• 제목/요약/키워드: Monoculture

검색결과 88건 처리시간 0.02초

유산균과 그 발효유가 Asperigllus parasiticus의 생육과 Aflatoxin 생성에 미치는 영향 (Effect of Lactobacillus casei and a Fermented Milk on the Growth and Aflatoxin Production of Asperillus Parasiticus)

  • 김종규;이용욱
    • 한국식품위생안전성학회지
    • /
    • 제13권2호
    • /
    • pp.164-170
    • /
    • 1998
  • 발효식품이 유해곰팡이에 의한 발암물질(aflatoxin)생성에 미치는 억제 효과에 관한 연구의 일환으로 유산균 및 유산균 발효유가 Asperillus Parasiticus ATCC 15517의 성장과 aflatoxin 생성에 미치는 영향을 실험하였다. 발효유를 일정 농도별로 첨가한 YES 배지에서 Asperillus Parasiticus를 배양말기에 대조군에 비하여 건조 균체량, 배양물의 pH, 그리고 alftoxin 생성량 등이 낮게 나타났다(p<0.05). Aflatoxin B1은 48.6~58.1% 각 감소되었으며 G1은 29.8~34.2%가 감소되었다. 이 발효유의 발효에 사용된 유산간균(lactobacillus casei)과 Asperillus Parasiticus를 변형 APT 배지에 혼합 배양한 결과 Asperillus Parasiticus 단독 배양의 경우에 비하여 균체량이 배양 5일째까지는 현저하게 억제되었으나 배양 말기에는 유의한 차이를 보이지 않았다. 또한 배양 말기에 단독 배양의 경우보다 pH가 훨씬 감소되고 (p<0.05) aflatoxin의 생성량도 감소되었다. 이로부터 발효유는 유해곰팡이인 Asperillus Parasiticus의 성장과 aflatoxin 생성을 억제시키는 효과를 가짐을 알 수 있으며, 이는 발효에 관여한 미생물의 경쟁뿐만 뿐만아니라 유산균의 대사산물에 의한 영향으로 보여진다.

  • PDF

청보리-옥수수 작부체계시 조사료 최대생산을 위한 청보리 수확시기 구명 (Study on High Forage Production in Double Cropping Systems with Barley and Corn at paddy field in Middle Region)

  • 주정일;강영식;성열규;지희정;이희봉
    • 한국초지조사료학회지
    • /
    • 제32권3호
    • /
    • pp.285-292
    • /
    • 2012
  • 논에서 청보리를 수확한 후 사료용 옥수수를 뒷그루로 재배할 경우 옥수수의 파종 시기는 청보리의 수확시기에 의하여 결정되고, 이에 따라 조사료 생산량이 영향을 받게 된다. 본 시험은 청보리를 생육단계별로 수확한 후 뒷그루로 사료용 옥수수를 파종하는 작부체계에서 조사료 생산성이 최대가 되는 청보리 수확시기와 사일리지 옥수수 파종시기를 구명코자 2009~2010년 충남농업기술원 논 시험포장에서 수행하였다. 청보리는 출수 후 20일에 수확하는 것이 생초수량이 가장 높았으나 건물수량과 TDN 수량은 황숙기에 수확(출수 후 25일경)하는 것이 가장 높았다. 옥수수는 청보리를 출수 25일에 수확한 후 파종하면 건물수량이 적기 파종에 비하여 약 16% 감소하였다. 옥수수 적기 파종에 의한 단작 재배는 청보리 출수 후 25일수확+ 옥수수 파종 작부조합에 비하여 총 생초수량 31%, 총 건물수량 28%, 총 TDN 수량 23% 감소되었다. "청보리+옥수수" 작부조합에서 총 생초수량은 '청보리 출수 후 15일 수확 ${\rightarrow}$ 옥수수 파종'이 가장 높았으나, 총 건물 수량과 TDN 수량은 "청보리 출수 후 25일 수확${\rightarrow}$사일리지 옥수수 파종"이 가장 높았으며, 이 때 청보리 생육단계는 황숙기이었고, 수분함량이 사일리지 제조에 가장 알맞은 시기이었다. 청보리를 황숙기 이후에 수확하면 옥수수의 수량이 급격히 감소되어 조사료의 총 생초수량과 TDN 수량이 크게 감소되므로 청보리를 황숙기 이전에 수확하고 옥수수를 가급적 빨리 파종할 필요가 있다.

