• Title/Summary/Keyword: damage plastic

Search Result 814, Processing Time 0.026 seconds

Studies on the Patterns of Plastic Film House, Their Growing; Conditions, and Diseases and Pests Occurrence on Horticultural Crops in Southern Part of Korea. Insects and Nematodes Associated with Horticultural Crops and Effect of Nursery Soil Conditions on the Infection of Root-knot Nematode (남부지방(南部地方) 시설원예(施設園藝)의 유형(類型).재배환경(栽培環境) 및 병해충발생(病害蟲發生)에 관(關)한 연구(硏究) -충발생양상(蟲發集樣相)과 상토(床土)의 선택(選擇)에 따른 뿌리혹선충(線蟲)의 발생(發生)-)

  • Choo, Ho-Yul;Kim, Hee-Kyu;Park, Jung-Choon;Lee, Sang-Myeong;Lee, Jeong-Im
    • Korean journal of applied entomology
    • /
    • v.26 no.4 s.73
    • /
    • pp.195-201
    • /
    • 1987
  • Insects and nematodes associated with crops growing in plastic film houses were surveyed throughout the southern part of Korea at Jinju, Jiphyeon, Geumsan, Hapcheon, Changyeong, Namji, Milyang, Kimhae, Busan, Sooncheon and Gwangyang from December of 1984 to December of 1985. The phytonematodes representing six families, nine genera and nine species, and the insects representing four orders, seventeen families, twenty-three genera and twenty-four species were identified. The mite also caused problem on the leaves of strawberry and watermelon. Of these Meloidogyne incognita and Aphis gossyphii were most important ones. Aphelenchoides fragariae and M. hapla, however dominant nematodes on strawberry. M. incognita was always detected from pepper plants which were heavily infected with Phytophthora capsici. Tomato roots were readily infected with root-knot nematodes in non-sterilized upland surface soil. However, tomato were growing-vigorouly free from nematode damage in the upland surface soil treated by nematicide or in the paddy soil. A few galls were developed even in the upland subsoil at 60cm below surface. Soil salinity affected profoundly the host-root-knot nematode interaction: the numerous galls were developed on the tomato roots at EC $1mS/cm^2$ followed by 4mS and 2mS, but few galls were at 6mS.

  • PDF

Soil Chemical Characteristics and Comparison with Infested Status of Nematode(Meloidogyne spp.) in Plastic House Continuously Cultivated Oriental Melon in Songju (성주 지역 시설참외 연작지의 토양특성 및 토양선충 변화)

  • Jun, Han-Sik;Park, Woo-chul
    • Korean Journal of Environmental Agriculture
    • /
    • v.20 no.2
    • /
    • pp.127-132
    • /
    • 2001
  • This study was conducted for ten years to evaluate the effective soil management for preventing the infection of root-knot nematode in the field of continuous cultivation with oriental melon under plastic house in Songju area of kyongbuk province. The content of available phosphate, total nitrogen, organic matter, CEC, and exchangeable base in the soil increased with the increase of continuous cultivation year. Especially salt content in the soil increased form 1.2 to 4.55 mS/cm and the yield of oriental melon dramatically decreased with the continuous cultivation year. The number of root-knot nematode was 91 per $300\;cm^3$ of soil in the field of continuous cultivation for 3 years and showed slight damage on the oriental melon, but it was 518 in the field of $4{\sim}6$ years continuous cultivation and showed that 50% of plants died in August, and the yield of late season was less than 50% compared to normal plant. For the seasonal changes in infection rate of root-knot nematode on oriental melon plant, 15% of the normal plant was infected by nematode in February and increased gradually by $10{\sim}20%$ per month, 60% of plants was infected in July. The density of root-knot nematode nymph was 167 in February and increased to 1,625 in August. The infection rate of nematode was 35%, and the number of nematode was about 54 in nursery soil originated from paddy soil, upland soil, and river sand. There were no relationship between the number of nematode and available phosphate or exchangeable base in the soil of plastichouse where oriental melon plants were grown.

