• Journal of Plant Biotechnology
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• v.40 no.3
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• pp.156-162
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• 2013

Plant tolerance to drought is a beneficial trait for stabilizing crop productivity under water deficits. Here we report that genetically engineered Chinese cabbage expressing Arabidopsis $H^+$-pyrophosphatase (AVP1) shows enhanced physiological parameters related to drought tolerance. In comparison with wild type plants under soil water deficit stress created by cessation of irrigation, soil water potential in pot with AVP1-expressing plants was more rapidly decreased that might lead to increased relative water content in leaves, while both genotypes had indistinguishable wilting phenotypes. Transgenic plants subjected to drought treatment also exhibited higher photosystem II quantum yield in addition to lower electrolyte leakage and $H_2O_2-3,3^{\prime}$-diaminobenzidine content when compared to wild type plants.

• Journal of Korea Water Resources Association
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• v.42 no.2
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• pp.149-160
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• 2009

The objective of this study is to suggest parameter regionalization scheme which is integrated two multivariate statistical methods: principal components analysis(PCA) and hierarchical cluster analysis(HCA). This technique is to apply semi-distributed rainfall-runoff model on ungauged catchments. 7 catchment characteristics (area, mean altitude, mean slope, ratio of forest, water content at saturation, field capacity and wilting point) are estimated for 109 mid-sized sub-basins. The first two components from PCA results account for 82.11% of the total variance in the dataset. Component 1 is related to the location of the catchments relevant to the altitude and Component 2 is connected with the area of these. 103 ungauged catchments are clustered using HCA as the following 6 groups: Goesan 23, Andong 6, Imha 5, Hapcheon 21, Yongdam 4, Seomjin 44. SWAT model is used to simulate runoff and the parameters of the model on the 6 gauged basins are estimated. The model parameters were regionalized for Soyang, Chungju and Daecheong dam basins which are assumed as ungauged ones. The model efficiency coefficients of the simulated inflows for these three dams were at least 0.8. These results also mean that goodness of fit is high to the observed inflows. This research will contribute to estimate and analyze hydrologic components on the ungauged catchments.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.4
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• pp.405-410
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• 2012

This study was carried out to investigate the effect of harvest stage of rape on nutritive values and quality of round baled rape silage in field of forage crops of Department of Animal Resources Development, National Institute of Animal Science, RDA. Rape was harvested at three different growth stages (flowering, milk and dough stage) and ensiled at each harvest stages. The content of moisture of rape increased with delayed harvest maturity. However, the content of moisture of rape was controlled by pre-wilting (24 hr. and 48 hr). The content of moisture in dough stage was similar to that of haylage. The content of crude protein in round baled rape silage increased with delayed harvest maturity, but the contents of acid detergent fiber, neutral detergent fiber and total digestible nutrient decreased. The pH in all rape silage ranged from 3.8 to 4.4 at three different harvest stages, and pH in dough stage was higher than that of flowering and milk stages (p<0.05). The content of lactic acid of all rape silage increased with delayed harvest maturity (p<0.05), but the content of acetic acid decreased (p<0.05). And then, flieg's score revealed that there was an increase in order; flowering stage (100) = milk stage (100) > ripen stage (88).

• Weed & Turfgrass Science
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• v.4 no.4
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• pp.405-412
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• 2015

Forty schools having natural turf playgrounds were investigated by on-spot investigation and oral interviews with relevant school officials to find out basic information on turfgrass management practices of school playgrounds in Gyeonggi province. Average area of playground was $3,890m^2$ per school and $12m^2$ per student. Ninety five percent of turf playgrounds were managed by school staff and ninety percent of schools spent less than 5 million won per year for turf management. The difficulties in turfgrass management were considered as a major challenge for the schools, followed by turfgrass management cost. Among the management practices, school officials pointed out weed management as the most difficult work, followed by irrigation. The average number of fertilization and mowing was 2 and 6 times per year, respectively. About the half of playgrounds were irrigated only when there was wilting symptom. Zoysiagrass was the most popular choice for the school playgrounds and only three school playgrounds were established with pop-up irrigation system. Fourteen school playgrounds had good turf quality but the rest of school playgrounds had inadequate turf quality requiring minor or full renovation.