유기농업단지 주요경관요소의 경관형용사 특성에 관한 연구 (A Study on the Landscape adjective characteristics for the Major Landscape Elements in Organic farming)

  • 안필균;엄성준;김남춘;김상범
    • 한국환경복원기술학회지
    • /
    • 제23권4호
    • /
    • pp.69-84
    • /
    • 2020
  • Up to date, the majority research on the major landscape elements in organic farming has been mainly focused on the practice of seeking efficiency. The problem is that this type of study contributes to polluting the agricultural environment and damaging the ecological circulation system. As an alternative, there is a growing body of research on organic farming, but it is not widely applied that research on how to manage the landscape considering the scenic characteristics of farming villages practicing organic farming. Hence, in this paper we utilized landscape adjectives as a way to enhance the objectivity of the organic agricultural complex landscape assessment. More specifically, not only this study used a landscape image of an organic agricultural complex to identify a landscape adjective suitable for the landscape elements but also this study confirmed the suitability of landscape adjectives comparing to the opinions of experts and the public. To carry out, this study performed the experts survey which is composed of 12 major landscape elements, including rice paddies and fields, monoculture and diverse crops, dirt roads, windbreak trees, accent planting, dum-bung(small pond), natural small river, natural waterways, plastic film houses, one-storied houses, and pavilion. As a result of deriving the landscape adjectives from the main landscape elements, there were nine landscape adjectives that were consistent with experts and the public, including "clear" and "Artless" for rice paddies and fields, while the mismatched landscape adjectives were 'traditional'. The accent planting was a combination of landscape adjectives such as 'natural' and 'clear', while the windbreak trees was a consensus of all landscape adjectives. Only two adjectives, 'friendly' and 'wild', agreed on the dirt load, nine dum-bung(small pond), ten natural small river, nine duckery, eight one-storied houses, 10 pavilion, eight monoculture and diverse crops, and three natural waterways. The most common landscape adjectives were windbreak trees, pavilions, and natural small river, all 10 landscape adjectives. However, it is considered that only three of the 10 landscape types on the dirt road and the natural number are matched. Thus, additional management measures will be needed. In addition, it was analyzed that the most common landscape adjectives were "Artless" and "friendly" 13 times. The landscape adjectives of the organic farming complex responded by experts were analyzed to be suitable for natural, clear, zingy, silent, traditional, artless, friendly, wild and Leisurely, and consistent with the general public's opinion.

The Effect of Mixed Cultivation Using Companion Plants on the Growth and Quality of Cherry Tomatoes

  • Lee, Byoung-Kwon;Yun, Hyung Kwon;Hong, In-Kyoung;Jung, Young-Bin;Lee, Sang-Mi
    • 인간식물환경학회지
    • /
    • 제24권4호
    • /
    • pp.311-327
    • /
    • 2021
  • Background and objective: Recent urban agriculture meets the needs of urban residents that safety and avoids using chemical pesticides. This study was conducted to identify various factors of companion planting affecting the growth of cherry tomatoes, which will promoting urban agriculture by improving socioeconomic satisfaction with gardening activities through quality. Methods: Four types of companion plants such as marigold, zinnia, spearmint and basil, that have a companion effect with growth, sugar content, and vitamin C content. We obtained the mean and standard deviation and tested the significance at a 95% confidence level (p < .05) with Duncan's multiple range test after one way ANOVA and MANOVA. Results: Compared to monoculture of cherry tomatoes, the plant growth in the treatment plots with companion planting showed a significant increase overall(p < .05), but there wasn't interaction effect among companion plants, planting ratio and type. As for the absorption of inorganic components, the companion planting showed better absorption than monoculture of cherry tomatoes, as favorable growth, and there was an interaction effect among the individual factors. The sugar content was higher than the standard sugar content of 5.8 brix in both the treatment plots at the control, and vitamin C content was higher than the control at 26.27mg/100g in all treatment plots, but there wasn't statistically significant difference. The soil pH in the cultivation plot ranges from 5.5 to 9.0 and was weakly alkaline in all treatment plots except zinnia, showing low contents of phosphoric acid, exchageable potassium, calcium and magnesium. Conclusion: This study was conducted to analyze various factors such as the growth of cherry tomatoes, contents of inorganic components, sugar content and vitamin C content of fruits, and soil analysis according to companion plants, planting type, and planting ratio. We will study sugar content by measuring the change in growth every phase of fruits.

