• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.185-190
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• 2003

Gamma irradiation was used as part of a new processing method to produce a brighter-colored and mild-flavored green tea leaf extract that retained all of its physiological activities. Dried green tea leaf was extracted with 70% ethanol and gamma irradiated at 0,5, 10, 20 kGy. Hunter color $L^{*}$- and $a^{*}$-values were increased with irradiation in a dose-dependent manner, which was a color range from dark brown to bright yellow. However, the irradiation effect gradually disappeared during 3 weeks of storage, with color reverting to that of untreated samples. There was no difference in the radical scavenging and tyrosinase inhibition effect by irradiation. Among antioxidants used, ascorbic acid was the most effective against color reversion. In contrast, cysteine was shown to protect the effect of color change with irradiation. Results indicated that enhanced color of irradiated green tea leaf extract can be effectively controlled by additives such as ascorbic acid and a low storage temperature.e.e.

• 한국작물학회지
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• 제55권3호
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• pp.259-267
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• 2010

This study was performed at Rice and Winter Cereal Crops Department of NICS during 2007 and 2008 to investigate the characteristics of rice leaf emergence and to obtain basic data which can be used for rice growth simulation model by which we can forecast rice growth stage and heading date accurately under different cultivars, transplanting date, and climatic conditions. To confirm leaf emergence rate according to rice maturing ecotype, we surveyed the leaf emergence rate and heading date of Unkwangbyeo, Hwayoungbyeo and Nampyeongbyeo which are early maturing, medium maturing and medium-late maturing cultivars, respectively, according to seedling raising duration and transplanting time. When seedling duration was 15 days, the growth duration between transplanting time and completion of flag leaf emergence on main culm were 51.5~78.3 days in Unkwangbyeo, 55.3~87.9 days in Hwayoungbyeo and 58.4~98.4 days in Nampyeongbyeo, respectively. When seedling duration was 30 days, they were 50.1~75.5 days in Unkwangbyeo, 52.4~84.7 days in Hwayoungbyeo and 56.4~93.8 days in Nampyeongbyeo, respectively. As transplanting time delayed, the emerged leaf number after transplanting decreased in all rice cultivars. The cumulative temperature between transplanting time to completion of flag leaf elongation on main culm were $1,281^{\circ}C{\sim}1,650^{\circ}C$ in Unkwangbyeo, $1,344^{\circ}C{\sim}1,891^{\circ}C$ in Hwayoungbyeo and $1,454^{\circ}C{\sim}2,173^{\circ}C$ in Nampyeongbyeo, respectively. Leaf emergence rate on main culm were precisely represented by equation, y = $y_0$ + a / [1 + exp( - (x - $x_0$) / b)]^c, when we used daily mean temperature as variable.

• 한국작물학회지
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• 제22권2호
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• pp.23-26
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• 1977

본시험은 새로 육성된 품종에 대하여 유묘기 저온장해양상 및 그 품종간 차이를 엽기별로 검토하여 저온하에서의 수도안전재배 및 신품종육성의 기초자료로 활용코자 16개신품종을 공시하여 2,4,6엽기에 주야간 $10-5^{\circ}C$의 저온처리를 하여 시험을 실시했던바 그 결과를 요약하면 다음과 같다. 1. 저온처리에 의하여 초장신장이 심하게 억제되었으며 japonica품종보다는 $indica{\times}japonica$품종에서 심하였다. 2. 저온처리완료후에 식물체를 정상온도에 옮겼을 때 2일까지는 장해가 증가하였으나 그 이후에는 2일째와 큰 차이가 없었다. 3. 고사율을 보면 japonica보다는 $indica{\times}japonica$ 품종들이 저온에 대한 피해를 많이 입었으며 "통일", "수원251", "수원277호"는 중정도의 피해를 받았다. 4. 저온장해는 엽기에 따라 품종간 그 반응이 다르게 나타났으며 4엽기에서 가장 심하게 나타났다.이 다르게 나타났으며 4엽기에서 가장 심하게 나타났다.

• 한국환경과학회지
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• 제16권11호
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• pp.1313-1318
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• 2007

Illicium anisatum was bred under four different light intensity. Those condition were full sunlight(PPFD $1600{\mu} mol\;m^{-2}s^{-1}$), 30% treatment(PPFD $400{\mu} mol\;m^{-2}s^{-1}$), 50% treatment(PPFD $250{\mu} mol\;m^{-2}s^{-1}$) and 70% treatment(PPFD $100{\mu} mol\;m^{-2}s^{-1}$), respectively. Chlorophyll a and b were increased according to decrease of light intensity. Thirty percent and 50% treatment had not significant different in chlorophyll a and b. Thirty percent treatment was shown the best photosynthetic activity through invested photosynthetic rate, intercellular $CO_2$ concentration and water use efficiency. Photosynthetic activity trend of 50% treatment was similar to 30% treatment. Seventy percent treatment was shown the best photosynthetic activity at low light intensity but that was decreased to lower value than 30% and 50% treatment under high intensity. Control, bred full sunlight, was shown the worst photosynthetic activity at measured all light intensity. That result could imply that was caused by photo-inhibition because of long term exposed of shade tolerant plant at high light intensity. Leaf characteristics had not significant different in leaf length, width and area but leaf dry weight had similar trend to photosynthetic activity.