• Korean Journal of Medicinal Crop Science
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• v.28 no.2
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• pp.152-166
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• 2020

Background: Ginsenosides, which have various physiological activities, are known to be abundant in the leaves and roots of ginseng. Ginseng sprouts can be used as a fresh vegetable and roots, stems, and leaves of ginseng can be consumed. This study aimed to investigate the effect of carbon dioxide treatment and the modified atmosphere (MA) packaging method in suppressing quality deterioration during the distribution of ginseng sprouts. Methods and Results: Ginseng sprouts were packed using Styrofoam, barrier film + non gas treatment, barrier film + gas treatment, 15 ㎛ polyamide (PA) double film + non gas treatment, 15 ㎛ PA double film + gas treatment, 25 ㎛ PA film + non gas treatment, or 25 ㎛ PA film + gas treatment. Quality parameters including gas composition, relative humidity, chlorophyll SPAD (Soil Plant Analysis Development) value, firmness, and rate of quality loss in ginseng sprouts were monitored at the following temperatures: 20℃, and 10℃. Ginseng sprouts packaged with 25 ㎛ PA film showed loss in quality because of wilting owing to low relative humidity within the film. Chlorophyll and firmness did not differ between film and gas treatments. The time point at which the combined loss from softening and decay owing to fungal, and bacterial infection and wilt reached 20% was considered the limit of distribution. At 20℃, the packaging not included in the 20% distribution loss rate limit or up to 7 days was 15 ㎛ PA double film + gas treatment. At 10℃, the packaging not included in the 20% distribution loss rate limit for up to 18 days were barrier film + gas treatment and 15 ㎛ PA double film + gas treatment. Conclusions: The film packaging suitable for the distribution of ginseng sprouts was found to be the barrier film and PA film with low gas permeability and maintaining hygroscopicity at 95% relative humidity. To prevent the loss in quality of ginseng sprouts, gas treatment (8% of O₂ and 18% of CO₂) in the film was found to be more suitable than no gas treatment for inhibition of decay.

• Korean journal of applied entomology
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• v.21 no.2 s.51
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• pp.61-67
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• 1982

The strawberry cultivar Hokowase showing rapid wilting and death around harvest time was first found in the fold at Woongcheon, Chungnam province in 1974. The fungus, Fusarium oxysporum was isolated frequently from the crown, petiole and root of strawberry plants collected from Woongcheon and was pathogenic to Hokowase. The fungus abundantly produced micro-and macro-conidia and chiamydospore on PSA. The size of micro conidia, macro conidia and Chlamydospores was $5.0\~13.0\times2.5\~3.0,\;12.8\~62.5\times2.5\times50\mu\;and\;7.5\~13.8\times5.5\~12.5\mu$, respectively. Mycelial growth of the fungus was best between $25\~30^{\circ}C$ on PSA. The disease at Woongcheon occurred from the end of March and incidence of the disease increased from the beginning of May reaching $40.2\%$ of diseased Plants at the 1st part of June. In laboratory and field evaluation tests with twelve fungicides, Difolatan, Benlate T and Tospin M showed some control effects against the disease although they did not show ignificant differences in effects compared with that of the non-treatment. The cultivar Yachiyo, Daehak 1, Line 10-2, and Senga Sengana were highly resistant, and Harunoka and Empire were moderate resistant whereas Northwest and Hokowase were highly susceptible to the fungus under field condition.

• Korean journal of applied entomology
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• v.21 no.3 s.52
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• pp.153-158
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• 1982

The study was conducted to obtain the basic information on the diseases epidemics of vegetable crops grown in Namji, Jinju, Gimhae and Suncheon under the extremely varied and specified conditions, plastic film house. The disease survey was conducted from the end of April, 1951 to April 1982. Leaf mold and late blight were serious foliar disease in tomato during the seedling stage, especially when the infected seeds were sown. The diseases increased rapidly 35 days after seeding. In both continuous cultivation of cucumber and rotation with upland crops, incidence of Fusarium wilt was severe while incidence of the disease was negligible in cultivations after paddy rice or grafting on pumpkin. Downy mildew of cucumber was severe in Jinju and Suncheon area, however, it was not so serious in Namji area where the growing season of cucumber was unfavorable for the maximum disease incidence. Cucumber mosaic virus disease was prevalent in the areas surveyed and the disease incidence was increased rapidly after June. Powdery mildew prevailed at the early stage of cucumber growth after transplanting in Namji area. Root rot and wilting caused by Phytophthora capsici was as the most destructive disease in pepper grown under the vinyl house, especially in Namji and Jinju area where the pepper has been cultivated intensively. The Phytophthora attacked most parts of young plants during the winter time and then induced crown rot on the adults plants. Cultivation of pepper in vinyl house was almost impossible because of the Phytophora disease by the end of June. Virus diseases to tomato plants were prevalent throughout the surveyed area and the damage was also severe. In Jinju and Gimhae area leaf mold and late blight showed high infection rate in tomato during the harvest time.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.717-724
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• 2011

