• Title/Summary/Keyword: Environmental Factors

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A Theoretical Review of Basin Storage Coefficient and Concentration Time Using the Nash Model (Nash 모형을 이용한 유역 저류상수 및 집중시간의 이론적 검토)

  • Yoo, Chul-Sang
    • Journal of Korea Water Resources Association
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    • v.42 no.3
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    • pp.235-246
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    • 2009
  • This study theoretically reviews the basin storage coefficient and concentration time using the Nash model, a simple unit hydrograph theory. First, the storage coefficient and concentration time of Nash instantaneous unit hydrograph (IUH) are derived based on their definitions, whose characteristics as well as their relationship are also reviewed. Additionally, several empirical equations of storage coefficient and concentration time commonly used in Korea are evaluated by comparing them with those for the Nash IUH. Major results of this study are summarized as follows. (1) The concentration time of Nash IUH is approximately linearly proportional to the number of linear reservoirs, but the storage coefficient non-linearly to the square root. That is, if increasing the number of linear reservoirs by four times, the concentration time becomes also increased by about four times, but the storage coefficient only about two times. This result has a special meaning to understand the effect of basin subdivision on the concentration time and storage coefficient. (2) The storage coefficient and concentration time of Nash IUH are not independent each other, so their independent estimation does not make any physical sense. As the concentration time among the two is more sensitive to the number of linear reservoirs, which should be estimated first, then the storage coefficient considering the concentration time estimated. (3) Empirical equations of concentration time can be divided into two groups, one following the linear channel theory and the other not, whose equation forms are also found to be very similar. This result indicates that the characteristic factors dominating the concentration time are very similar, indicating the possibility of its regionalization over a basin with consistent equation forms. (4) Those for storage coefficient like the Russell formulae are found to consider the physical characteristics of a basin, so their unreasonable applications could sufficiently be excluded.

Effects of Water Temperature and Estradiol-17β on the Sex Ratio and Growth of the Japanese Eel, Anguilla japonica (극동산 뱀장어, Anguilla japonica의 성비와 성장에 미치는 수온 및 estradiol-17β의 효과)

  • Kim, Dae-Jung;Lee, Nam-Sil;Kim, Shin-Kown;Lee, Bae-Ik;Seong, Ki-Baik;Kim, Kyung-Kil
    • Journal of Life Science
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    • v.23 no.12
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    • pp.1454-1459
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    • 2013
  • This study investigated the effects that water temperature and the administration of estradiol-17${\beta}$ (E2) had on the sex ratio and growth of the Japanese eel, Anguilla japonica. Glass eels (total length${\fallingdotseq}$6.5 cm) were differentiated into an E2 group and an E2-free group and then they were reared for about four months at three water temperature levels of $20^{\circ}C$, $24^{\circ}C$, and $28^{\circ}C$. The results showed that the young eels survived normally at the rearing water temperature of ${\geq}24^{\circ}C$, and grew to a mean size of 20 cm (total length). In the E2-free group, temperature was not found to increase the sex ratio (feminizing rates); however, the sex ratio of the E2-administrated group was found to be a little higher at a high temperature ($28^{\circ}C$). The growth of the E2 group was lower than the growth of the E2-free group at $24^{\circ}C$ and the E2 concentration levels in the plasma at $24^{\circ}C$ were found to be significant after the end of the E2 administration period (178 days). Therefore, we thought that long-term administration of E2 must be considered to be the reason for growth decline in spite of the prominent sex ratio effect. Our results indicate that temperature was not related to an increase in the feminizing rate (sex ratio) in the Japanese eel, Anguilla japonica, and other environmental factors (rearing density, salinity, etc.) that have the possibility of inducing ovarian differentiation must be investigated.

