• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.3
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• pp.159-166
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• 2013

We have previously investigated the proteome changes of rice leaves under heat stress (Lee et al. in Proteomics 2007a, 7:3369-3383), wherein a group of antioxidant proteins and heat shock proteins (HSPs) were found to be regulated differently. The present study focuses on the biochemical changes and gene expression profiles of heat shock protein and antioxidant genes in rice leaves in response to heat stress ($42^{\circ}C$) during a wide range of exposure times. The results show that hydrogen peroxide and proline contents increased significantly, suggesting an oxidative burst and osmotic imbalance under heat stress. The mRNA levels of chaperone 60, HSP70, HSP100, chloroplastic HSP26, and mitochondrial small HSP responded rapidly and showed maximum expression after 0.5 or 2 h under heat stress. Transcript levels of ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR) and Cu-Zn superoxide dismutase (Cu-Zn SOD) showed a rapid and marked accumulation upon heat stress. While prolonged exposure to heat stress resulted in increased transcript levels of monodehydroascorbate reductase, peroxidase, glyoxalase 1, glutathione reductase, thioredoxin peroxidase, 2-Cysteine peroxiredoxin, and nucleoside diphosphate kinase 1, while the transcription of catalase was suppressed. Consistent with their changes in gene expression, the enzyme activities of APX and DHAR also increased significantly following exposure to heat stress. These results suggest that oxidative stress is usually caused by heat stress, and plants apply complex HSP- and antioxidant-mediated defense mechanisms to cope with heat stress.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.1
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• pp.7-15
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• 1993

Nitrogenous and non structural carbohydrate compounds in the remaining tissues of 10 weeks old alfalfa (Medicago sativa L.) grown in hydroponic culture, were analysed during 24 days of regrowth following shoot removal. The dry weights of the remaining organs were not significantly changed for 10 days following shoot removal. Compared with uncut plants, defoliation drastically depressed root growth, in particular that of taproot. During 6 days of regrowth, nitrogen contents in all remaning organs significantly decreased. Nitrogen loss in this period was pronounced in root system. Nitrogen contents in each organ after 24 days of regrowth in defoliated plant were recovered completely or exceeded initial level. Amino acid-N was the most readily available form of nitrogen while protein-N was the largest storage pool. The tap root contained about 51.0% and 33.4%, respectively, of the total starch and total ethanol-soluble sugar contents. The starch content of tap roots initially exceeded 40.7 mg. plant$^{-1}$ (day 0), and then declined to the minimum level on day 14. This result clearly showed that the tap root is the major storage site for metabolizable nitrogen (protein-N and amino acid-N) and carbohydrate(starch), and that the degradation of these researves occur much actively in the early period of regrowth.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.1
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• pp.16-22
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• 1993

Ladino clover stolen growing in grazed sward transplanted in 1/5,000a Wagner pot with two rows and were grown in green house with 12h lighting. Fifty days after transplanting the first cutting was made, the secound and 3rd cutting was made 20 days after each harvest. Treatment were nitrogen fertilization level of 2.5, 5.0 and 7.5 kg N/10a. Nitrogen was top dressed after transplanting and each cutting. Growing point, above and under ground DM yield, nitrogen fixation, crude protein of stolon, root and change of acetylene reduction activity after cutting were investigated. Result are as follows. 1. Growing point, DM production were heighst in 5 kg N at the first and 2nd harvest while 2.5 kg at 3rd cutting. Plants with 7.5 kg N/10a were dead at 3rd harvest. There were significant differences in growing point between treatment. 2 Nitrogen fixation of ladino clover were the heightest in 2.5 kg N pot at 1st cutting and as cutting and N fertilization were contiuned nitrogen fixation activity was lowered. 3. Leaf have more crude protein than that of stolen and root while plant crude protein increased by 2nd cutting as plant got more nitrogen fertilizer and again decreased in 3rd cutting. 4. Acetylene reduction activity were lowest at 3 week and recovered normal level at 5 week after cutting, also DM root was same trend.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.3
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• pp.64-129
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• 1992