  • PDF

EFFECT OF NERVE GROWTH FACTOR GENE INJECTION ON THE NERVE REGENERATION IN RAT LINGUAL NERVE CRUSH-INJURY MODEL (백서 설신경 압박손상모델에서 신경성장인자 유전자 주입이 신경재생에 미치는 영향)

  • Gao, En-Feng;Chung, Hun-Jong;Ahn, Kang-Min;Kim, Soung-Min;Kim, Yun-Hee;Jahng, Jeong-Won;Lee, Jong-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.28 no.5
    • /
    • pp.375-395
    • /
    • 2006
  • Purpose: Lingual nerve (LN) damage may be caused by either tumor resection or injury such as wisdom tooth extraction, Although autologous nerve graft is sometimes used to repair the damaged nerve, it has the disadvantage of necessity of another operation for nerve harvesting. Moreover, the results of nerve grafting is not satisfactory. The nerve growth factor (NGF) is well-known to play a critical role in peripheral nerve regeneration and its local delivery to the injured nerve has been continuously tried to enhance nerve regeneration. However, its application has limitations like repeated administration due to short half life of 30 minutes and an in vivo delivery model must allow for direct and local delivery. The aim of this study was to construct a well-functioning $rhNGF-{\beta}$ adenovirus for the ultimate development of improved method to promote peripheral nerve regeneration with enhanced and extended secretion of hNGF from the injured nerve by injecting $rhNGF-{\beta}$ gene directly into crush-injured LN in rat model. Materials and Methods: $hNGF-{\beta}$ gene was prepared from fetal brain cDNA library and cloned into E1/E3 deleted adenoviral vector which contains green fluorescence protein (GFP) gene as a reporter. After large scale production and purification of $rhNGF-{\beta}$ adenovirus, transfection efficiency and its expression at various cells (primary cultured Schwann cells, HEK293 cells, Schwann cell lines, NIH3T3 and CRH cells) were evaluated by fluorescent microscopy, RT-PCR, ELISA, immunocytochemistry. Furthermore, the function of rhNGF-beta, which was secreted from various cells infected with $rhNGF-{\beta}$ adenovirus, was evaluated using neuritogenesis of PC-12 cells. For in vivo evaluation of efficacy of $rhNGF-{\beta}$ adenovirus, the LNs of 8-week old rats were exposed and crush-injured with a small hemostat for 10 seconds. After the injury, $rhNGF-{\beta}$ adenovirus($2{\mu}l,\;1.5{\times}10^{11}pfu$) or saline was administered into the crushed site in the experimental (n=24) and the control group (n=24), respectively. Sham operation of another group of rats (n=9) was performed without administration of either saline or adenovirus. The taste recovery and the change of fungiform papilla were studied at 1, 2, 3 and 4 weeks. Each of the 6 animals was tested with different solutions (0.1M NaCl, 0.1M sucrose, 0.01M QHCl, or 0.01M HCl) by two-bottle test paradigm and the number of papilla was counted using SEM picture of tongue dorsum. LN was explored at the same interval as taste study and evaluated electro-physiologically (peak voltage and nerve conduction velocity) and histomorphometrically (axon count, myelin thickness). Results: The recombinant adenovirus vector carrying $rhNGF-{\beta}$ was constructed and confirmed by restriction endonuclease analysis and DNA sequence analysis. GFP expression was observed in 90% of $rhNGF-{\beta}$ adenovirus infected cells compared with uninfected cells. Total mRNA isolated from $rhNGF-{\beta}$ adenovirus infected cells showed strong RT-PCR band, however uninfected or LacZ recombinant adenovirus infected cells did not. NGF quantification by ELISA showed a maximal release of $18865.4{\pm}310.9pg/ml$ NGF at the 4th day and stably continued till 14 days by $rhNGF-{\beta}$ adenovirus infected Schwann cells. PC-12 cells exposed to media with $rhNGF-{\beta}$ adenovirus infected Schwann cell revealed at the same level of neurite-extension as the commercial NGF did. $rhNGF-{\beta}$ adenovirus injected experimental groups in comparison to the control group exhibited different taste preference ratio. Salty, sweet and sour taste preference ratio were significantly different after 2 weeks from the beginning of the experiment, which were similar to the sham group, but not to the control group.