National Survey of Injury and Poisoning on a Representative Sample Population of Koreans (우리나라 대표적(代表的) 표본인구(標本人口)의 연간(年間) 손상(損傷) 및 중독발생율(中毒發生率)과 역학적(疫學的) 특성(特性))

  • Kim, Joung-Soon;Kim, Sung-Soo;Chang, Sung-Chill
    • Journal of Preventive Medicine and Public Health
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    • v.27 no.3 s.47
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    • pp.447-463
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    • 1994
  • Despite the public health importance of injury and poisoning in terms of its high mortality and incidence, epidemiologic information to be utilized are scarce in Korea. This study was carried out in 1990 on a representative sample population (about 55,000 persons) along with the 6th National Tuberculosis Prevalence Survey in order to estimate the magnitude of injury and poisoning occurrence and to identify its epidemiologic characteristics which can be aided for establishing preventive strategy. Pre-tested and structured Questionnaire was used by trained interviewer to collect data including general information of the person, various information on the injury and poisoning during the past one year such as time and place of its occurrence, its nature and external causes, type of medical institute attended, duration of treatment and outcome of the accident occured. In analysis of the data collected incidence rates per 1000 persons by sex, age group and its nature as well as external causes, and relative frequencies were calculated. The result obtained are as followings; 1. The incidence rate per 1000 was 30 for both sexes, 39 for male and 22 for female, male being 1.8 times more frequent than female. Age adjusted incidences were not much different from the crude rates. Age group specific rate curve showed bimodal shape in both sexes, small peaks in preschool children and higher peaks in older ages. The incidence rate per 1000 people by area was highest in Jeon-bug province (57/1000) and the lowest in Daegu city(11/1000). 2. The place where the injuries occured were road in 46%, within the boundary of house in 25%, and working place in 12% The injuries and poisoning had occured more frequently during the months from March to August of the year than other months. 3. The relatively frequent injuries by its nature were contusion with intact skin surface (19%), fracture of upper limb (13%), open wound of head, neck and trunk (12%) and fracture of lower limb (11%) among males; contusion with intact skin surface (28%), sprains and strains of joints and adjacent muscle (14%), fracture of upper limb (10%) and fracture of lower limb (9%) among females. Higher incidence rate among males than females were fracture of skull (4.5 times), open wound and fractures of limbs ($2{\sim}3$ times). Age specific rate of injuries and poisoning by its nature showed increasing pattern by age in fractures of upper and lower limbs and sprains & strains of joints whereas the age group of 30's showed highest incidence in open wounds of upper limb. Fractures of radius and ulna in upper limb, fractures of tibia & fibula and ankle in lower limb were most frequent among fractures of upper and lower limbs. The frequent injuries among sprains and strains of joints and adjacent muscles were that of ankle, foot and back, and among open wound were that of head and fingers. 4. Relative frequency of injuries and poisoning by external causes showed following order : other accidents (25%), accidental falls (23%), motor vehicle accident (22%) and other road vehicle accident (14%) among males and accidental falls (37%), motor vehicle accident (24%) and other accident (18%) among females. The external causes revealing higher incidences among males than females, were other road vehicle accident (4.8 times), vehicle accident not elsewhere classifiable (4.4 times), accidental poisoning (4.4 times), accidents due to natural and environmental factors (2.8 times), and sucide & self-inflicted injuries (2.8 times). Age specific incidence by external causes for frequent injuries showed that incidence of other accident steadily increased from 10's till age 50's; motor vehicle traffic accident increased from age 20's and dropped after age 60's; on the other hand accidental fall increased strikingly by age. The most frequent external causes among motor vehicle traffic accidents was motor vehicle traffic accident involving collision with pedstrain (69%), pedal cycle accident (30%) and other road vehicle accident (71%) among other road vehicle accidents; falls on same level from slipping, tripping or standing (44%) and other falls from one level to another among accidental falls; accidents caused by machinary (32%) for male and striking against or struck accidentally by objects or person for female among other accidents. 5. Seventy nine percent of the injuries and poisonings were treated in general hospital or hospital/clinic. The duration of treatment ranged from a few days to 123 weeks; the majority(52%) took under 2 weeks, 36% for $3{\sim}8$ weeks and 4% over 21 weeks. 6. The accident resulted in full recovery of normal healthy state in 62%, residual functional defects in 21% and on process of treatment in 16%.

