• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.05a
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• pp.27-32
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• 1998

국내에 보급되어 있는 유리온실은 네덜란드에서 수입된 벤로형(Venlo type or Dutchlite)과 벤로형에 비해서 동고가 높으며 온실 한 동의 폭이 상대적으로 큰 광폭형(widespan type)이 대부분을 차지하고 있다. 벤로형 은실의 측고는 3.5~4.0m로서 다소 차이가 있으나, 한 동의 폭과 지붕경사면의 길이가 일정하기 때문에 온실의 지붕경사각은 대부분 22$^{\circ}$를 나타낸다. (중략)

• Korean Journal of Medicinal Crop Science
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• v.27 no.6
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• pp.404-411
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• 2019

Background: In September 2017, wilting and rhizome rot symptoms were observed on Atractylodes macrocephala Koidz. in Jecheon-si and Eumseong-gun. This study was carried out to isolate hitherto unidentified pathogenic fungi from A. macrocephala and to test the pathogenicity of isolated fungi against Atractylodes spp. genus such as A. macrocephala, A. japonica, and their interspecific hybrids. Methods and Results: The diseased plants were washed with running tap water, and the boundary between the healthy area and the diseased area was cut while the pathogens were isolated by growing cultures from the diseased areas on Phytophthora semi-selective medium. The internal transcribed spacer (ITS) region of the isolates was used in this study for identification. Test plants were cultivated in the glasshouse at 20℃ - 30℃ for 4 months and then used for pathogenicity test. The pots with plants inoculated with mycelial plugs and zoospores were placed at 25℃ for 48 h in a dew chamber where relative humidity was above 95%, and then moved into the glasshouse at 20℃ - 30℃. The presence or absence of pathogenicity of the strains was determined by evaluating the symptom of plant wilting. The inoculation test was performed in three replicates with a non-treated control. Conclusions: On the basis of results of ITS sequence analysis, the strains isolated from the diseased plants was identified as Phytophthora sansomeana. Biological assay using test plants confirmed the pathogenicity of P. sansomeana against Atractylodes macrocephala. This is the first report of rhizome rot in A. macrocephala caused by P. sansomeana.

• Journal of Microbiology and Biotechnology
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• v.17 no.12
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• pp.2071-2075
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• 2007

Fourteen Bacillus thuringiensis isolates having both insecticidal activity and in vitro antifungal activity were selected and tested for in vivo antifungal activity against tomato late blight, wheat leaf rust, tomato gray mold, and barley powdery mildew in growth chambers. All the isolates represented more than 70% disease control efficacy against at least one of four plant diseases. Specifically, 12 isolates exhibited strong control activity against barley powdery mildew. Under glasshouse conditions, four (50-02, 52-08, 52-16, and 52-18) of the isolates also displayed potent control efficacy against cucumber powdery mildew. To our knowledge, this is the first report of B. thuringiensis isolates that have disease control efficacy against powdery mildew of barley and cucumber as well as insecticidal activity.

• Mycobiology
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• v.28 no.4
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• pp.180-184
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• 2000

In order to find an environment-friendly method to suppress astragal stem rot caused by the isolates of Rhizoctonia solani AG 1 and AG 4, we tested an antagonistic fungus Gliocladium virens G1 was evaluated as a biocontrol agent and estimated inorganic compounds and organic materials were tested for their effect of the disease suppression. G. virens G1 effectively inhibited mycelial growth in a dual culture and caused mycelial lysis in the culture filtrate. No adverse effect was observed when examined for seed germination and seedling growth. Promoted seedling growth was observed with the seed treatment. Seeds of astragal plant were germinated higher in the sterile soil than the natural soil. Of 14 inorganics tested, alum, aluminum sulfate and calcium oxide significantly suppressed the mycelial growth and sclerotial germination. Milled pine bark and oak sawdust also suppressed the mycelial growth. Soil amended with 1% of G. virens G1 composted with pine bark (w/v) significantly controlled astragal stem rot in the glasshouse experiments.