• International Journal of Industrial Entomology and Biomaterials
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• 제21권1호
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• pp.133-137
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• 2010

The perilla leaf pyralid moth, Pyrausta panopealis Walker (Lepidoptera: Pyralidae), is a serious pest damaging to leaf perilla. In order to establish the life parameters of P. panopealis for eventual purpose of control, the developmental span of each stage was investigated under five temperature regimes ($20^{\circ}C{\sim}30^{\circ}C$). The larval period of P. panopealis was longest as 26.8 days at $20^{\circ}C$ and shortened as temperature goes up to $30^{\circ}C$ as 11.3 days. Survivorship of the larval P. panopealis was the highest at $27.5^{\circ}C$ as 82.5%, whereas that of other temperatures ranged from 40% ($20^{\circ}C$) to 60.0% ($30^{\circ}C$), indicating that the P. panopealis appears to favor somewhat higher temperature. In addition to larval period, the duration of egg, prepupal, and pupal period also were shortened sharply as temperature goes up, whereas the duration of adult stage shortened a maximum of only two days as temperature goes up. After the perilla leaf pyralid moths were successfully stabilized in indoor environment the larvicidal efficacy of ten on-the-market environmentfriendly agricultural materials (EFAMs) that were previously selected from the result of other moth species was tested. Seven of the ten tested showed more than 90% of mortality within 12 hrs and reached nearly up to 100% within 24 hrs, but the remaining three showed less than ~70%.

• 생물환경조절학회지
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• 제7권1호
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• pp.25-33
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• 1998

겨울철 오이 시설재배에서 태양열 시스템을 이용한 지중가온의 효과를 구명하고자 지중 40 cm에 15 mm의 PPC파이프를 130 cm이랑 에 4열 매설한 후 지중 20 cm의 지온을 $22~23^{\circ}C$로 설정한 후 1996년 11월 7일부터 1997년 1월 30일까지 일정한 온도로 유지, 관리하여 무가온구와 가온구의 지상부, 지하부 및 수량을 비교시험한 결과는 다음과 같다 1) 지중가온에 의한 지온확보는 가온구는 15~20 cm에서 $22^{\circ}C$ 정도의 평균온도를 확보할 수 있었고, 무가온구는 평균 $17~18^{\circ}C$ 정도였다 2) 정식 30일 정도에서 초기생육은 가온구가 초장, 경경, 엽수, 엽면적 등 모두 증가하였으며 특히 초장 27%, 엽수 51%, 엽면적은 150% 정도 증가하였다. 또 지상부 평균 증가율도 관행대비 가온구 증가율이 117% 정도였다. 3) 가온구의 지하부 뿌리의 생장성이 관행구에 비하여 평균 56% 정도 증가하였다 4) 과수의 수량면에서도 총과수가 무가온구 313개, 가온구 614개로 가온구가 196% 정도 증수되었다.

• 한국응용곤충학회지
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• 제51권3호
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• pp.235-243
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• 2012