Superoxide Dismutase Gene Expression Induced by Lipopolysaccharide in Alveolar Macrophage of Rat (폐포대식세포에서 내독소 자극에 의한 Superoxide Dismutase 유전자발현의 조절 기전)

  • Park, Kye-Young;Yoo, Chul-Gyu;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo;Hyun, In-Gyu
    • Tuberculosis and Respiratory Diseases
    • /
    • v.42 no.4
    • /
    • pp.522-534
    • /
    • 1995
  • Background: In the pathogenesis of acute lung injury induced by lipopolysaccharide(LPS), oxygen radiclls are known to be involved in one part. Superoxide dismutase(SOD) protects oxygen radical-induced tissue damage by dismutating superoxide to hydrogen peroxide. In eukaryotic cells, two forms of SOD exist intracellularly as a cytosolic, dimeric copper/zinc-containing SOD(CuZnSOD) and a mitochondrial, tetrameric manganese-containing SOD(MnSOD). But there has been little information about SOD gene expression and its regulation in pulmonary alveolar macrophages(PAMs). The objective of this study is to evaluate the SOD gene expression induced by LPS and its regulation in PAMs of rat. Method: In Sprague-Dawley rats, PAMs obtained by broncholaveolar lavage were purified by adherence to plastic plate. To study the effect of LPS on the SOD gene expression of PAMs, they were stimulated with different doses of LPS($0.01{\mu}g/ml{\sim}10{\mu}g/ml$) and for different intervals(0, 2, 4, 8, 24hrs). Also for evaluating the level of SOD gene regulation actinomycin D(AD) or cycloheximide(CHX) were added respectively. To assess whether LPS altered SOD mRNA stability, the rate of mRNA decay was determined in control group and LPS-treated group. Total cellular RNA extraction by guanidinium thiocyanate/phenolfchlorofonn method and Northern blot analysis by using a $^{32}P$-labelled rat MnSOD and CuZnSOD cDNAs were performed. Results: The expression of mRNA in MnSOD increased dose-dependently, but not in CuZnSOD. MnSOD mRNA expression peaked at 8 hours after LPS treatment. Upregulation of MnSOD mRNA expression induced by LPS was suppressed by adding AD or CHX respectively. MnSOD mRNA stability was not altered by LPS. Conclusion: These findings show that PAMs of rat could be an important source of SOD in response to LPS, and suggest that their MnSOD mRNA expression may be regulated transcriptionally and require de novo protein synthesis without affecting mRNA stability.

  • PDF

Characteristics of Rooting and Community Maintenance of Some Gramineae planted on Urban Stream Bank Slope (도시하천 제방사면에 식재한 몇몇 벼과식물의 활착 및 군락유지 특성)