최근 초지중심 사양형태의 증가와 초지면적의 확대에 따라 단순한 사료로서가 아니라 영양가치가 높고 기호성이 높은 목초생산이 요구되고 있다. 그러나, 고위생산을 위해 다량으로 사용된 질소질비료에 의하여 질산태 중독 등의 문제가 야기되고 있어 목초의 생리 및 영양에 관한 연구가 필요하게 되었다. 사료성분 혹은 영양가치에 대한 연구는 이미 일찍부터 다루어져 왔으나, 주로 야초류, 청예작물 및 농가부산물 등의 일반성분 특히, 조단백질과 조섬유함량의 연구가 주가 되었고 다년생 목초류에 대한 연구는 1975년경부터 본격화 되기 시작하였다. 그동안 한국초지학회지와 축산학회지($1972\sim1991$)에 게재된 총 151편의 생리 및 영양에 관한 연구 중에서 다년생 목초류를 취급한 것은 불과 63편에 머물고 있다. 이 분야의 연구는 각종 목초 사료작물에 대한 재배조건과 생육단계에 따른 생리생태학적 연구와 사료성분, 소화율 및 가소화양분 함량의 일반적인 변화, 경향을 검토하여 사료 가치 평가를 위한 기준으로 삼았다. 그러나 다년생 목초류는 물론 사료 작물에 있어서 육종 생리분야의 연구는 매우 미흡한 상태로써 단지 발아, 생육, 저장탄수화물 및 유독성분 등 단편적인 연구만이 행해지고 있을 뿐이다. 또한 사료 성분이 가축의 기호성에 미치는 영향을 구명하기 위한 연구는 거의 이루어지고 있지 않으므로 금후 탄수화물과 미량 요소에 대한 자세한 연구 검토가 필요하다고 생각된다. 특히 목초와 사료작물의 화학적인 조성과 가축의 생리에 관련한 여러가지 문제들도 앞으로 보다 깊이 연구되어야 할 과제라고 생각된다.권을 잡기 위해 10년지기였던 IBM과 MS사는 각각 OS/2와 윈도즈를 내세우고 양보할 수 없는 힘겨루기에 들어갔다. 또 이들 양사는 펜컴퓨터,멀티미디어등 차세대제품의 운영체제 시장을 둘러싸고 일찍부터 격전에 들어갔으며 IBM과 MS사의 혼전을 틈타 썬마이크로시스템을 필두로한 워크스테이션 업체 및 유닉스진영까지 고성능 PC시장을 겨냥한 OS를 속속 개발, 90년대의 OS 전쟁은 한치 앞을 내다볼 수 없는 안개국면으로 접어들고 있다. DOS에서 32비트시대,펜컴퓨터, 멀티미디어에 이르는 차세대제품을 둘러싼 업계의 OS 쟁탈전을 통해 OS의 발전동향과 미래를 전망해 본다. results in the large change of the objective function, the sum of squares of deviations of the observed and computed groundwater levels. 본 논문에서는 가파른 산사면에서 산사태의 발생을 예측하기 위한 수문학적 인 지하수 흐름 모델을 개발하였다. 이 모델은 물리적인 개념에 기본하였으며, Lumped-parameter를 이용하였다. 개발된 지하수 흐름 모델은 두 모델을 조합하여 구성되어 있으며, 비포화대 흐름을 위해서는 수정된 abcd 모델을, 포화대 흐름에 대해서는 시간 지체 효과를 고려할 수 있는 선형 저수지 모델을 이용하였다. 지하수 흐름 모델은 토층의 두께, 산사면의 경사각, 포화투수계수, 잠재 증발산 량과 같은 불확실한 상수들과 a, b, c, 그리고 K와 같은 자유모델변수들을 가진다. 자유모델변수들은 유입-유출 자료들로부터 평가할 수

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.3
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• pp.223-228
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• 2011