Microbe-Based Plant Defense with a Novel Conprimycin Producing Streptomyces Species

  • Kwak, Youn-Sig
    • 한국균학회소식:학술대회논문집
    • /
    • 한국균학회 2015년도 춘계학술대회 및 임시총회
    • /
    • pp.54-54
    • /
    • 2015
  • Crops lack genetic resistance to most necrotrophic soil-borne pathogens and parasitic nematodes that are ubiquitous in agroecosystems worldwide. To overcome this disadvantage, plants recruit and nurture specific group of antagonistic microorganisms from the soil microbiome to defend their roots against pathogens and other pests. The best example of this microbe-based defense of roots is observed in disease-suppressive soils in which the suppressiveness is induced by continuously growing crops that are susceptible to a pathogen. Suppressive soils occur globally yet the microbial basis of most is still poorly described. Fusarium wilt, caused by Fusarium oxysporum f. sp. fragariae is a major disease of strawberry and is naturally suppressed in Korean fields that have undergone continuous strawberry monoculture. Here we show that members of the genus Streptomyces are the specific bacterial components of the microbiome responsible for the suppressiveness that controls Fusarium wilt of strawberry. Furthermore, genome sequencing revealed that Streptomyces griseus, which produces a novel thiopetide antibiotic, is the principal species involved in the suppressiveness. Finally, chemical-genetic studies demonstrated that S. griseus antagonizes F. oxysporum by interfering with fungal cell wall synthesis. An attack by F. oxysporum initiates a defensive "cry for help" by strawberry root and the mustering of microbial defenses led by Streptomyces. These results provide a model for future studies to elucidate the basis of microbially-based defense systems and soil suppressiveness from the field to the molecular level.

  • PDF

Influence of Light on Biomass of Soybean in Narrow Strip Cropping of Oat, Corn, and Soybean

  • Van, Kyujung
    • 한국작물학회지
    • /
    • 제47권5호
    • /
    • pp.368-373
    • /
    • 2002
  • The strip intercropping system has used due to many advantages. Many researches supported these crop systems are usually equal to or better than monoculture crop systems in both total production and profit. There was no research to examine the important ecological factors in the competition between crops. A strip intercropping system composed of adjacent narrow strips of corn, soybean, and oat/legumes has been investigated in Iowa, USA. This study conducted to investigate why and how the differences in soybean yield are produced and affected by light, one of the microclimate, of the strip intercropping system. In height, the two rows of soybean closest to corn were taller than the two rows near the then-empty oat strip. The height of each crop decreased as the amount of light received increased. Weight of plant parts was lowest in row 1, nearest corn, and highest in row 4, next to the vacant oat strip. Daily photon flux density(PFD) increased with increasing distance from corn, with the highest value occurring on the edge next to the empty oat strip. Analyses of the relationship between light and biomass of soybean showed that all biomass measurements had a positive relationship to total PFD per day except height.

Silage용 옥수수와 두과작물의 간작에 관한 연구 I. Silage용 옥수수 ( Zea mays L. ) 동부 ( Vigna sinensis King ) 의 간작이 생육특성과 건물 및 유기물수량에 미치는 영향 (Studies on Corn-Legume Intercropping System I. Growth charateristics, dry matter and organic matter yield of corn (Zea mays L.)-cowpea (Vigna sinensis King) intercropping)

  • 이성규
    • 한국초지조사료학회지
    • /
    • 제8권1호
    • /
    • pp.47-54
    • /
    • 1988
  • The growth characteristics and yield per unit area of two cultivation systems of forage, corn (Zea mays L.) monoculture and corn-cowpea (Vigna sinesis King) inter-cropping were compared and obtained follow results. 1. The two cultivation systems were not significantly different in leaf length, leaf width and length of internode with harvesting time. 2. The weight of stalk and leaves of a plant were decreased with maturity, while weight of ear was markedly increased. The patterns of relative ratio of each components was essentially same in each cultivation system. In corn monocrop., the percentages of stalk, leaf and ear at final harvesting stage were 22.9, 13.7 and 63.4, respectively. 3. Dry matter yield per unit area (33kgIlOa) of intercropped corn at yellow stage was similar to that of monocropped corn ( l,482.8kg/ 10a vs 1 ,SO8.9kg/ 10a). At ripe stage, however, the DM yield of intercrop. was higher than that of monocrop. (1,810.4kg/lOa vs 1,660.4 kg/ 1 Oa). 4. The same pattern was observed in organic matter yield.