  • Yang, Hong-Mo
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.45 no.5
    • /
    • pp.42-59
    • /
    • 2017
  • To investigate rooting and community forming ability, sod strips of Gramineae such as Miscanthus sacchariflorus (Maxim.) Benth., Miscanthus sinensis var. purpurascens(Andersson) Rendle, Imperata cylindrica var. koenigii(Retz.) Pilg., and Arundinella hirta(Thunb.) Tanaka were planted horizontally at a width of 10~15cm in October 2010 on the bank slope of Kwangju Stream in Korea. Seeds of each species were sown in April 2010 in plastic seedbeds(60cm length ${\times}$ 30cm width ${\times}$ 5cm depth) filled with 4cm of garden soil and grew until October 2010 to form rectangular sod, which then was cut into multiple strips(20cm length ${\times}$ 6cm width ${\times}$ 4cm root depth). Weeds growing on the experiment sites were removed twice a year until those four species had formed a community by 2013. Weeds were not eradicated during 2014 and 2015 to observe whether the community formation can be maintained without weed removal. t-tests on stem numbers and heights in May, July, and September were conducted between 2013 and 2014, and between 2014 and 2015. Stem numbers and heights of the four species in 2014 were significantly decreased(p<0.001) compared with those in 2013 due to weed damage to their growth in 2014. Stem numbers and heights of Miscanthus sacchariflorus(Maxim.) Benth., Miscanthus sinensis var. purpurascens(Andersson) Rendle, Imperata cylindrica var. koenigii(Retz.) Pilg. in 2015 were similar to those in 2014(p>0.05). Stem numbers and heights of Arundinella hirta(Thunb.) Tanaka in 2015, however, were significantly reduced compared with those in 2014(p<0.001) due to weed impact on its growth. After three years of weed removal, a community of each species was formed. Miscanthus sacchariflorus(Maxim.) Benth., Miscanthus sinensis var. purpurascens(Andersson) Rendle, Imperata cylindrica var. koenigii(Retz.) Pilg. were able to establish communities without any further weed removal. Arundinella hirta(Thunb.) Tanaka, however, was not able to maintain its community due to considerable damage to its growth caused by weeds even after three years of weed removal. Miscanthus sacchariflorus(Maxim.) Benth., Miscanthus sinensis var. purpurascens(Andersson) Rendle, Imperata cylindrica var. koenigii(Retz.) Pilg. are more suitable to sod strip plantings on stream bank slopes in terms of the maintenance of community formation without weed eradication. t-test on stem numbers and heights each September during the five year experiment period between sod strip planting and potted plants of the four species were conducted. Stem numbers of strip sod plantings were significantly higher(p<0.001) than those of potted one. Heights of strip sod plantings, however, were significantly lower(p<0.05) than those of the potted samples. Therefore, strip sod planting is more advantageous regarding bank slope erosion protection due to the higher number of stems.

Changes of Yield and Quality in Potato (Solanum tuberosum L.) by Heat Treatment (폭염처리에 의한 감자의 수량성과 품질 변화)

  • Lee, Gyu-Bin;Choi, Jang-Gyu;Park, Young-Eun;Jung, Gun-Ho;Kwon, Do-Hee;Jo, Kwang-Ryong;Cheon, Chung-Gi;Chang, Dong Chil;Jin, Yong-Ik
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.24 no.3
    • /
    • pp.145-154
    • /
    • 2022
  • Due to abnormal weather conditions caused by climate change, natural disasters and damages are gradually increasing around the world. Global climate change as accompanied by warming is projected to exert adverse impact on production of potato, which is known as cool season crop. Even though, role of potato as a food security crop is expected to increase in the future, the climate change impacts on potato and adaption strategies are not sufficiently established. Therefore, this study was conducted to analyze the damage pattern of potatoes due to high temperature treatment and to evaluate the response of cultivars. T he high temperature treatment (35~38℃) induced heat stress by sealing the plastic house in midsummer (July), and the quantity and quality characteristics of potatoes were compared with the control group. T otal yield, marketable yield (>80 g) and the number of tubers per plants decreased when heat treatment was performed, and statistical significance was evident. In the heat treatment, 'Jayoung' cultivar suffered a high heat damage with an 84% reduction in yield of >80 g compared to the control group. However, in Jopung cultivar, the decrease was relatively small at 26%. Tuber physiological disturbances (Secondary growth, Tuber cracking, Malformation) tended to increase in the heat stress. Under heat conditions, the tubers were elongated overall, which means that the marketability of potatoes was lowered. T he tuber firmness and dry matter content tended to decrease significantly in the heat-treated group. T herefore, the yield and quality of tubers were damaged when growing potatoes in heat conditions. T he cultivar with high heat adaptability was 'Jopung'. T his result can be used as basic data for potato growers and breeding of heat-resistant cultivars.

