• Korean journal of applied entomology
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• v.28 no.1
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• pp.10-15
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• 1989

This studies were carried out to selected high pathogenic nuclear polyhedrosis viruses(NPVs) against Pseudaletia(=Leucania) separata for the introduction of microbiol control of the insect NPV in Korea. Among 21 NPVs, Sesamia inferens and 4 P. separata NPV strains were highly pathogenic against P. separata when fed orchard grass leaves smeared virus suspension on the 2nd instar larvae. Three NPV strains (LsNPV-F, LsNPV-G, LsNPV-Y) were more susceptible to the younger instar than the older instar P. separata larvae when fed artificial diet mixed with the virus to the insect.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1997.05a
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• pp.23-27
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• 1997

Bio-Green(B.G.) functional water was manufactured by Kyungwon Enterprise Co. through a series of processes ; water longrightarrow ultra-purification longrightarrow adding catalysts longrightarrow energy imprinting fermenting with energized water + zeolite and others + photosynthetic bacteria in fermenter longrightarrow filtering. Control(0), 5 or 10 liters of B.G. functional water were supplied to the orchard soil under canopy of 10 year old 'Tsugaru'/M26 apple trees on March 20, May 20 and June 20, 1995, respectively. Some orchard soil characteristics, not only pH, but also Ca and Mg of exchangeable cations were increased by supply with B.G. functional water. However, P$_2$O$_{5}$, K, and B contents were not influenced by the treatment. At harvest time soluble solid content of flesh and anthocyanin of fruit skin were increased by the treatment. B.G. functional water treatment showed higher root activities, and photosynthesis of leaves than that of control. Also B.G. functional water treatment showed higher Ca content in fruit skin and flesh tissues, whereas not affected N, K, and Mg contents. During storage at 4$^{\circ}C$ cold room, the more volume of B.G. functional water supply showed lower bitter pit symptom. Respiration and ethylene evolution in fruit were decreased, while fruit firmness increased by the treatment during storage.e.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.237-241
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• 2005

The physical and chemical characteristics of soils in a small watershed were investigated and the effect of geology and land use on soil quality were examined by using multivariate statistical methods, principal components analysis and discriminant analysis. It was considered that the accumulation of salts in the farmland soils indicated by electrical conductivity, contents of cations and anions and pH was caused by fertilizer input during cultivation. The contents of inorganic components are increased as following order: upland > orchard > paddy field > forest. The results of two discriminant analyses using water extractable inorganic components and their ratios by land use were also clearly classified by discriminant function 1 and 2. In discriminant analysis by components, discriminant function 1 indicated the effect of fertilizer application and increased as following order: upland > orchard > paddy field > forest soil.

• Journal of Korean Society on Water Environment
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• v.30 no.1
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• pp.8-15
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• 2014

In this study, regression equation was analyzed to estimate non-point source (NPS) pollutant loads in orchard area. Many factors affecting the runoff of NPS pollutant as precipitation, storm duration time, antecedent dry weather period, total runoff density, average storm intensity and average runoff intensity were used as independent variables, NPS pollutant was used as a dependent variable to estimate multiple regression equation. Based on the real measurement data from 2008 to 2012, we performed correlation analysis among the environmental variables related to the rainfall NPS pollutant runoff. Significance test was confirmed that T-P ($R^2=0.89$) and BOD ($R^2=0.79$) showed the highest similarity with the estimated regression equations according to the NPS pollutant followed by SS and T-N with good similarity ($R^2$ >0.5). In the case of regression equation to estimate the NPS pollutant loads, regression equations of multiplied independent variables by exponential function and the logarithmic function model represented optimum with the experimented value.

• Korean Journal of Environmental Agriculture
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• v.26 no.4
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• pp.279-285
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• 2007

Soil physical properties in organic farming apple orchard were evaluated in relation to conventional farming to better understand the effects of organic farming system on soil quality. Two adjacent apple orchards, matched by soil type, were chosen to ensure the same pedological conditions except management system. Soil samples were collected from middle of two adjacent trees along the tree line at two depths of 5-20 and 20-35 cm in September 2006. Contents of organic matter in organic farming soil were twice as much as those found in soil of conventional farming. The higher level of organic matter in organic farming soil was reflected through a consequent trend in improved soil physical properties. Organic farming produced greater aggregation in >2 mm size and increased aggregate stability. Bulk density was lower by 13% and hence porosity was higher in soils of organic farming as compared with conventional farming. Water holding capacity was significantly greater with organic farming by >17% over conventional farming. The capacity of organic farming to improve soil physical properties can be contributed to the regular application of relatively large amount of organic materials and the sustainable ground-cover managements, mulching with compost and cover crop cultivation.