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Study on the Selection of Promising Cultivars with Unique Flower Characteristics in the Recently Developed Cultivars of Rose of Sharon (Hibiscus spp.) for Landscape Uses (최근 국내외에서 육성된 무궁화 127 품종 중 조경적 활용가치가 높은 유망품종 선발)

  • Kim, Kwang-Ho;Lee, Chun-Suk;Kang, Ho-Chul
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.34 no.3
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    • pp.124-139
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    • 2016
  • This study was carried out to characterize 127 recently developed cultivars of Rose of Sharon (Hibiscus spp.) in Korea and foreign Countries for landscape uses. The examined factors were growth characteristics such as tree height of a 1-year grafted plant(cm), plant type, growth habit, leaf characteristics such as shape and size, flower characteristics such as color, shape, size, and red eye during 2014 and 2015 for landscape uses. The results are obtained as follows; In the results of flower color of the 127 recently developed cultivars, pink color with red eye spot, white color with red eye spot, purplish red color with red eye spot, violet purple color with red eye spot, crimson color with red eye spot, asadal, blue color with red eye spot, and white color were distributed. In the flower characteristics, Hibiscus hybrid 'Daewangchun' had the largest flower size of 16.0cm out of the 127 cultivars. H. syriacus 'Antong', 'Lil Kim', and 'Ggoma' were cultivars with smaller flowers than other cultivars. H. syriacus 'Hunjang' had largest red eye, of 5.2cm of length compared to the other cultivars. The cultivars with unique flower color for landscape uses are H. syriacus 'Kwangmyung', 'Nanpa', 'North face', 'Bulsae', 'Bidan', 'Songam', 'Youngchang', 'Jukpeoso', 'Kiho', 'Tamla', 'Hwasoored' and 'Hwanhee'. These flowers had a purplish red color and were developed in Korea. H. syriacus 'Aphrodite', 'Dr. Uemoto', 'Freedom', 'Pink Cup', 'PS 80-1', 'Purpureus Variegatus', 'Red Giant', 'Woodbridge' also had unique flowers with a purplish red color and were introduced from foreign countries. In addition, cultivars with violet pink flowers were H. syriacus 'Ggoma', 'Doturak', 'Myungmi', 'Byunghwa', 'Sancheonyu', 'Taehwa', 'Hikari-hanagasa', and 'Little Kim Violet'. 'Jongmoo' and 'Ruffled Satin' had flowers with crimson color. Therefore, the new cultivars with unique flower colors were a promising cultivars to a woody landscape plant. Cultivars with large flower sizes were Hibiscus hybrid 'Daewangchun', Hibiscus hybrid 'Daemang', and Hibiscus hybrid 'Jina'. H. syriacus 'Ggoma', 'Mibeak', 'Antong', 'Lil Kim', and 'Eunhasu' had small flower sizes. Cultivars with long red eye were H. syriacus 'Hunjang' and H. syriacus 'Hi Lea Red'. Therefore, the new cultivars, Hibiscus hybrid 'Daewangchun', Hibiscus hybrid 'Daemang', Hibiscus hybrid 'Jina' with large flower sizes, H. syriacus 'Ggoma', 'Mibeak', 'Antong', 'Lil Kim', and 'Eunhasu' with small flower sizes, H. syriacus 'Hunjang' and H. syriacus 'Hi Lea Red' with long red eye, were promising cultivars to a woody landscape plant.

A Study on Vascular Plants, Distribution Status and Management Plans of the Cactus Habitat (No. 429 Natural Monument) in Wolryung-ri, Jeju Island (제주 월령리 선인장군락지(천연기념물 제429호)의 관속식물상, 분포실태, 관리방안에 관한 연구)

