• Journal of Korean Society of Forest Science
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• v.95 no.6
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• pp.743-750
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• 2006

Poplars and willow were planted to identify suitable species and varieties for landfill reclamation at the Sudokwon Landfill Site in 1997. Survival rate, growth performance, vitality, visible foliar injury by pollutants, fungi, and leaf insects, and stem borer damage have been investigated for 10 clones of 4 poplar species and 2 clones of one willow species from 1997 to 2005. The average survival rates of poplar and willow clones were drastically decreased from 90% in 1997 to 53% in 2005. Among poplar species, Populus alba ${\times}$ P. glandulosa showed the highest mean survival rate of 66%, while Populus koreana ${\times}$ P. nigra var. italica and Populus euramericana were the lowest of 41%, respectively in 2005. Clivus, which is one of the clones from Populus alba ${\times}$ P. glandulosa, showed the highest survival rate of 73%. For mean height, Ec028 clone(P. euramericana) showed the highest of $11.2m{\pm}2.1m$ and followed by Clivus of $11.0m{\pm}2.0m$. Clone 131-27(Salix alba) was the lowest of $7.8m{\pm}1.6m$. Vitality, defoliation, visible foliar damage, and stem borer damage were significantly different among clones. Most of Populus alba ${\times}$ P. glandulosa and Salix alba clones seemed to have strong vitality and to be tolerant to various stresses at the site. However, Populus nigra ${\times}$ P. maximowiczii was sensitive to the stress. We have selected 5 clones in total: Clivus as the best clone for waste landfill reclamation, and additionally two Salix clones 131-25, 131-27 and two clones of Populus alba ${\times}$ P. glandulosa (72-9, 72-16) have been selected. These five clones could be supplied for planting at sites having an environment similar to the Sudokwon Landfill Site.

• The Korean Journal of Ecology
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• v.26 no.3
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• pp.143-150
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• 2003

Korea has plentiful precipitation but rainfall events concentrate on several months of rainy season in her weather condition. Korea, therefore, experiences drought for a given period every year. Moreover the soil has usually low water holding capacity, as it is composed coarse particles originated from the granite. Response of several oaks and the Korean red pine (Pinus densiflora) on water stress showed that water budget was significant factor determining vegetation distribution. In addition, dehydration level due to cold resistance mechanism of several evergreen plants during the winter season was closely related to their distribution in natural condition. Experimental result under water stress showed that the Korean red pine was very tolerant to desiccation but the seedlings showed high mortality during the dry season. The mortality tended to proportionate to soil moisture content of each site. A comparison between soil moisture content during June when it is severe dry season and moisture content of the culture soil when the pine seedlings reached the permanent wilting point due to water withheld proved that high mortality during the dry season was due to water deficit. Water potential of sample plants measured during the exposure experiment to the air pollutant showed a probability that water related factors would dominate the occurrence of visible damage and the tolerance level of sample plants. In both field survey and laboratory experiment, plants exposed to air pollution showed more rapid transpiration than those grown in the unpolluted condition. The result would due to injury of leaf surface by air pollutants. Aluminum (Al/sup 3+/) increased in the acid soil not only inhibits root growth but also leads to abnormal distribution of root system and thereby caused water stress. The water stresses due to air pollution and soil acidification showed a possibility that they play dominating roles in inducing forest decline additionally to the existing water deficit due to weather and soil conditions in Korea. Sludge, which can contribute to improve field capacity, as it is almost composed of organic matter, showed an effect ameliorating the retarded growth of plant in the acidified soil. The effect was not less than that of dolomite known in widely as such a soil ameliorator. Litter extract contributed also to mitigate the water stress due to toxic Al/sup 3+/. We prepared a model showing the potential interaction of multiple stresses, which can cause forest decline in Korea by synthesizing those results. Furthermore, we suggested restoration plans, which can mitigate such forest decline in terms of soil amelioration and vegetation restoration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.697-704
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• 2013