  • PDF

밀기울 첨가수준이 알팔파 Silage 품질에 미치는 영향 (Effects of Quality of Alfalfa Silage by Different Wheat Bran Mixing Levels)

  • 신재순;차영호;이혁호;김정갑;진현주;정기영
    • 한국초지조사료학회지
    • /
    • 제16권3호
    • /
    • pp.225-229
    • /
    • 1996
  • To find out the optimum mixing level of wheat bran to improve the quality of 1st cut Alfalfa silage, this trial was canied out at two-year's Alfalfa monoculture field of the National Livestock Research Institute, Suwon, Korea, from May 1955 to Oct. 1995. The results are as follows. I. According to the increase of wheat bran mixing level, DM content was high from 23.19%(nil) to 35.70%(40% mixing), pH of silage were low from 5.51(nil) to 4.45(40% mixing). but there were not significant at 20% mixing or more(P>0.05). 2. Also it was appeared to the same trend at Lactic acid content and in the Flieg's score of silage it was highest as 59 in the 20% mixing level. 3. In chemical component of silages there were not significant at 20% mixing or more in crude protein, crude fiber and ashes content, 30% mixing or more in ether extract and 10% or less in NFE content(P>0.05). 4. TDN, NEL and StE contents were low as adding level was increased. respectively, but there were not significant(P>O.OS). As mentioned above the results, desirable mixing level of wheat bran to lstcut Alfalfa to improve the quality of silage was 20% of fresh weight.

  • PDF

Korean University Students' Progress in Developing Social Interaction with Native Speakers in the UK

  • Back, Ju-Hyun
    • 영어어문교육
    • /
    • 제15권3호
    • /
    • pp.1-31
    • /
    • 2009
  • Although Korean university students' primary concern is academic success in their higher degrees in the UK, they highly desire to develop English communicative competence through a number of opportunities to speak with natives speakers. The paper aims at examining to what extent they are able to be socialised into a new environment while they are studying at UK universities. The in-depth, longitudinal interviews with the targeted group of six Korean masters' students at the University of York was undertaken to observe the pace of their progress in developing social skills. Reluctance and hesitance to contact and interact with their supervisors and other academic staff persisted for most of them to the final term caused by cultural reasons such as face and hierarchy rather than language problems. Despite the six participants' variation in their patterns of social interaction, they struggled with pressures towards monoculture-biased interaction with Korean people, which was quite extreme for the five participants. This passivity can be explained by several reasons such as the students' lack of communicative competence and other situational factors on one-year course. It is important to note that students' failure to develop network with native speakers is strongly associated with experience of cultural withdrawal and frustration with developing communicative competence in English.

  • PDF

Low algal diversity systems are a promising method for biodiesel production in wastewater fed open reactors

  • Bhattacharjee, Meenakshi;Siemann, Evan
    • ALGAE
    • /
    • 제30권1호
    • /
    • pp.67-79
    • /
    • 2015
  • Planktivorous fish which limit zooplankton grazing have been predicted to increase algal biodiesel production in wastewater fed open reactors. In addition, tanks with higher algal diversity have been predicted to be more stable, more productive, and to more fully remove nutrients from wastewater. To test these predictions, we conducted a 14-week experiment in Houston, TX using twelve 2,270-L open tanks continuously supplied with wastewater. Tanks received algal composition (monocultures or diverse assemblage) and trophic (fish or no fish) treatments in a full-factorial design. Monocultures produced more algal and fatty acid methyl ester (FAME) mass than diverse tanks. More than 80% of lipids were converted to FAME indicating potentially high production for conversion to biodiesel (up to $0.9T\;ha^{-1}y^{-1}$). Prolific algal growth lowered temperature and levels of total dissolved solids in the tanks and increased pH and dissolved oxygen compared to supply water. Algae in the tanks removed 91% of nitrate-N and 53% of phosphorus from wastewater. Monocultures were not invaded by other algal species. Fish did not affect any variables. Our results indicated that algae can be grown in open tank bioreactors using wastewater as a nutrient source. The stable productivity of monocultures suggests that this may be a viable production method to procure algal biomass for biodiesel production.