• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.107-113
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• 2013

The black soldier fly larvae are able to decompose various organic wastes such as livestock manures and food wastes. We tested whether the quality of the insect derived compost, i.e. larval feces, was comparable to that of a commercial fertilizer. Chemical analysis of Hermetia. illucens compost was suitable as a fertilizer. When the kidney bean (Phaseolus vulgaris L.) was raised on the culture soil treated with the H. illucens compost, the growth of leaf area, total dry weight and leaf dry weight increased significantly. The H. illucens compost is thought to act as an increasing factor of RGR (relative growth rate) from the beginning of growth and also had a great effect on the relative growth rate throughout the late stage of growth. There is high statistical significance between NAR (net assimilation rate) and RGR (relative growth rate), but no significance between RGR and LAR (leaf assimilation rate) of the treatments. In addition, the treatment of H. illucens compost promoted the thickness of leaves from the beginning of growth and the tendency of thickening leaves from the beginning of growth and the effect continued throughout the late period of growth. When mixed with 50% of H. illucens compost rather than 25%, it showed the greater effect on the plant growth.

• Korean Journal of Medicinal Crop Science
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• v.11 no.5
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• pp.364-370
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• 2003

Essential oil of Thuja occidental leaves was extracted by steam distillation method, and chemical composition of essential oil was analyzed by GC-MS. The essential oil was tested to antimicrorbiaI activity against 28 test microorganisms and antioxident assay through DPPH free radical scaveging test and insecticidal activity by mosquito insecticide assay. The major constituents in the essential oil of T. occidental were monoterpene as d-isothujone, ${\alpha}-thujone$, camphor, L-fenchone, and hornyl acetate. The essential oil have broad antimicrobiaI activity, which showed strong antimicrobiaI activity for Streptococcus pyogenes as bacteria, Alternaria alternata, Aspergillus niger, Aspergillus oryzae, Saccharomyces cerevisiae, and Streptococcus mutans as fungi. The essential oil also showed DPPH free radical scavenging ability at concentration of $36\;{\mu}{\ell}/m{\ell}$. In spraying and fumigation tests, the essential oil had strong insecticidal activity against mosquito.

• Journal of Bio-Environment Control
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• v.17 no.2
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• pp.170-175
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• 2008

To verify suitability of the developed nutrient solution for fertigation culture of cucumber, chemical changes of soil, growth characteristics and yield of cucumber as affected by conventional fertigation method (Control), the developed nutrient solution for fertigation culture (DNF) and Yamasaki cucumber recipe (YCR) were investigated. At 48 days after transplant, photosynthetic and transpiration rate of cucumber leaves were the highest in 3/2 strength of DNF and 1/2 strength of YCR, but not different with the Control, in the later growing period photosynthetic rate was the highest in 3/2 strength of DNF and YCR and was clearly different with the Control, transpiration rate was the highest in 3/2 strength of DNF and 1/2, 1 strengths of YCR. The growth and yield of cucumber, nutrient elements of cucumber leaves except for calcium were more in DNF and YCR than in the Control. Compared with pre-treated loam soil, pH of the soil was low and electric conductivity was high in all treatments, amounts of accumulated phosphorus, potassium, calcium, and magnesium were much in the higher concentrations per the kinds of nutrient solutions. From the above results, it was considered that the developed nutrient solution has suitability as nutrient solution for fertigation culture of cucumber.

• Journal of Life Science
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• v.14 no.5
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• pp.761-769
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• 2004

This study was investigated the occurrence of sclerotinia rot caused by Sclerotinia sclerotiorum at the major perilla cultivating area, Gangdong-dong, Gangseo-gu, Busan in 1998. The incidence of this disease ranged from 8.1 to 28.3% at Gangdong-dong area during the growing seasons. Symptoms of the disease initially appeared damping-off of infected stems and soft-rot on the leaves of perilla. Under the relatively high humidity, abundant white mycelia of the pathogen formed on the lesion developed into black sclerotia later and the infected leaves were finally fell down. Sixteen isolates, Sl-S16, isolated from diseased lesions showing typical symptoms, and pathogenicity was tested using mycerlial disks. Among them, S2 isolate showing the most strong pathogenicity was selected and identified as Sclerotinia sclerotiorum on the basis of morphological and cultural characteristics. For biological control, an antagonistic bacteria, N4 isolate which effectively inhibited not only mycelial growth of S2 isolate but also suppress sclerotinia rot on the pot assay, was selected and identified as Bacillus megaterium according to Bergey's manual and API system., Wettable powder type, N4 formulation using B. megaterium N4 isolate was developed and estimated its control effect on perilla crops in a plastic house. As a results, N4 formulation which applied before 3 days inoculation of pathogen was effectually controlled Sclerotinia rot as the control value of 98.0%, was more effective than chemical fungicide, benomyl showing the control value of 78.0%. This is the first report of wettable powder formulation as a biocontrol agent using B. megaterium N4 against Sclerotinia rot caused by S. sclerotiorum on perilla.