The inhibitory effect of ethanol extracts from Curdrania tricuspidata leaves (CTL) on osteoarthritis was investigated in primary cultured rat cartilage cells and a monosodium-iodoacetate (MIA)-induced arthritis rat model. To identify the effects of CTL 80% ethanol extracts (CTL80) and CTL 10% ethanol extracts (CTL10) against $H_2O_2$ treatment in vitro, cell survival was measured by the MTT assay. Cell survival after $H_2O_2$ treatment increased with CTL80 and CTL10 close to normal up to $300{\mu}g/mL\;H_2O_2$. The mRNA expression of matrix metalloproteinases (MMPs) was determined MMP-7 and MMP-13 (known catabolic factors), were significantly inhibited by CTL 80 and CTL10; a $200{\mu}g/mL$ dose of CTL80 especially decreased MMP-13 expression. In vivo, osteoarthritis was induced by an intra-articular injection of MIA into the knee joints of rats, then CTL80 and CTL10 orally administered daily for 35 days. After the animals were sacrificed, histological evaluations of their knee joints revealed a reduction in polymorphonuclear cell infiltration and smooth synovial lining in the CTL80-500 group. Micro-CT analysis of hind paws from CTL80-500 and CTL10 showed a protection against osteophyte formation, soft tissue swelling, and bone resorption. In conclusion, CTL ethanol extracts are effective in ameliorating joint destruction and cartilage erosion in MIA-induced rats. CTL decreases and normalizes articular cartilage through preventing extracellular matrix degradation and chondrocyte injury, and could potentially serve as a therapeutic treatment for humans.

• Research in Plant Disease
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• v.21 no.2
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• pp.58-66
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• 2015

This study was conducted to evaluate control efficacy of a fermented food 'Cheonggukjang' against cucumber powdery mildew caused by Sphaerotheca fuliginea in greenhouse. Sterilized Daepung beans were inoculated with the rice straw as natural inoculum and then incubated for 72 hrs at $42^{\circ}C$ in the household cheonggkjang maker. After 72 hrs of cheonggukjang fermentation, white zymogens were grown on the surface of a sterile Daepung beans. The pH of the 72 hrs fermented soybean was not significantly changed and electrical conductivity was found to increase by about 2 times than before fermentation. The population density of soybean zymogen showed a peak of growth at 60 hrs after fermentation and the concentration of zymogen was $8.2{\times}10^7cfu/ml$. Soybean zymogen form of the colony was divided into three kinds of bacteria and a white and a large colony (WL) was predominant bacteria among those up to 60 hrs of fermentation. To control the cucumber powdery mildew, diluted solutions of cheonggukjang was applied from 6.0% to 30.0% on cucumber leaves and they showed injury symptoms on cucumber leaves in more than 15% of them. However, more than 6.0% diluted cheonggukjang solutions showed more than 77.8% control effect of cucumber powdery mildew at 15 days after treatment. The fermented bacteria of Chenggukjang were well established in the cucumber leaf area at 15 days after treatment. The antifungal activity of 10% diluted cheonggukjang solutions was excellent for four species of plant fungal pathogens, Colletotrichum gloeosporioides, Sclerotinia cepivorum, Rhizoctonia sloani and Phytophthora capsici in the dual culture test. Results indicated that foliar application of Cheonggukjang solution could be used for the control of powdery mildews occurring on organically cultivated cucumber.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.2
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• pp.142-149
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• 2016

'Shinseong', a winter forage triticale cultivar (X Triticosecale Wittmack), was developed at the Department of Rice and Winter Cereal Crop, NICS, RDA in 2015. The cultivar 'Shinseong' was selected from the cross RONDO/2$^*$ERIZO_11//KISSA_4/3/ASNO/ARDI_3//ERIZO_7 by CIMMYT (Mexico) in 1998. Subsequent generations were handled in pedigree selection programs at Mexico from 1999 to 2004, and a line 'CTSS98Y00019S-0MXI-B-3-3-5' was selected for earliness and good agronomic characteristics. After preliminary and advance yield testing in Korea for 3 years, the line was designated 'Iksan47'. The line was subsequently evaluated for earliness and forage yield in seven locations, Jeju, Iksan, Cheongwon, Yesan, Gangjin, Daegu, and Jinju from 2013 to 2015 and was finally named 'Shinseong'. Cultivar 'Shinseong' has the characteristics of light green leaves, yellow culm and spike, and a medium grain of brown color. The heading date of cultivar 'Shinseong' was April 24 which was 3 days earlier than that of check cultivar 'Shinyoung'. The tolerance or resistance to lodging, wet injury, powdery mildew, and leaf rust of 'Shinseong' were similar to those of the check cultivar. The average forage dry matter yield of cultivar 'Shinseong' at milk-ripe stages was $15MT\;ha^{-1}$, which was 3% lower than that ($15.5MT\;ha^{-1}$) of the check cultivar 'Shinyoung'. The silage quality of 'Shinseong' (6.7%) was higher than that of the check cultivar 'Shinyoung' (5.9%) in crude protein content, while was similar to the check cultivar 'Shinyoung' in acid detergent fiber (34.6%), neutral detergent fiber (58.6%), and total digestible nutrients (61.6%). It showed grain yield of $7.2MT\;ha^{-1}$ which was 25% higher than that of the check cultivar 'Shinyoung' ($5.8MT\;ha^{-1}$). This cultivar is recommended for fall sowing forage crops in areas in which average daily minimum mean temperatures in January are higher than $-10^{\circ}C$.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.376-387
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• 2019

