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• 2013

T-DNA가 표지된 집단에서 AlaAT 유전자가 깨어진 돌연변이체(alaat)를 분리하고, AlaAt1 특이 프라이머를 이용하여 유전자형을 결정하였다. Alaat의 표현형은 대조구와 비교해서 생장의 감소를 보였고, 종자 역시 작고 생산성의 감소를 보였다. 돌연변이체의 AlaAT 활성은 거의 검출되지 않았다. 고염 스트레스 하에서 alaat의 반응을 엽록소 형광과 항산화 효소들의 활성 및 RT-PCR을 이용하여 대조구와 비교하였다. 고염, 건조 및 저온과 같은 모든 비생물적 스트레스에 대한 Fv/Fm은 대조구와 alaat 둘 다 감소를 보였으며, 비생물적 스트레스에 대한 엽록소 형광은 거의 유사하였다. 항산화 효소인 peroxidase (POX)의 활성은 고염 스트레스에 의해 대조구는 증가하나 alaat에서는 오히려 감소하였다. RT-PCR에 의한 cAPX, POX 및 AlaAT mRNA의 수준을 분석한 결과, 효소 활성과 마찬가지로 AlaAt mRNA는 alaat에서 나타나지 않았고, POX2 mRNA는 대조구는 약간의 증가를 보이나 alaat는 거의 검출할 수 없었다. cAPX mRNA는 대조구와 alaat 모두 고염 스트레스에 의해 크게 증가하였다. 이 같은 결과는 AlaAT 유전자 기능의 상실은 염 스트레스 하에서 벼 식물의 생장에 대해 광합성능 보다는 항산화 효소, 특히 POX 활성 및 합성을 변화시킬 수 있음을 제안한다.