• Journal of Ginseng Research
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• v.33 no.3
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• pp.234-239
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• 2009

This study aims to establish the directions for the optimal nutrient contents determined by soil and leaf analyses. The study is to be used as a source for basic information in investigating the effects of nutritional environment on ginseng growth at the fields of Ansung region in Gyeonggi province. The physical property of soil porosity is closely related to ginseng growth, with more than 50% of good growth in the field. The optimal range of chemical properties in soil was analyzed as 0.20-0.28% T-N, 500-900 mg/kg Av.P$_2$O$_5$, and 2.3-3.5 cmol$^+$/kg Exch.Ca. The optimal range of inorganic nutrient contents in leaves was also analyzed. P value was less than 0.25%, and Mg was more than 0.22%. Other elements were not found clearly. The ratios of N/P, N/Mg, K/Mg, and Ca/P of leaves with good growth in the field showed 10<, 10-13, <14, 1<, respectively. In addition, the Ca:Mg:K ratio of the Exch.cation (cmol$^+$/kg) may be useful as an indicator in the assessment of plant growth in ginseng.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1515-1522
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• 2008

Monitoring the pesticide residues in agricultural products is essential to protect consumers, obtain data for risk assessment, and ensure fair trade practices. We developed a multi-residue method for the analysis of 37 pesticides with different physico-chemical properties in agricultural products and analyzed the amount of pesticide residues on about 1,000 samples circulated in South Korea. The samples consisted of 26 different types of agricultural products selected at markets in 14 major cities; cereals (2 species), nuts (1 species) potatoes (1 species), beans (2 species), fruits (3 species), vegetables (16 species), and mushrooms (1 species). In this study, residual pesticides were detected in 23 samples (2.2%) and one sample was detected to be over maximum residue limits (MRLs, 0.1%) for pesticides in foods by the Korea food code. In leafy vegetables such as pepper leaves, radish leaves, cham-na-mul, shin-sun-cho, crown daisy, chwi-na-mul and citrus fruits such as kumquat, 8 kinds of pesticides were detected. Specially, diazinon were detected over MRLs and also, endosulfan, ethoprophos and phenthoate were detected frequently. Based on these results, we investigated the risk assesment from amount of residual pesticide, total %ADI was 1.262%, but the value has not effected on human health.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.6
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• pp.844-850
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• 2002

The potential nutritive value was studied on leaves of seven fodder trees in Central Sudan during dry season at two distinct periods, the early dry and the late. The chemical composition, mineral concentration, in vitro organic matter digestibility (IVOMD), in situ OM or nitrogen degradability and estimated metabolizable energy showed a wide variation among fodder tree species and between different periods of the dry season. Crude protein (CP) ranged from 285 to 197 g/kg DM at early dry season, with a significant reduction in late dry season. Ziziphus spina-christi and Balanites aegyptiaca showed the least reduction in CP content. The NDF, ADF and lignin were about 200, 160 and 19 g/kg DM, respectively at the early period, and significantly increased at the late period of the dry season, except for lignin of Z. spina-christi. For mineral concentration, all fodder tree leaves were rich in calcium but poor in phosphorus. In situ OM degradability significantly decreased at the late period of dry season, but values remained as high as over 600 g/kg OM. At both periods, Z. spina-christi showed the highest value, while the lowest was recorded in Acacia seyal. The IVOMD showed a similar trend to those of in situ OM degradability, except for A. seyal. The nitrogen degradability was highest in B. aegyptiaca and lowest in Z. spina-christi at both periods. A significant and positive correlation had existed between CP and IVOMD or in situ OM degradability (r=0.68, p<0.05; r=0.77, p<0.05, respectively). Also, a significant but negative correlation was found between condensed tannins and nitrogen degradability (r=-0.87, p<0.01). Results demonstrated that Z. spina-christi potentially has a good nutritive value as dry season feed or supplement, while A. seyal tends to be less promising. A. nubica and B. aegyptiaca may be a useful source for degradable protein, even though it may have a limited supply of energy to animals. A. tortilis, A. mellifera and A. ehrenbergiana may have potential value for a supplementation of energy or protein, if they were harvested in the early dry season or in wet season as preserved feed. It is highly recommended to supplement with an appropriate amount of phosphorus when these fodder trees were used.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1995.06b
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• pp.27-53
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• 1995