Melons are mostly grown in soil, but it is susceptible to damage due to injury by continuous cropping such as Fusarium wilt and root rot. Hydroponic cultivation system can overcome the disadvantages of soil cultivation with precise nutrition management and a clean environment. When using the coir substrate, the most environmentally friendly organic substrate used for hydroponics, it is analyzed how the growth and fruit quality of the melon depends on the ratio of chips and dust and the amount of irrigation. The purpose of this study was to provide the basic data of melon hydroponics when cultivated in spring. The two types of the coir substrates used in the experiments were chip and dust ratios of 3 :7 and 5 : 5 respectively. The substrate with high dust ratios had excellent physical characteristics, such as container capacity and total porosity, and the drainage EC level showed a high value of $3.0-6.8dS{\cdot}m^{-1}$. When the amount of irrigation is provided based on the drainage rate, the group provided the nutrient solution on the basis of 10% drainage supplied 91 L per plant, which was reduced by about 30% compared to the group with the highest water supply. In addition, the total drainage showed less than 10 L per plant with a minimum water supply and was reduced by 30 - 70% in substrate with a high dust rates. In substrate with high water supply and high dust ratio, leaf growth and fruit enlargement were good, and the soluble solids content varies greatly from cultivar to cultivar. If you provided the amount of irrigation based on 10% drainage rate, the fruit weight will be decreased, but the amount of irrigation can be reduced. Therefore, it is considered that managing the water & nutrient properly taking into account the characteristics of coir substrate and cultivar can produce melon of uniform quality using hydroponics.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.385-392
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• 2012

This study was conducted to find out the optimum cropping system for the stable production of forage crops in the newly reclaimed land located at Gwanghwal and Gyehwa region of Saemangum reclaimed tide land from October, 2009 to October, 2011. Whole crop barley (WCB), Rye, Italyan-ryegrass (IRG) as winter crops and Corn, Sorghum${\times}$sudangrass hybrid (SSH) as summer crops were cultivated. Soil chemical properties, nutrient uptake, feed value, growth and yield were examinated. The testing soil was showed saline alkali soil where the contents of organic matter, available phosphate and exchangeable calcium were very low, while exchangeable sodium and magnesium were higher. Changes of soil salinity during the growing season of forage crops were less than 0.2%, and the growth of forage crops was not affected by salt injury. Standing rates of winter crops were higher in the order of Rye, WCB, and IRG, while the dry matter yield of winter crops was higher in the order of IRG, Rye and WCB. The highest crude protein (CP) content was recorded in IRG, and total digestive nutrients (TDN) contents were increased in the order of WCB, IRG, and Rye. The TDN content was higher in corn, whereas other feed value was higher in SSH. The content of mineral nutrients on stem, leaf and grain in IRG, Corn were high. After experiment pH was lowed, contents of exchangeable magnesium, sodium and organic matter were decreased while contents of total nitrogen, available phosphate and exchangeable potassium, calcium were increased. Winer crops and summer crops after continually cultivating in cropping system, fresh matter yield increased, compared to WCB-Corn (74,740 kg $ha^{-1}$), IRG-SSH 10%, IRG-Corn 7%, Rye-SSH 6%, Rye-Corn and WCB-SSH 3%. Dry matter yield increased, compared to WCB-Corn (20,280 kg $ha^{-1}$), IRG-SSH 7%, Rye-SSH 6%, IRG-Corn/Rye-Corn/WCB-SSH 3%. The TDN yield increased, compared to WCB-Corn (13,830 kg $ha^{-1}$), IRG-SSH 2%, WCB-SSH and IRG-Corn 1%. Therefore, we suggest that the crop combination of IRG-SSH and WCB-SSH would be preferred for silage stable production.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.202-210
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• 1985