• Journal of Life Science
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• v.9 no.4
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• pp.368-374
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• 1999

Three soybean cultivars, Hwangkeum, Tanyeob and Enrei were planted in the same pot under glasshouse conditions to investigate the influence of the different soil water content such as pF 1.4(wet), 2.1(control) and 3.6(dry) on the transpiration rate, dry matter production and water requirement. The transpiration rate remained the high constant rates under the wet soil condition and the control than the dry condition, and showed a linear correlation between transpiration rate and solar radiation under the all condition of soil water. The transpiration rate highly increased in the morning, but dramatically decreased in the other time in a day. The dry matter production was higher under the conditions of wet soil and the control than that under the dry condition. Also, the dry matter production Tanyeob was higher than other cultivars under all soil water content. The water requirement was higher for Enrei and lower Tanyeob than the control.

• The Korean Journal of Applied Statistics
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• v.17 no.2
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• pp.185-196
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• 2004

It is an important research area in Integrated Pest Management System to estimate the pest density within plants, because the artificial controls such as spraying pesticides or biological enemies depend on the information of pest density. This paper studies the population density distribution of two-spotted spider mite in glasshouse roses. As the data were collected repeatedly on the same subject, Subject-Specific and Population Averaged approaches are used and compared.

• Korean Journal Plant Pathology
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• v.10 no.1
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• pp.64-67
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• 1994

Crown rot was found find tomatoes growing on a rockwool culture system in a glasshouse at Dongkwangyang in 1992. The disease occurred on the stem of 'Trust' tomato plants with 3~4 cluster of flowers. Infected plants showed stem girdling and necrosis at or slightly above the rockwool line. Internal tissues of crown and stem including cortex, vascular bundle, and pith became decayed resulting in a chocolate-brown discoloration extending no more than 10~15 cm above the crown. Diseased tomato plants with the similar symptoms were found at Ansung and Taejon where tomatoes were grown on either rockwool or soil in plastic greenhouses. The size of macroconidia of Fusarium isolated from a diseased plant was 26.0~41.6$\times$2.9~4.7${\mu}{\textrm}{m}$, and microconidia were formed on short monophialide and the size was 3.6~12.5$\times$2.9~3.6 ${\mu}{\textrm}{m}$. Morphological characteristics and inoculation tests indicated that the causal organism of the disease was Fusarium oxysporum.

• Journal of Bio-Environment Control
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• v.15 no.2
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• pp.167-172
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• 2006

The objective of this study was to determine the effects of substrate water content and electrical conductivity (EC) on the incidence of brown fruit stem and blossom end rot in glasshouse sweet pepper (Capsicum annuum cv. Special). Three levels of water content and EC had been treated since the first fruit reached 3cm in diameter: that is, 49 (low), 65 (medium), and 86% (high) for water content, and 2.4 (low), 4.2 (medium) and $6.3dS{\cdot}m^{-1}$(high) for EC. Shoot growth was reduced with decreasing water content, and it was lower in both high and low EC treatments than medium EC treatment. Fruit weight at harvest was greater in both medium and hish water content treatments than low water content treatment (158g vs 146g). High EC reduced fruit weight compared to or low EC treatments. The incidence of brown fruit stem increased with increasing water content and with decreasing EC. The highest incidence was shown in the high water content/low EC treatment (38%), which was considerably higher than 2.4% of the low water content/high EC treatment. Blossom end rot occurred in general in the low water content and/or high EC conditions. These results indicated that substrate water content and EC should be controlled differently according to the growth stage, to reduce the incidence of blossom end rot and brown fruit stem in glasshouse sweet pepper. First, to reduce blossom end rot incidence, water content should be maintained high (86%) and EC low ($2.4dS{\cdot}m^{-1}$) until Sweets after fruit set. Secondly, to reduce brown fruit stem incidence, water content should be maintained low (49%) and EC high ($6.3dS{\cdot}m^{-1}$), especially after completion of fruit growth.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.419-427
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• 2012