The present study was conducted to determine the optimum in vitro culture condition for callus induction and plant regeneration from mature seeds of bermudagrass (Cynodon dactylon cv. Common). It was revealed that mature seeds cultured on MS medium supplemented with 2 mg/L 2,4-D, 0.5 g/L proline, 0.5 g/L casamino acid and 3 g/L Gelrite under light condition produced the highest percentage of callus formation (39.2%). The most suitable medium for plant regeneration from dehydrated calli was MS agar medium supplemented with 0.5 mg/L 2,4-D, 2 mg/L BA, 0.5 g/L proline, 0.5 g/L casamino acid 3 g/L Gelrite which induced the highest percentage of calli forming shoots (57.7%). The frequency of callus induction and plant regeneration were the highest on sucrose, followed by maltose. The shoots were rooted at the highest rate (100%) when transferred onto 1/2 MS medium. Regenerated plants were morphologically uniform with normal growth pattern.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.3
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• pp.217-222
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• 2011

Success in molecular breeding for better adapted varieties to environmental stresses depend upon the concerted efforts by various research including tissue culture, transformation, genetics and breeding. In order to optimize tissue culture conditions of Siberian wildrye grass, the effects of plant growth regulators on callus induction and plant regeneration were investigated with mature seeds. The highest callus induction frequency was observed when the mature seeds were cultured on MS medium supplemented with 5 mg/L 2,4-D. The highest plant regeneration frequency was observed when callus was transferred to N6 medium supplemented with 1 mg/L 2,4-D and 3 mg/L BA. Regenerated plants were grown normally when shoots were transplanted to the soil. A short tissue culture period and regeneration system would be beneficial for molecular breeding of Siberian wildrye grass by the production of transgenic plant.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.76-88
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• 2011

The flora of vascular plants in the mountains located in the Uiryeong-gun area, in the South province of the Korean Peninsula, such as Jagul-san(897.1 m), 676 Highland(676 m), Byeokhwa-san(522 m), and the Bangeo-san(530.4 m), was investigated between April 2008 and August 2009. These investigations found 580 taxa consisting of 496 species, 1 subspecies, 77 varieties, and 6 forms, found within 319 genera under 103 families. The count totaled at 744 taxa(16.2% of all vascular plant taxa in Korea), which was made up of 648 species, 3 subspecies, 81 varieties, and 12 forms, found within of 362 genera under 109 families, when voucher specimens from the previous research studies were added. Forests of the investigated areas were generally composed of mixed Pinus densiflora and Quercus sp. The areas with comparatively excellent vegetation were the valley neighboring Baekun-sa(temple) (in the eastern slope of Mt. Jagul-san), the southwest slope of Mt. 676 Highland, the eastern slope of Mt. Byeokhwa-san, and the northern slope of Mt. Bangeo-san. 10 families were collected in abundance: Compositae, Graminae, Leguminosae, Liliaceae, Rosaceae, Cyperaceae, Labiatae, Polygonaceae, Ranunculaceae, and Violaceae these families made up 50% of all collected taxa. 19 taxa were endemic to the area, including Salix hallaisanensis H.Lev, S. koriyanagi Kimura, Aconitum austrokoreense Koidz, A. pseudolaeve Nakai, Clematis trichotoma Nakai, Thalictrum uchiyamai Nakai, Stewartia pseudocamellia Maxim, Philadelphus schrenkii Rupr., Lespedeza ${\times}$ robusta Nakai, Vicia chosenensis Ohwi, Euonymus trapococca Nakai, and Angelica cartilagino-marginata var. distans(Nakai) Kitag. Eight of the taxa were rare and endangered plants, as designated by the Korea Forest Service, including Jeffersonia dubia(Maxim.) Baker & S. Moore and Viola diamantiaca Nakai. 38 taxa of alien plants were found. Vegetation of the surveyed areas falls in the South province of the Korean Peninsula. Of all the taxa collected, 463 taxa(10.06% of all vascular plants in Korea) are considered useful plants, 231 taxa are edible, 193 taxa have medicinal uses, 65 taxa are used ornamentally, 234 taxa are important forage, 3 taxa are used as an industrial raw material, 17 taxa are used for timber, 18 taxa contain useful dyes, and 7 taxa are used for fiber.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.6
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• pp.651-654
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• 2016