Regional cooperation of NOWPAP MERRAC against marine litter from sea-based activities in the Northwest Pacific region (북서태평양 지역의 해상기인 해양쓰레기 저감을 위한 NOWPAP 방제지역활동센터의 지역협력 활동현황 분석 및 향후 발전방향)

  • Noh, Hyon-Jeong;Oh, Jeong-Hwan;Kang, Seong-Gil;Kang, Chang-Gu
    • Journal of the Korean Society for Marine Environment & Energy
    • /
    • v.11 no.3
    • /
    • pp.150-159
    • /
    • 2008
  • The marine litter generated as by-products of human activities and economic development enters to the sea through rivers or stream Indirectly, and through sea-based activities directly. It is commonly comprised of materials that degrade very slowly, such as various plastic products, polystyrene, glass, rubber, metal, wood, derelict fishing nets, wire, rope and so on. Such litter is found in the water column and on the seafloor as well as coastal areas In the Northwest Pacific region. It causes injury or death of human and other living organisms and also accident or damage of the vessel. It is not only a problem of country but also regional and/or global problem because it is transported by currents and winds from one country to another. In this regard, Northwest Pacific Action Plan (NOWPAP) Marine Litter Activity (MALITA) project had been carried out during 2006-2007 biennium and NOWPAP Regional Action Plan on Marine Litter (RAP MALI) has been also continuously implemented in the 2008-2009 biennium as next phase step of MALITA. MERRAC, one of four Regional Activity Centres (RACs) of NOWPAP, has developed monitoring guidelines, sectoral guidelines, and brochures related to sea-based marine litter and port reception facilities and services through MALITA project. Based upon these output, MERRAC will continuously implement relevant activities of RAP MALI in order to help to establish and improve a regional mechanism to deal with the sea-based marine litter problem. This paper aims to introduce MERRAC activities under MALITA and RAP MALI, and to suggest several recommendations to reduce marine litter in the NOWPAP region.

  • PDF

Assessment of Physiological Activity of Entomopathogenic Fungi with Insecticidal Activity Against Locusts (풀무치에 대하여 살충활성을 보유한 곤충병원성 진균의 생리활성 평가)

  • Lee, Mi Rong;Kim, Jong Cheol;Lee, Se Jin;Kim, Sihyeon;Lee, Seok Ju;Park, So Eun;Lee, Wang Hyu;Kim, Jae Su
    • Korean journal of applied entomology
    • /
    • v.56 no.3
    • /
    • pp.301-308
    • /
    • 2017
  • Locusts, Locusta migratoria (Orthoptera: Acrididae) are periodical unpredictable agricultural pests worldwide and cause serious damage to crop production; however, little consideration has been given to the management of this pest. Herein, we constructed a locust-pathogenic fungal library and confirmed that some fungi could be used as resources for locust management. First, the entomopathogenic fungi were collected from sampled soils using a Tenebrio molitor-based baiting system. For the locust assay, a locust colony was obtained from the National Institute of Agricultural Science and Technology. A total of 34 entomopathogenic fungal granules, which were produced by solid cultures, were placed in the plastic insect-rearing boxes (2 g/box) and nymphs of locust were contained in the box. In 3-7 days, mycosis was observed on the membranous cuticles of the head, abdomen, and legs of locusts. In particular, Metarhizium anisopliae, M. lepidiotae, and Clonostachys rogersoniana exhibited high virulence against the locust. Given that the 34 isolates could be used in field applications, their conidial production and stability (thermotolerance) were further characterized. In the thermotolerance assay, Paecilomyces and Purpureocillium isolates had higher thermotolerance than the other isolates. Most of the fungal isolates produced ca. >$1{\times}10^8conidia/g$ on millet grain medium. In a greenhouse trial, the granular application of M. anisopliae isolate on the soil surface resulted in 85.7% control efficacy. This work suggests that entomopathogenic fungi in a granular form can be effectively used to control the migratory locust.