This study was carried out to investigate the effect of two shading methods, shading agent spray on the glasshouse and internal shading screen treatment, on the growth and fruit quality of paprika (Capsicum annuum L. 'Cupra' and 'Coletti') in summer season cultivation. In the shading agent treatment, a commercial shading agent diluted with water at a ratio of 1 : 4 was sprayed on the roof of a glasshouse. In the internal shading screen treatment, a 10~20% shaded screen was used during the day time when the sun radiation was greater than $700W{\cdot}m^{-2}$. Compared to the unshaded control, photosynthetic photon flux density (PPFD) decreased in the greenhouse in the shading agent (SA) and shading screen (SS) treatments by 20% and 30%, respectively. Lower air temperatures and higher relative humidities were observed in the SA than in both the control and the SS treatment. Time to reach the break point of humidity deficit $8g{\cdot}m^{-3}$ was 2 hours late in the SA than in both the control and the SS treatment. Compared to control, both the SA and the SS treatments showed lower instantaneous temperatures of leaf, fruit, and flower by $2^{\circ}C$, $5^{\circ}C$ and $3^{\circ}C$, respectively. There were no differences in number of branches, stem diameter, and leaf size among treatments although both shading treatments promoted plant height in both cultivars. Botrytis infection ratio declined with the SA treatment by 14.7% in 'Cupra' and 22.1% in 'Coletti' as compared to that in the control. Shading increased fruit size in both cultivars, whereas no differences were observed in the number of locules and thickness of fruit tissue among treatments. Shading treatment increased mean fruit weight by a range of 10 to 15 g per fruit, while it decreased soluble solids contents as compared to that in the control. Similar Hunter values were observed among treatments, while fruit firmness increased slightly in shading treatments. Compared to the control, shading treatments improved marketable fruits by 11.7~22.6% and increased the number of fruits per plant by 4~9.2 in both 'Cupra' and 'Coletti'. The results of this study indicate that shading agent application on the roof of glasshouse would be one of the most effective options to reduce heat stress imposed on the paprika crop in summer cultivation, resulting in improved crop growth and fruit yield.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.2
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• pp.154-159
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• 1995

In order to find out the effects of shading and nitrogen fertilizer on $NO_3^-$ accumulation in the edible parts of chinese cabbage, Cutivar, "Seoul", was cultivated in the pots under glasshouse condition with different rates of shading(0, 15, 30, 50, 75%) and nitrogen fertilization(recommended level, and double rate of recommended level). Leaf length, leaf width, yield (leaf weight), root width and root weight in the 15% shading rate showed the highest value, but decreased in the over 30% shading rates. The highest yield showed in the plot of the 15% shading rate with double rate application of recommended N level. High rate of shading increased the $NO_3^-$ accumulation, especially in midrib and outer leaf compared to leaf blade and inner leaf, respectively. The average $NO_3^-$ accumulation of edible parts of chinese cabbage are $4,872mg\;kg^{-1}$(outer midrib), $2,363mg\;kg^{-1}$(inner midrib), $1,405mg\;kg^{-1}$(outer leaf blade) and $727mg\;kg^{-1}$(inner leaf blade). $NO_3^-$ accumulation of outer midrib in the plots of double application of recommended N level were no difference between shading rate containing $5,000{\sim}6,000mg\;kg^{-1}$ $NO_3^-$, while in the plots of recommended N level it was increased by elevating shading rate. It was concluded that overuse of nitrogen fertiliration for chinese cabbage in glasshouse condition might lead to increase $NO_3^-$ accumulation. It could be advisable to cut out both the out leaf blade and outer midrib which might accumulate the high concentration of $NO_3^-$ before consumption.