• Asian-Australasian Journal of Animal Sciences
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• 제7권3호
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• pp.303-316
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• 1994

Microbial digestion of feed in the rumen involves a sequential attack culminating in the formation of fermentation products and microbial cells that can be utilized by the host animal. Most feeds are protected by a cuticular layer which is in effect a microbial barrier that must be penetrated or circumvented for digestion to proceed. Microorganisms gain access to digestible inner plant tissues through damage to the cuticle, or via natural cell openings (e.g., stomata) and commence digestion from within the feed particles. Primary colonizing bacteria adhere to specific substrates, divide to form sister cells and the resultant microcolonies release soluble substrates which attract additional microorganisms to the digestion site. These newly attracted microorganisms associate with primary colonizers to form complex multi-species consortia. Within the consortia, microorganisms combine their metabolic activities to produce the diversity of enzymes required to digest complex substrates (e.g., cellulose, starch, protein) which comprise plant tissues. Feed characteristics that inhibit the microbial processes of penetration, colonization and consortia formation can have a profound effect on the rate and extent of feed digestion in the rumen. Strategies such as feed processing or plant breeding which are aimed at manipulating feed digestion must be based on an understanding of these basic microbial processes and their concerted roles in feed digestion in the rumen.

• 한국조경학회지
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• 제27권1호
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• pp.122-131
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• 1999

Indoor environments are usually less than optimal for the growth of ferns, especially in regards to the water condition. These studies were performed to investigate responses involved in causing growth of ferns and presume management plan against the water deficit under indoor conditions. The effect of air humidity and soil moisture on the ferns was examined in Adiantume raddianum and Selaginella kraussiana. Results of experiments are as follows; 1. Under a low humidity condition, having a 25-50% RH. ornamental value of ferns decreased much more than under a 90% RH. Under a low soil moisture, such as sand treatment, ornamental value of ferns also decreased. 2. Leaf chlorophyll content, water content and stomata situations increased as air humidity and soil moisture went up. 3. Even if air humidity and soil water were not enough for ferns growth, the extending of irrigation cycle was helpful. 4. Under extremely low air humidity conditions, some water management, namely, using water holding soil or extending of irrigation cycle was desirable. Other methods of increasing air humidity, including water instruments such as ornamental pools, waterfalls, or fountains, grouping plants together were also helpful. But spraying water on leaves increased injury to ferns growth because of excess evaporation from the leaves. Though these studies, we learn that ferns are susceptible to water condition such as air humidity, soil water and water management. If other environmental factos are maintained with optimal conditions, water condition plays an important role in ferns growth in indoor environments.

• 한국작물학회지
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• 제27권2호
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• pp.175-181
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• 1982

사양토에서 인삼생육의 최적 토양 함수량 구명키 위해 토양함수량별 지상하부, 생식생장, 광합성 등을 조사한 바 그 결과는 다음과 같다. 1. 근건물중 및 동직경은 62%(절대수분 13.9%)가 가장 양호하였다. 2. 엽면적, 엽건물중은 62%(절대수분 13.9%)가 가장 양호하였으며 개체당 개화수, 결실율, 종자생산량도 같은 경향이었다. 3. 단위 면적당 광합성량은 토양 함수량이 많을수록 증가하였으나 개체당 광합성량은 62%가 가장 양호하였다. 4. 증산량은 토양함수량과 비례하였으나 기공의 밀도는 반비례하였다.

• Natural Product Sciences
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• 제10권4호
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• pp.168-172
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• 2004

In India, Gymnema sylvestre due to the unique property of the plant to antagonize the sweet taste is known as 'Gur-mar'. It has several ethnomedicinal values as various tribals/traditional communities and rural peoples of India find diverse medicinal uses viz. antidiabetic, stomachic, diuretic, and is useful in cough and throat troubles. Besides, it has strong effect on reducing blood sugar. The present communication deals with the detailed pharmacognostical evaluation of the aerial parts of G. sylvestre collected from three places of the country-Varanasi (U.P), Panchmarhi (M.P), Salem (Tami Nadu) and commercial sample procured from local market. The botanical and physico-chemical parameters of all the samples were quite similar though little variations were observed in foaming index, alcohol and water soluble extractives of local sample. The microscopic characteristics of the drug are horse shoe shaped petiole with 3 amphicribal vascular bundles, sieve tubes well developed; anomocytic stomata only on the abaxial surface of the leaf, the fan shaped amphicribal vascular bundle, presence of intraxylary phloem. The TLC fingerprint profile of all the samples was more or less similar only the quantity of some of the compounds varied.