Influence of Daytime Temperature on the Time Required for Fruit Harvest and Yield of Hot Pepper (주간온도가 고추의 수확 소요일수 및 수량에 미치는 영향)

  • Lee, Sang-Gyu;Choi, Chang-Sun;Lee, Jun-Gu;Jang, Yoon-Ah;Nam, Chun-Woo;Lee, Hee-Ju;Suh, Jeong-Min;Kang, Jum-Soon
    • Journal of Environmental Science International
    • /
    • v.22 no.9
    • /
    • pp.1181-1186
    • /
    • 2013
  • Due to climate change, the occurrence of abnormal weather conditions has become more frequent, causing damage to vegetable crops grown in Korea. Hot pepper, Chinese cabbage and radish, the three most popular vegetables in Korea, are produced more in the field than in the greenhouse. It has been a trend that the time for field transplanting of seedlings is getting earlier and earlier as the spring temperatures keep rising. Seedlings transplanted too early in the spring take a longer time to resume the normal growth, because they are exposed to suboptimal temperature conditions. This study examined the influence of air temperature during seedling growth on the time required to reach the first fruit maturity and yield of hot pepper. Seedling plants of 'Super Manita' hot pepper was grown in temperatures $2.5^{\circ}C$ and $5.0^{\circ}C$ lower than the optimum temperature (determined by the average of temperatures for the past 5 years). Seedlings were transplanted into round plastic containers (30-cm diam., 45-cm height) and were placed in growth chambers in which the ambient temperature was controlled under natural sunlight. The growth of seedlings under lowered temperatures was reduced compared to the control. The mineral (K, Mg, P, N) concentrations in the leaf tissues were higher when plants were grown with the ambient temperature $2.5^{\circ}C$ lower than the optimum, regardless of changes in other growth parameters. Tissue calcium (Ca) concentration was the highest in the plants grown with optimum temperature. The carbohydrate to nitrogen (C/N) ratio, which was the highest (18.3) in the plants grown with optimum temperature, decreased concomitantly as the ambient temperature was lowered $2.5^{\circ}C$ and $5.0^{\circ}C$. The yield of the early harvested fruits was also reduced as the ambient temperature became lower. The first fruit harvest date for the plants grown with optimum temperature (June 27) was 13 days and 40 days, respectively, earlier than that in plants grown with $2.5^{\circ}C$ (July 10) and $5.0^{\circ}C$ (Aug 6) lower ambient temperatures. The fruit yield per plant for the optimum temperature (724 g) was the greatest compared to those grown with $2.5^{\circ}C$ (446 g) and $5.0^{\circ}C$ (236 g) lower temperatures. The result of this study suggests that the growers should be cautioned not to transplant their hot pepper seedlings too early into the field, since it may delay the time of first harvest eventually reducing total fruit yield.

Uplift Bearing Capacity of Spiral Steel Peg for the Single Span Greenhouse (온실용 나선철항의 인발저항력 검토)

  • Lee, Bong Guk;Yun, Sung Wook;Choi, Man Kwon;Lee, Si Young;Moon, Sung Dong;Yu, Chan;Yoon, Yong Cheol
    • Journal of Bio-Environment Control
    • /
    • v.23 no.2
    • /
    • pp.109-115
    • /
    • 2014
  • This study examined the uplift bearing capacity of spiral steel pegs according to the degree of soil compaction and embedded depth in a small-scaled lab test. As a result, their uplift bearing capacity increased according to the degree of soil compaction and embedded depth. The uplift bearing capacity under the ground condition of 85% compaction rate especially recorded 48.9 kgf, 57.9 kgf, 86.2 kgf and 116.6 kgf at embedded depth of 25 cm, 30 cm, 35 cm and 40 cm, respectively, being considerably higher than under other ground conditions. There were huge differences in the uplift bearing capacity of spiral steel pegs according to the compaction conditions of ground. Their maximum uplift bearing capacity was 116.6 kgf under the ground condition of 85% compaction rate and at embedded depth of 40 cm, and it is very high considering the data of spiral steel pegs. It is thus estimated that wind damage can be effectively reduced by careful maintenance of ground condition surrounding spiral steel pegs. In addition, spiral steel pegs will be able to make a contribution to greenhouse structural stability if proper installation methods are provided including the number and interval according to the types of greenhouse as well as fixation of plastic film. The findings of the study indicate that the optimal effects of spiral steel pegs for greenhouse can be achieved at embedded depth of more than 35cm and compaction degree of more than 85%. The relative density of the model ground in the test was 67% at compaction rate of 85%.