The objectives of this study were to analyze environment in the forest and growth characteristics for investigating the characteristics of Robinia pseudoacacia distribution in a Pinus thunbergii forest at the coast. As a result of analyzing inhibitory factors of Robinia pseudoacacia distribution in a Pinus thunbergii forest at the coast, it is considered that the salt level included in a sea wind is supposed to be the primary factor of the slow growth for Robinia pseudoacacia since brown leaves, wilting and early leaf fall have appeared in the 0m spot from the artificial dune which has the high salt level. However, the soil properties and light environment hardly have a effect on the growth of Robinia pseudoacacia because there is no difference among planting places. Also, the growth ring of the horizontal root in 2year individuals 0.1~0.2m away from the dune have been formed for 1 year only as a consequence of analyzing growth rings of Robinia pseudoacacia growing on the coast. It can be infered that the nourishment of the horizontal root from individuals growing on the coast have been provided for the first 1 year only. It is estimated that, in case of the nearby areas on the coast, it is not enough to provided nourishment to the horizontal root due to obstructing the growth of new individuals by a sea wind, so the growth of the horizontal root would be hampered. Therefore, it is considered that impedient Robinia pseudoacacia distribution in a Pinus thunbergii forest at the coast is caused by making no growth of new horizontal roots and newborn individuals.

• Korean Journal of Plant Resources
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• v.24 no.4
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• pp.445-455
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• 2011

This study was performed to develop a natural preservative which had the most successful effect on prolonging the vase life of cut flowers Rosa hybrida 'Enjoy'. To determine the effect of sucrose on vase life of cut roses, R. hybrida 'Enjoy', 0, 1, 3 or 5% of sucrose was mixed with Hypnum jutlandicum extract. The result showed that in the case of adding sucrose to extracts from H. jutlandicum, vase life of cut flowers was shortened, along with the cut flowers losing chlorophyll, becoming decolorized and finally showing wilting phenomenon. However, using hydroxy quinoline sulfate (HQS) and extracts from H. jutlandicum together exhibited an improved effect of prolonging vase life, especially when adding 100 $mg{\cdot}L^{-1}$ HQS, which had the effect of prolonging the vase life of R. hybrida 'Enjoy' the most. Regarding pH of extracts, 2 $mg{\cdot}L^{-1}$ of extracts from H. jutlandicum show originally pH 3.8. This was compared with adjusted extract solutions as pH 3.0, 4.0 or 5.0. The results showed that the solution of pH 3.8 had the most successful effect on prolonging the vase life of R. hybrida 'Enjoy'. Given all the results, H. jutlandicum extract (2 $mg{\cdot}L^{-1}$) and HQS (100 $mg{\cdot}L^{-1}$) was the most effective in prolonging the vase life of cut R. hybrida 'Enjoy'. Moss is expected to be worth developing as a natural preservative since it is easy to get and causes no damage to the environment.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.239-245
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• 2004

Storage quality of minimally processed onion as influenced by hot-water dipping was investigated to examine feasibility of mild heat treatment as efficient post-processing method. fresh onions were peeled, trimmed, and dipped in hot water at various temperatures ($50-80^{\circ}C$) for 1 min. Heat-treated onions were cooled, de-watered, packaged in low density polyethylene (LDPE) film pouches ($63\;{\mu}m\;thickness$), and stored at $10^{\circ}C$. Samples treated at higher temperatures ($70-80^{\circ}C$) showed significant increases in flesh weight loss and discoloration during storage as compared to others. Hot-water dipping remarkably reduced initial microbial load of prepeeled onions, with over 1 log cycle decrease in aerobic bacterial count. After 7 days storage, no significant differences in viable aerobe count were observed among treated and untreated samples, with both showing $10^{6}-10^{7}\;CFU/g$. For sensory attributes including discoloration, wilting, decay, and visual quality, onions treated with hot-water dipping at $60^{\circ}C$ scored highest. Results suggested hot-water dipping at specific condition as practical post-processing treatment could effectively prolong shelf life of minimally processed onion.