Requirements in weed control in a mulberry field are much similar to those in orchards, but also feature a longer period of weed control of various kinds of persistent weeds, i.e., spring, summer, and winter annuals as well as perennials. In addition the mulberry tree is relatively more sensitive to herbicide injury. Hence, very few herbicides have been used in mulberry field. The present study was conducted to evaluate the usefulness of oxyfluorfen in comparison with alachlor and simazine, which are registered for ordinary mulberry field in Korea, for weed control efficacy in the new, rapidly increasing practice of transparent polyethylene-film mulched and densely planted younger mulberry culture. Dominant spring weeds were Galium spp., Erigeron spp., Polygonum senticosum, and Chenopodium spp. in the non-mulched interbed area in contrast to the Digitaria spp. and Potulaca spp, under mulch. Dominant summer weeds were Digitaria spp., Portulaca spp., Erigeron spp., Artemisia spp. and Calystegia japonica in the non-mulched interbed area while weeds did not occur significantly during summer under mulch which were shaded by vigorously growing mulberry trees. The weeds occurred under mulch in spring reduced shoot growth of young mulberry tree resulting in the reduced yield of mulberry leaves for silkworms. The weeds occurred in the interbed area did not affect until May, but interfered later summer- and fall-growth of mulberry tree. Early single spring application of alachlor(EC), simazine(WP) or oxyfluorfen(EC) at a rate of 650 g, 750 g or 350 g ai per ha, respectively, controlled most annuals satisfactorily to fall in the mulched bed area. In the nonmulched interbed area, however, thrice does of alchlor or simazine was necessary for satisfactory control of spring weeds, followed by summer application of alachlor or simazine at twice dose level as tank mixture with paraquat at 490 g ai per ha for satisfactory control of summer to fall weeds. Single spring application of oxyfluorfen at a rate of 1400 g ai per ha was persistently effective to control satisfactorily even summer and fall weeds. However, heavy rainfall splashed soil borne oxyfluorfen to the lower branch leaves causing some leaf burns. Spring application of oxyfluorfen at a rate of 350 g ai per ha followed by summer application of oxyfluorfen and paraquat tank mixture (350 g ai + 490 g ai) was the best choice for the non-mulched interbed area weed control among the treatments.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.15
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• pp.85-97
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• 1974