  • Lee, Cheol-Ho;Jang, Gye-Hyun;Ryu, Tae-Bok;Choi, Byoung-Ki
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.36 no.1
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    • pp.55-66
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    • 2018
  • The cactus habitat in Jeju Island has a phytogeographically specific distribution in the East Asian region, and forms a unique landscape as the only native cactus (Opuntia ficus-indica (L.) Mill.) habitat in Korea. However, there has been no detailed investigation on the distribution of cacti in the habitat and no investigation on the diversity of the mixed composition of plants in the habitats and their correlation with the distribution of cactus populations. This study attempted to investigate the diversity of vascular plants in the Wollyeong-ri cactus habitat and record the actual distribution and trends of cactus distribution. In addition to the distribution characteristics of cacti, we also discuss the characteristics of species reflecting the characteristics of the habitat among the mixed population of plant species, as well as the biological and environmental factors that threaten the maintenance of cactus populations or require management for preservation of cacti. Considering the phenological character, we conducted the field surveys for flora identification six times between June 2015 and September 2017. The Engler classification system was used for the arrangement sequence and names of plants, and the Korean Plant Names Index was adopted for the Korean name of the species. The study results showed that the Wolryung-ri cactus habitat in Jeju Island has the characteristic physiognomy of an area dominated by cactus. For the vascular plants, a total of 125 taxa were identified, including 53 families, 104 genera, 109 species, 15 varieties and 1 forma. Endangered plants specified by the Ministry of Environment were not found. Two species, Cyrtomium falcatum and Asplenium incisum, were identified as the ferns, and no gymnosperms were found. In addition, 123 taxa of angiosperms, 91 taxa of dicotyledones and 32 taxa of monocotyledons were identified. The distributions of cacti were confirmed in 289 meshes corresponding to 59.3% of the total 487 meshes in the cactus protected area, which showed various coverage distributions ranging from 5% to 95%. Most of the meshes where no cacti were found are coastal areas with exposed basalt rocks where the soil depth has not developed or extremely restricted due to repeated waves, or areas where artificial facilities, grasslands, and observation paths have been constructed. On the other hand, there were 71 lattice points in 14.5% of the total area where the cactus showed 70% or higher dominance. Cacti are randomly distributed in these areas. They have adapted to the microhabitat environment and are found to be opportunistically distributed along the growable locations. Considering that the reproduction of cacti in the habitat is mostly dependent on parthenogenesis, the present distribution seems to reflect the potentially distributable regions of cacti in the habitat. Based on the results of field surveys, a management plan for conservation and protection of the protected areas has been proposed.

A Study of Evaluation Index Development of Healthcare Rehabilitation Device Design (헬스케어 재활훈련기 디자인 평가 요소 개발에 관한 연구)

  • Cho, Jae Sang;Kwon, Tae Kyu;Hong, Jung Pyo
    • Science of Emotion and Sensibility
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    • v.17 no.3
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    • pp.129-142
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    • 2014
  • Due to the increase of the aged population and population of the disabled today, there is a growing demand for rehabilitation medical instruments. Furthermore, there is a growing demand for evaluation indices for services that should be provided for uses of the rehabilitation medical instruments. In order to evaluate rehabilitation medical instrument designs in this study, the basic index for design evaluations shall be identified to search for assessment plans. Through this, new evaluation indices will be deduced through discussions and analysis of rehabilitation medical experts, biomedical engineers, and designers. The results of this study are summarized as follows. First, the existing design evaluation indices were collected and analyzed to construct 10 rehabilitation medical instrument design evaluation indices and 44 sub-evaluation items. These will be important evaluation standards for designing rehabilitation medical instruments in the future. Second, the design evaluation indices that must be taken into consideration when developing health care rehabilitation medical instruments are the 10 design evaluation indices of usability, cognition, safety, learning, motility, durability, economic feasibility, space, aesthetics and environmental aspects. Third, design evaluation indices of environment, space, cognition, usability, economic feasibility and aesthetics are indices that must be taken into consideration for product design, while learning, safety, motility and durability are factors that must be given special consideration for rehabilitation medical instrument design evaluation indices. Fourth, if existing product design evaluation indices placed importance on environment, space, cognition, usability, economic feasibility and aesthetics of products for design evaluation indices, rehabilitation medical instrument design evaluation indices placed importance on learning, safety, motility and durability on top of usability and economic feasibility, which are the differences between the design evaluation indices of rehabilitation medical instrument and other product designs. The 10 rehabilitation medical device design evaluation indices and 44 sub-evaluation items were carried out in this study. This research is only on the overall rehabilitation medical device design evaluation indices. In future research, the evaluation indices will be applied in the actual rehabilitation medical design device through production of prototypes, while making revisions and supplementations where necessary.