In plant pathology there is an increasing necessity for improved cytological techniques as basis for the localization of cellular substances within the dynamic fine structure of the host-(plant)-pathogen-interaction. Low temperature (LT) preparation techniques (shock freezing, freeze substitution, LT embedding) are now successfully applied in plant pathology. They are regarded as important tools to stabilize the dynamic plant-pathogen-interaction as it exists under physiological conditions. - The main advantage of LT techniques versus conventional chemical fixation is seen in the maintenance of the hydration shell of molecules and macromolecular structures. This results in an improved fine structural preservation and in a superior retention of the antigenicity of proteins. - A well defined ultrastructure of small, fungal organisms and large biological samples such as plant material and as well as the plant-pathogen (fungus) infection sites are presented. The mesophyll tissue of Arabidopsis thaliana is characterized by homogeneously structured cytoplasm closely attached to the cell wall. From analyses of the compatible interaction between Erysiphe graminis f. sp. hordei on barley (Hordeum vulgare), various steps in the infection sequence can be identified. Infection sites of powdery mildew on primary leaves of barley are analysed with regard to the fine structural preservation of the haustoria. The presentation s focussed on the ultrastructure of the extrahaustorial matrix and the extrahaustorial membrane. - The integration of improved cellular preservation with a molecular analysis of the infected host cell is achieved by the application of secondary probing techniques, i.e. immunocytochemistry. Recent data on the characterization of freeze substituted powdery mildew and urst infected plant tissue by immunogold methodology are described with special emphasis on the localization of THRGP-like (threonine-hydrxyproline-rich glycoprotein) epitopes. Infection sites of powdery mildew on barley, stem rust as well as leaf rust (Puccinia recondita) on primary leaves of wheat were probed with a polyclonal antiserum to maize THRGP. Cross-reactivity with the anti-THRGP antiserum was observed over the extrahaustorial matrix of the both compatible and incompatible plant-pathogen interactions. The highly localized accumulation of THRGP-like epitopes at the extrahaustorial host-pathogen interface suggests the involvement of structural, interfacial proteins during the infection of monocotyledonous plants by obligate, biotrophic fungi.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.15
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• pp.145-153
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• 1974

Five different levels of Ethephon were treated on tobacco cultivar yellow Special A and Coker and harvested for curing. Changes in dehydration properties, yellowing, chlorophyll, nicotine, sugar and starch contents during the processes of curing were studied in order to justify feasibility of adoption an idea of 3-stage-curing method instead of the 5-stage. Ethephon-treated-tobacco leaves showed marked degradation of chlorophyll, greater dehydration and greater reduction in nicotine contents while little change in either sugar, starch and other chemical components. They showed also shorter hours of curing period allowing possible curing response at a relatively low temperature than those without treatment. Thus they undergo only 3 stages of flue-curing processes, yellowing, calor-fixing and vein-drying, and need 72 hours to finish curing, but the ordinary leaves need 100 hours for it.

• Applied Microscopy
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• v.35 no.2
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• pp.97-104
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• 2005

Plant epidermis consists of relatively unspecialized cells and more specialized cells of various structure and function. Trichomes are specialized cells originated from the epidermis and much attention has been paid to the plants developing trichomes with peculiar structure and function. The present study has been undertaken to examine the trichome type noticed in the leaf epidermis of Althaea rosea using scanning electron microscopy. Four types, namely simple, short-and long-tufted, and glandular hairs, were detected in their epidermis. Their Distribution, frequency and structure varied by the development and epidermal surface. The most frequently distinguished type was the tufted ones growing in young leaves of the abaxial epidermis, while the simple hairs were rare throught the examination. The short-tufted hairs branched up to seven times having each branchlet about $160{\sim}210{\mu}m$ in length at maturity. The long-tufted hairs exhibited up to ten branchlets, where branchlets could reach up to $900{\sim}1,000{\mu}m$ long when fully expanded. Glandular trichome was the peltate type comprising $1{\sim}2$ secretory head cells, 2 stalk cells and a basal cell. The short peltate glandular hairs, usually not exceeding $40{\mu}m$, differentiated more along the areoles in the adaxial epidermis. The function of these trichomes in A. rosea has been still obscure, but it has been speculated that they probably play a role in protection; non-glandular ones possibly providing a defense against insects and secretory glandular type participating in chemical defense. Structural features of these trichomes at cellular level will be discussed in the following study of transmission electron microscopy.