• 식물분류학회지
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• 제45권4호
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• pp.299-305
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• 2015

Huperzia lucidula (Michaux) Trevis.의 동북아시아 집단 및 북미 집단을 대상으로 외부형태와 포자형태를 비교한 결과 잎의 형태, 엽연부, 잎에서의 기공의 분포 및 포자의 형태에 있어서 뚜렷히 구분되었다. 따라서, 동북아시아 집단을 북미 지역의 H. lucidula와는 독립된 종 H. asiatica (Ching) B.-Y. Sun and J. Lim으로 분리, 승격하였다. 또한, H. serrata (Thunb.) Trevis.와 동일 종 또는 종내 분류군으로 인식되어 오던 H. javanica (Sw.) C. Yang은 영양엽에서 엽병의 발달 유무, 엽연 거치의 수 그리고 무성아가지의 중앙 열편 모양으로 별개의 종으로 처리하는 견해를 지지하였다.

• Journal of Plant Biotechnology
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• 제33권2호
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• pp.117-122
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• 2006

Comparative studies on medium supply in bioreactors (raft, immersion and ebb and flood) have revealed that multiplication and growth of Alocasia Amazonica were greatest in the raft system, while lowest in ebb and flood system. In the raft system, the basal part of the shoots was continuously in contact with medium, which enabled a constant uptake of nutrients as well as aeration to the explants. The number and the size of leaf stomata were higher in the raft system compared with immersion and ebb&flood system. In the immersion system, plantlets were deformed and epidermal cells in leaves were irregular with a large intercellular space. The results suggested that the medium supply should be controlled properly to maintain normal and healthy plantlets during liquid cultures in bioreactors Which affects morphology and physiology Of the plantlets.

• 한국작물학회지
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• 제26권1호
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• pp.45-50
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• 1981

Diurnal changes in leaf stomatal resistances were measured on leaf positions and both surfaces to investigate the stomatal response to irradiance in wheat, var. Chokwang and barley, var. Dongbori 1. Stomatal frequency and size were also determined to explain the control mechanism of gas exchanges in two species. The leaf diffusive resistances of two species decreased, as the sun rose, to minimum at 10 to 11 o'clock a.m. and increased gradually in the afternoon, even faster at sunset. As the adaxial irradiance increased, stomatal resistances decreased sensitively in the range of 30uEm$^{-2}$ㆍsec$^{-1}$ to 150uEm$^{-2}$ㆍsec$^{-1}$ quantum flux density. The stomatal opening of the abaxial surface began at lower irradiance and was completed earlier than the adaxial surface. The adaxial irradiances decreased in order of leaf position, flag, the 2nd, the 3rd leaf, and the stomatal resistances increased in the same order. Even under the same irradiance, the stomatal resistance of lower leaves were higher than those of upper leaves. The stomatal frequencies of lower leaves were less, but the stomatal size was greater than those of upper leaves. Consequently, the relative leaf area occupied by stomatal pores were constant among leaf positions in two species.

• Journal of Plant Biotechnology
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• 제37권4호
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• pp.539-548
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• 2010

Potassium ($K^+$) is one of the most abundant cations in higher plant. It comprises about 10% of plant dry weight and it plays roles in numerous functions such as osmo- and turgor regulation, charge balance of plasma membrane and control of stomata and organ movement. Several potassium transporters and potassium channels regulate $K^+$ homeostasis in response to $K^+$ uptake systems. In this review, we describe the biological, biochemical and physiological characteristics of shaker like potassium channels in higher plant. Especially, we searched the rice genome databases and analysized expressed genes, genome structures and protein domain characteristics of shaker like potassium channels.

• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2011년도 학술발표회
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• pp.7-10
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• 2011

The semi-arid and arid regions comprise almost 40 percent of the world's land surface. The low and erratic precipitation pattern is the single most significant contributor for limiting crop production in such regions where rainfall is the source for surface, soil and ground water. In a changing climate, the semi-arid and arid regions would increasingly face the challenge of water scarcity. According to the relevant literature; under the assumption of a doubling of the current atmospheric CO2 concentration, irrigation demand was estimated to increase for wheat and to decrease for second crop maize in a Mediterranean environment of Turkey in the 2070s. Crop evapotranspiration would decrease due to stomata closure. Reference evapotranspiration and potential soil evaporation were projected to increase by 8.0 and 7.3%, respectively, whereas actual soil evaporation was predicted to decrease by 16.5%. Drainage losses below 90 cm soil depth were found to decrease mainly due to lesser rainfall amount in the future.

• 한국자원식물학회지
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• 제14권3호
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• pp.188-195
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• 2001

삽주(Atractylodes japonica Koidz. ex Kitam.)와 큰꽃삽주(A. macrocephala Koida.)의 근경 과 측근, 줄기, 잎과 엽병, 자방, 잎의 표피 세포의 형태와 크기에 관한 해부학적형질을 조사하여 이들의 분류학적 가치를 평가하고자 본 연구를 수행하였다. 줄기와 자방의 횡단면 구조는 매우 유사하여 두 종이 구분되지 않았으나, 근경에 분포하는 유관의 크기와 단위면적 당 분포수, 잎과 엽병의 횡단면 형태, 잎 표피 세포의 크기와 기공의 단위 면적당 분포수에서 차이가 있어 두 종을 구별하는 형질로서 가치가 있는 것으로 생각되었다.