Mammalian Reproduction and Pheromones (포유동물의 생식과 페로몬)

  • Lee, Sung-Ho
    • Development and Reproduction
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    • v.10 no.3
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    • pp.159-168
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    • 2006
  • Rodents and many other mammals have two chemosensory systems that mediate responses to pheromones, the main and accessory olfactory system, MOS and AOS, respectively. The chemosensory neurons associated with the MOS are located in the main olfactory epithelium, while those associated with the AOS are located in the vomeronasal organ(VNO). Pheromonal odorants access the lumen of the VNO via canals in the roof of the mouth, and are largely thought to be nonvolatile. The main pheromone receptor proteins consist of two superfamilies, V1Rs and V2Rs, that are structurally distinct and unrelated to the olfactory receptors expressed in the main olfactory epithelium. These two type of receptors are seven transmembrane domain G-protein coupled proteins(V1R with $G_{{\alpha}i2}$, V2R with $G_{0\;{\alpha}}$). V2Rs are co-expressed with nonclassical MHC Ib genes(M10 and other 8 M1 family proteins). Other important molecular component of VNO neuron is a TrpC2, a cation channel protein of transient receptor potential(TRP) family and thought to have a crucial role in signal transduction. There are four types of pheromones in mammalian chemical communication - primers, signalers, modulators and releasers. Responses to these chemosignals can vary substantially within and between individuals. This variability can stem from the modulating effects of steroid hormones and/or non-steroid factors such as neurotransmitters on olfactory processing. Such modulation frequently augments or facilitates the effects that prevailing social and environmental conditions have on the reproductive axis. The best example is the pregnancy block effect(Bruce effect), caused by testosterone-dependent major urinary proteins(MUPs) in male mouse urine. Intriguingly, mouse GnRH neurons receive pheromone signals from both odor and pheromone relays in the brain and may also receive common odor signals. Though it is quite controversial, recent studies reveal a complex interplay between reproduction and other functions in which GnRH neurons appear to integrate information from multiple sources and modulate a variety of brain functions.

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A Study for an Educational Direction in Fashion Design Subjected to Digital Environment I (디지털 환경에 따른 패션분야의 디자인 교육방향 연구 I)

  • 이미량
    • Archives of design research
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    • v.12 no.4
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    • pp.33-44
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    • 1999
  • Fashion is subjected to newness and change by itself. Fashion trend and tendency which could predict next season akeady indicated that digital and cybel11ation environment lliould be factors in fashion. Changes in future life styles and values caused by digital environment must be variables as fashion objects by themselves. Therefore digital environment of a fashion itself and that all encountered in fashion will not only be an existing situation but also an objective and a factor which must be pursued with fashionable sense in future fashion. Advanced technology and social change in relation to digital environment requires that educational method as well as its content will be changed on the scene of education for future. Thus we should seek an educational direction in fashion design for future society in which digital environment requires new paradigm. Subject to these backgrounds this study has an intension to study the change in fashion extensively influenced by expanded digital environment on a limited situational level of fashion design education and to suggest an educational direction for professional in future fashion design who will serve as a core of fashion area in the future. It is essential that education of professional in fashion for future should be achieved by digital-minded level that eagerly understands and accepts future society in which digital environment will be a main axis. It is necessary for this to make them expetience computers, digital media including CAD program. We have to note that education of digital media is more effective and applicable when accomplished in CAI level which can be related and expetienced with fashion education rather than mere functional training in media themselves. Intellectual creativity will be a vety source of producing values and national competence in 21st centtury. Education of design professional in fashion area must positively accept these environmental charactetistics in future society, as well as deeply reflect the education for the future.

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Mobility of pesticides in different slopes and soil collected from Ganwon alpine sloped-land under simulated rainfall conditions (실내 인공강우를 이용한 강원도 고랭지 토양의 토성 및 경사도별 농약 이동특성)