In order to clarify the inducing conditions and cause of sterility in rice plants, 4 varieties were cooled at 3 different levels of temperature combined with 3 different levels of treatment period. And 19 varieties were tested to examine the varietal difference of cold resistance. The results obtained were summarized as follows; 1. There were significant varietal differences in the effect of cooling treatment at meiotic stage. Suwon 213-1 was induced heavy sterility by 3 day cooling treatment at 17.5$^{\circ}C$ whereas Hayayuki, Nongpaik and Jinheung were induced a little sterility by 3 day cooling treatment at 15$^{\circ}C$ and 5 day treatment at 17.5$^{\circ}C$. The per cent of grain fertility was correlated significantly with the delayed days to heading, the degree of panicle extraction (Suwon 213-1, Nongpaik, Jinheung), culm length (Nongpaik, Suwon 213-1), and Auricle distance (Suwon 213-1). The degree of sterility was able to be estimated from the linear regression equation between the degree of panicle extraction (distance from panicle neck to flag leaf) and fertility percentage. In the case of heavy cold damage by the treatment of low temperature at meiotic stage, the rice plant had somewhat lower pollen density per anther, small and ununiform anther and pollen in size, and more sterile pollen grains. Suwon 213-1 showed anthesis in almost all spikelets, while Nongpaik, Jinheung and Hayayuki indicated considerable number of indehisced anther at 5 days after heading. 2. The fertility were not generally higher in cooling treatment at heading stage than at meiotic stage treatment. And significant correlation was found between the percentage of grain fertility treated at above two stages. Nongpaik and Jinheung were not affected in percentage of fertility by 5 day treatment at 15$^{\circ}C$ when these were treated at heading stage. Indehisced anthers were not found in Suwon 213-1 and Hayayuki, but Nongpaik and Jinheung showed more anthers which did not show anthesis 3. There was different varietal response to low temperature which was indicated by the decrease of grain fertility resulted from cooling treatment at meiotic stage. Jaekeun and Jinheung did not show low fertility but Milseong, Suwon 210, Satominoli and Suwon 213-1 showed outstanding decrease in fertility percentage by the cooling treatment at meiotic stage. The varieties which had low fertility were likely to have low pollen density per anther, abnormal anthers, small size po]]en grains and many sterile pollens. 4. Remarkable varietal difference of cold resistance was found in heading stage cooling treatment. Nongpaik, Jinheung, Jaekeun, Paltal, Akibare, Milseung and Palkeong were not affected in grain fertility by cooling treatments but Nonglimna No. 1, Suseong, Hayayuki, Suwon 213-1 and Suwon 210 showed significantly high sterility as treated by cool temperature. Most of the varieties showed higher fertility by cooling treatment at heading stage than meiotic stage but Hayayuki, Suseong and Nonglimna No.1 showed lower fertility when these were treated at heading stage than meiotic stage. There were two grops of varieties in the response to cooling treatment, one was somewhat non-anthesised and the other showed full anthesis. 5. In cold injury test of young seedlings, the result of observation was not accorded with the degree of growth inhibition. As a general, Palkeum and Suseong were highly torelant to cool temperature but Suwon 213-1, Jaekeun, Paltal, Shirogane, Palkeong, Mankyung were highly susceptible. 6. There is no significant correlation between the degree of young seedling cold damage and or the degree of growth retardation at seedling stage and grain fertility resulted from coding treatment both heading and meiotic stage.

• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.10-20
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• 1977

An expriment was conducted to determine the rate of germination under low temperature and effects of low temperature on seedling of varieties derived from the cross between Indica and Japonica type of rice. Total of 30 varieties including leading variety, Tongil, were germinated at the temperature of $10^{\circ}C$. and $15^{\circ}C$. to determine the rate of germination, and six varieties also including Tongil were planted in pot, and seedlings were exposed to the temperature of $5^{\circ}C$. and $1^{\circ}C$. for 15 days and damage of plant growth due to low temperature was observed. 1. Under the condition of $10^{\circ}C$., varieties such as Iri #323, Suwon #253, Iri #325, Milyang #22, Suwon #251, and Suwon #267 were showing over 70 percent of germination ratio, while varieties, Dodolokiwase, Milyang #23, Yusin, Iri #328, and Iri #329 were below 10 percent in germination ratio. 2. Under the condition of $15^{\circ}C$., variety Suwon #262 was shown 100 percent of germination and varieties such as Milyg an#22, Dodlokiwase, Tongil, Milyang #29, Suwon #258, Milyang #23, Milyang #24, Milyang #28 and Milyang #21 were over 90 percent in germination ratio. However, varieties such as Iri #328, Iri #329, Jinheung, and Minehikari were below 50 percent in germination rate. 3. Considering the germination rate and average days required to germination, Milyang #22 and Iri #323 were highly resistant varieties to low temperature. The rate of germination of varieties from the cross between Indica and Japonica under low temperature was not always lower than that of varieties from Japonica type of rice. 4. Most of the seedlings of varieties used were quite resistant to $1^{\circ}C$. at least for six hours. However, leaves of rice were exposed to the the temperature of $1^{\circ}C$. for 12 hours, and the withered leaves were recovered soon when put in under normal temperature. The degree of leaf withering under low temperature was lower in Milyang #15, Japonica type than in varietieties belonging to $Indica{\times}Japonica$ type of rice. 5. When the seedlings of varieties such as Josaengtongil, Tongil and Yusin were exposed to the temperature of $1^{\circ}C$. for 36 hours, 70 percent of leaves were withered and when the time of expose were doubled, the leaves were completely died. When the temperature was fluctuated, over 75 percent of leaves were died, while 65 percent of leaves of Milyang #15 were died when exposed to $1^{\circ}C$, for 72 hours. 6. Significant growth retardation was observed for all entries when exposed to $1^{\circ}C$. for 24 to 36 hours. The growth retardation was apparently increased as the time of expose was extended.