A number of accidents relating to highly toxic hydrogen fluoride (HF) or hydrofluoric acid (HA) release have occurred over fast few decades in Korea. Thus, this study was conducted to investigate the fluoride (F) concentrations in paddy soil and brown rice from 2 different areas where the soils were exposed to HF and HA. In the first case, the HF leakage accident that occurred in 2012 affected the surrounding soils and crops and consequently, crops (rice) affected by HF were unavailable for forage even though F did not accumulate in the soil. For example, at the time of accident, F concentrations in brown rice samples were $33.0-1,395mg\;kg^{-1}$, while F concentrations in soil samples were $155-295mg\;kg^{-1}$ which were less than the Korean standard guideline values of $400mg\;kg^{-1}$. However, after a year, F concentrations in brown rice were observed below the detection limit ($1mg\;kg^{-1}$), although F concentrations in soils were similar with those in 2012. Also, large amounts of wastewater discharges containing HA occurred in 2013 and some agricultural soils exceeded the Korean standard guideline values for F ($400mg\;kg^{-1}$), but soil-plant F transfer was not observed. In conclusion, it was observed that soil to plant transfer of F is unlikely although HF and HA as gas or liquid form can cause direct damage to plants.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.1
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• pp.30-37
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• 2016

Microalgae are functional foods because they contain special anti-aging inhibitors and other functional components, such as ecosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and omega-3 polyunsaturated fatty acids. Many of these functional dietary components are absent in animals and terrestrial plants. Thus, microalgae are widely utilized in human functional foods and in the feed provided to farmed fish and terrestrial livestock. Many marine organisms consume microalgae, often because they are in an appropriate portion of the cell size spectrum, but also because of their nutritional content. The nutritional requirements of marine organisms differ from those of terrestrial animals. After hatching, marine animals need small live forage species that have high omega-3 polyunsaturated fatty acid contents, including EPA and DHA. Euglena cells have both plant and animal characteristics; they are motile, elliptical in shape, 15-500 μm in diameter, and have a valuable nutritional content. Mixotrophic cell cultivation provided the best growth rates and nutritional content. Diverse carbon (fructose, lactose, glucose, maltose and sucrose) and nitrogen (tryptone, peptone, yeast extract, urea and sodium glutamate) supported the growth of microalgae with high lipid contents. We found that the best carbon and nitrogen sources for the production of high quality Euglena cells were glucose (10 g L^–1) and sodium glutamate (1.0 g L^–1), respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.3
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• pp.325-333
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• 1994

This study was undertaken at Gowa, South Sulawesi, Indonesia as part of a larger forage genetic resource evaluation project. The experimental program consisted of a field experiment where grasses and legume species were grown in monocultures and the yield, N content and rumen bag digestibility using goats were measured. The field experiment was conducted from December 1985 to October 1986. Eight species of legumes (Desmodium heterophyllum cv. John-stone, Desmodium triflorum from Gowa, South Sulawesi, Arachis sp. from Maiwa, South Sulawesi, Clitoria ternalea CPI 50973, Macroptilium atropurpureum ev. Siratro, Neonotonia wightii cv. Tinaroo, Centrosema pubescens CPI 58575, Centrosema plumeri CPI 58568) were grown as monocultures. After establishment all plants were cut to a uniform height of 5 cm, and subsequent cuts were made on regrowth after 14, 28, 42, and 56 days (cycle 1). Cycle 2 commenced towards the end of the wet season and continued for 157 days into the dry season. The highest yielding legumes were C. ternatea in the wet season and Arachis sp. in the dry season. The mean rumen bag dry matter digestibility (RBDMD) of legumes of 67.6% for leaf material (averaged over all cycles and ages) was 7.6% higher than for stem material. The RBDMD of Arachis was significantly higher than all other species. The RBDMD of all legumes declined with age. Calculation of yield of digestible DM (yield $\times$ RBDMD) showed that Arachis sp. was the best legume. The combination of plant "quality" with yield measures is a valuable adjunct to routine agronomic survey procedures in plant evaluation programs. Arachis sp. appears to offer considerable promise and should be more widely evaluated.