  • Kim, Seong-Soo;Kim, Tae-Han;Lee, Sang-Min;Park, Dong-Sik;Zhu, Yong-Zhe;Hur, Jang-Hyun
    • The Korean Journal of Pesticide Science
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    • v.9 no.4
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    • pp.316-329
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    • 2005
  • Mobility of pesticides can be occurred by run-off and leachate or soil erosion. It is one of the most important factors for environmental contamination, particularly in steep sloped-land as Gangwon alpine region. In this study, the mobility of seven pesticides in different slopes and soil textures was investigated by simulated rainfall under controlled conditions. Simulated rainfall subjected to 60 mm $hr^{-1}$ was treated using rainfall simulator after 12 hr of pesticide treatment. Amounts of the pesticides were measured in run-off and leachate samples. The soil samples collected after rainfall from upper and lower parts and three different depths of sloped-plot were also analyzed. At result, all pesticides from the un-off samples collected from Taebaek(silty clay loam) and Heongseong(sandy loam) soils were detected maximum 96% within 60 minutes after first collection except carbendazim and cypermethrin which have the lowest water solubilities. From the leachate samples, a similar pattern was shown as run-off samples but amount of pesticides was lower than those of run-off samples. In soil samples, the order of the amount of pesticide residues was $0{\sim}5$ > $5{\sim}10$ > $10{\sim}15$ cm of soil depth and no pattern was shown in upper and lower, and different slopes. Comparing to mobility of pesticides in water and soil samples, pesticides in soil samples were higher than those of water samples in Taebaek soil. However, the results using Heongseong soils were in contrast to those of Taebaek soil. These results revealed that mobility of pesticides can be dependant mainly on soil textures and physicochemical properties of pesticides. Therefore, it can be suggested that selection of pesticides should be considered for soil texture and properties of pesticide in the alpine and sloped-land.

Effect of Water Activity and Temperature on Growth, Germination, Sporulation, and Utilization of Carbon Source of Penicillium oxalicum (PENOX) as a Biocontrol Agent(BCA) for control of Clover(Trifolium repens L.) (토끼풀(Trifolium repens L.) 방제용 생물제제 Penicillium oxalicum (PENOX)의 발아, 생장, 포자생성 및 탄소원이용에 미치는 수분활성 및 온도의 영향)

  • Lee, Hyang-Burm;Kim, Chang-Jin
    • The Korean Journal of Pesticide Science
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    • v.4 no.3
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    • pp.68-74
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    • 2000
  • Penicillium oxalicum (PENOX) has shown the potential as a biocontrol agent(5CA) for control of a weed, clover(Trifolium repens L.) in grass plots. The bioherbicidal activity may be due to germinative and growth capacities and substrate availability of the agent over a range of environmental factors. The influences of different water activities($0.94{\sim}0.995\;a_w$) and temperatures($18{\sim}30^{\circ}C$) on mycelial growth, conidial germination, sporulation oil 2% MEA(malt extract agar) adjusted to different water activities with glycerol, and carbon source utilization using BIOLOG GN MicroPlate were determined in vitro. Decreases in $a_w$ on MEA caused a reduction in mycelial growth and conidial germination depending on temperature. The mycelial growth of PENOX was greatest at $30^{\circ}C/0.995\;a_w$. At some lowered water activity($0.97\;a_w$), the growth was similar between 25 and $30^{\circ}C$, and considerably decreased at lowered temperature($20^{\circ}C$). The germination rate was also greatest at $30^{\circ}C/0.995\;a_w$. Lag phase times for PENOX at $18^{\circ}C$ on MEA were >6hrs at tile whole $a_w$ level tested, and at 18 and $25^{\circ}C$ they were >18hrs and >12hrs at $0.94\;a_w$, respectively. However, its sporulation was some better at $0.97\;a_w$ than $0.995\;a_w$ or $0.94\;a_w$, and better at $20^{\circ}C$ than $30^{\circ}C$. In contrast, the number of carbon sources(niche size) utilized by PENOX varied with $a_w$ and temperature. Under some water stress condition($0.95\;a_w$), the agent utilized smaller number of carbon sources than $0.995\;a_w$ depending on temperature. The niche size at 0.995 and $0.95\;a_w$ were highest at $25^{\circ}C$, and showed 86 and 65, respectively. At $30^{\circ}C$, the niche size at 0.995 and $0.95\;a_w$ showed 84 and 50, respectively. There was no carbon source utilized by PENOX at $0.90\;a_w$ regardless of temperature. These information of tile fungal ecophysiology will be useful for the effective development of BCA.

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