• Journal of Biosystems Engineering
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• v.36 no.3
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• pp.171-179
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• 2011

Facing the current hikes of labor wage and high oil price, it is needed to have energy-saving machinery which also enables us precise farm operations. Thus, it was necessary to develop a safe machine which allows secure and pleasant works along orchard slopes. In this study, a lifting utility with balance-controlled platform was developed. The platform utility could maintain to level the workbench while driving along slopes. Even the machine body was driven at the tilt angle ranges of ${\pm}20^{\circ}$, the platform bench could be maintained within ${\pm}0.5^{\circ}$ of a gimbal angle. In addition, the machine lifted up to 2.0 m using an electric-hybrid driving mechanism with a low noise. A tandem hybrid power source was developed with a DC 72 V, 100 AH for the Deep-Cycle batteries, charged with 3.5 kW gasoline generator as an auxiliary power source. HST, which is one of the CVT's, was adopted as a transmission device, and a crawer track was used for the safety of the vehicle against tip-over. The maximum lifting height of platform was is 2,500 mm, and the maximum extendable width was 2,900 mm.

• The Korean Journal of Mycology
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• v.26 no.1 s.84
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• pp.97-102
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• 1998

VA-mycorrhizal spores were collected from the 14 citurs orchards of different soil textures and locations in Cheju island. Five species and two kinds of spores were identified as based on the morphological characteristics of the spores; Acaulospora bireticulata, Glomus deserticola, G. geosporum, G. vesiculiferum, and Sclerocystis pachycaulis. Additionally, two kind spores of Acaulospora were also observed but difficult to be identified in this moment. Glomus deserticola and unidentified spores of Acaulospora (brown spores sized 90 to $125\;{\mu}m$ in diameter) were most frequently observed in the all soil specimens in Cheju, while the other kinds of spores were rarely observed in the soil of Cheju.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.1
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• pp.15-21
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• 2015

The use of cover crops has a beneficial effect on sustainable soil management in pear orchards. We aimed to compare changes in soil chemical properties and biota with the use of different cover crops. We tested the effects of five cover plants, including hairy vetch, orchard grass, rattail fescue, rye, and perennial ryegrass. Use of different cover crops had a minimal impact on soil chemical properties through three year experiments. The aboveground biomass was greatest with the use of rye. The potential amounts of returnable N and P were highest when leguminous hairy vetch was used as a cover plant. Changes in the composition of the microbial community were investigated by phospholipid fatty acid (PLFA) analysis. Microbial PLFAs were highest with the use of rattail fescue and lowest with the use of hairy vetch. Minimal changes in the abundances of nematodes and microarthropods suggested that there was no bottom-up control in the soil ecosystem. The results also show that increases in aboveground biomass and nutrient content with the use of cover crops may not promote the abundance of soil organisms.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.3 no.1
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• pp.7-12
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• 2022

Farming practices that balance environmental friendliness with biodiversity are increasingly valuable. Wild plants on farmlands compete for nutrients with crops and create a crucial microhabitat and resources for animals such as natural enemies. Investigating farmlands and their surrounding plants with limited human and material resources has become an essential aspect of evaluating the agricultural ecosystem services. This study investigated plants in six agricultural long-term ecological research sites in Taiwan from 2017 to 2020 to determine the ideal season for investigation. Cluster analysis was performed to group habitats with similar plant composition, and the species-area curves of the clusters in each season were created. The results indicated that the agricultural ecosystem could be divided into farmlands, banks, orchards, and tea gardens. The habitats were divided into farmland, bank, Chia-Yi orchard, Gu-Keng orchard, and tea garden clusters. Ground plant cover can be investigated all year with at least 18 quadrats. However, if human and material resources are limited, 10 quadrats should be the minimum for farmlands in autumn and for the other microhabitats in spring. The minimum number of quadrats is 10 for banks, 17 for orchards, and 9 for tea gardens.

• The Korean Journal of Mycology
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• v.51 no.4
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• pp.491-504
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• 2023

To explore fungal diversity in orchard soil where fire-blighted apple trees are buried, we collected soil samples from apple orchards in Chungju, Korea. Fungal isolates were obtained from DG18 agar and identified at the species level based on morphological features and phylogenetic analyses. The colony characteristics and microstructures were examined using a light microscope and a scanning electron microscope after culturing on potato dextrose agar (PDA), malt extract agar (MEA), Czapek yeast agar (CYA), and oatmeal agar (OA) The PCR-amplified products of the ITS1-5.8S-ITS2 region and 28S large subunit of the nuclear ribosomal RNA gene, as well as partial sequences of the β-tubulin, calmodulin, and translation elongation factor 1-α genes were sequenced and analyzed phylogenetically. Seven previously unknown fungal species were explored in Korea. All samples, including Aspergillus aureolatus, Botryotrichum atrogriseum, Dactylonectria novozelandica, Fusarium denticulatum, Paecilomyces tabacinus, Sarcopodium tibetense and Talaromyces stollii, had ascomycetes. Herein, we report their descriptions and features.