중요 시설해충인 아메리카잎굴파리(Liriomyza trifolii (Burgess))의 개체군 밀도변동모형을 방울토마토 온실내 대기온도와 잎 표면온도를 이용하여 모형 정확성을 비교하였다. 모형 개발에 이용된 생물적 변수들은 기존 발표된 자료들을 사용하였고 모형 작성은 DYMEX$^{(R)}$ 프로그램을 이용하였다. 온도에 따라 상이한 발육기간과 산란수는 생리적 연령으로 표준화시킨 발육완료 분포모형, 연령 특이적 산란수 및 생존율을 비선형회귀 모형에 적합시켜 밀도변동 모형을 개발하였다. 줄내림방식의 방울토마토에서 식물체를 3개의 위치(상단: 지상 1.6 m 이상, 중단: 지상 0.9 - 1.2 m 사이, 하단: 지상 0.3 - 0.5 m 사이)로 나누고 각 위치별로 온실 내 대기 온도와 잎 표면 온도를 기록하였다. 온실 내 잎 표면 최대온도는 대기중 최대온도보다 항상 낮게 유지되고 있었으며, 하단, 상단, 중단의 순으로 온도가 낮아지는 경향을 보였다. 개발된 모형검정을 위한 초기이입 시기와 밀도는 6월초 성충 5마리가 총 50개의 알을 잎에 산란한 것으로 설정하였다. 온실 내 대기 온도와 잎 표면 온도를 이용하여 아메리카잎굴파리 유충 발육모형과 성충의 산란모형을 DYMEX로 프로그래밍하고 모의실험을 하였다. 모의실험결과를 평가하기 위해 기상자료를 수집한 동일한 온실에서 아메리카잎굴파리 유충 밀도를 육안조사 하였으나, 알, 번데기, 성충의 경우 육안조사가 어려워 대상에서 제외하였다. 육안조사결과 밀도변동패턴이 방울토마토 잎 표면 온도를 이용한 모의실험결과 밀도변동패턴과 유사하였다. 육안조사결과와 육안조사시기의 DYMEX모의실험 결과값을 상관분석 한 결과, 육안조사결과와 잎 표면 온도를 이용한 모의실험 결과가 유의한 양의 상관관계를 보였다(r = 0.97, p < 0.01). 대기 온도를 이용한 모의실험 결과와는 유의하지 않은 상관관계를 보였다(r = 0.40, p = 0.18). 본 연구결과 방울토마토 온실에서 아메리카잎굴파리 개체군 밀도변동의 적절한 예측을 위해서는 잎 표면 온도를 고려해야 하는 것으로 나타났다.

• 한국자원식물학회지
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• 제11권2호
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• pp.119-123
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• 1998

Effects of elevated CO2 and temperature on nitrogen (N) uptake , leaf N concentration, N partitioning , N use efficiency (NUE) and grain yield of pot and field grown rice (Oryza sativa. L.cv. Chukwangbyeo) under canopy-like conditions were studied over three years. Rice plants were grown in pots and in the field in temperature gradient chambers containing either ambient(350ppm) or elevated CO2 concentrations (690 or 650ppm) in conbination with either four or seven temperature regimes ranging form ambient temperature(AT) to AT plus 3$^{\circ}C$. There were three N supplies 94g or 6g m-2 to 20g or 48g m-2.Elevated CO2 increased N uptake in field-grown rice ; the magnitude of this effect was thelargest (+15%) at the highest N level. However, in pot-grown rice, N uptake was suppressed with the effect was the largest at high N levels. Leaf N concentration declined at elevated CO2 mainly due to a decrease in N partitiioning to the leaf blades. Air temperature had little effect on the N parameters mentioned previously, wherease NUE for spikelet production declined rapidly with increased temperature irrespective of CO2 concentration. The response of the biomass to elevated CO2 varied with N level, with the greatest response at 20g N m-2 (+30%) . At AT, where high temperature-induced sterility was generally not observed, elevated CO2 increased yield. However, the magnitude of this effect varied greatly (2-39%) with N level, and was mainly dependent on the magnitude of the increase in spikelet number.

• 한국작물학회지
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• 제23권1호
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• pp.1-4
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• 1978

단백질구성 변화를 여러가지 온도조건에서 Japonica형인 진흥, Indica$\times$Japonica교잡품종인 통일, 밀양 2003, 영남조생, 유신등을 공시하여 'Growth Cabinet'를 사용하여 검토 하였던바 다음과 같은 결과를 얻었다. 1. 저온하에서 엽록소함양감소는 Japonica형 품종보다 Indica형 품종에서 심하였다. 2. 단백질구성비(저분자가용성단백질에 대한 고분자가용성단백질의 비)는 고온하에서 높았고, 저온하에서 낮았다. 3. 품종간 단백질구성비는 저온하에서 Japonica형 품종보다 Indica형 품종이 낮았다. 4. 엽신의 엽록소함양과 가용성단백질구성비와는 정의 유의 상관관계가 인정되었다.관계가 인정되었다.

• Journal of Ecology and Environment
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• 제43권2호
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• pp.98-103
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• 2019

We compared the functional traits of leaf blades and culms of common reed (Phragmites australis) in four habitat types of distinguished environments such as temperature, precipitation, water characteristics, and indices related to biomass production (montane fen, MF; riparian marsh, RM; lagoon, LG; and salt marsh, SM). We also examined the relationships between the functional traits within and among populations. Four populations showed remarkable differences in the functional traits of leaf blades and culms. MF and RM had relatively tall (> 300 cm) and thick (> 8 mm) culms bearing long leaf blades (> 40 cm), whereas LG and SM had relatively shorter and thinner culms bearing shorter leaf blades than MF and RM. Some relationships between the functional traits of leaf blades and culms showed negative or not significant correlations within the population, whereas most of the relationships between the functional traits showed positive correlations particularly when all the data from four populations was included into the correlation analysis.