• Weed & Turfgrass Science
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• v.3 no.2
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• pp.86-94
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• 2014

Survey was carried out in paddy fields to investigate the dominance of weed species and weed occurrence on 200 fields of southern Gyeonggi region in Korea during the year 2013. We observed 3 species of grass, 5 species of sedge, and 11 species of broadleaf and other weeds. The most dominant weed species was Eleocharis kuroguwai, followed by Echinochloa crus-galli, Sagittaria trifolia, Monochoria vaginalis, Scirpus juncoides and Bidens tripartita. The dominance value of E. kuroguwai and B. tripartita decreased compared to the survey results performed in 2005 but that of M. vaginalis, S. juncoides, S. trifolia and E. crus-galli increased. Weed occurrence increased from 2.83 g in 2005 to 3.51 g in 2013 based on weed dry weight per $m^2$. Occurrence ratio of annual weeds to perennial weeds changed from 45.2% : 54.8% in 2005 to 45.8% : 54.2% in 2013. If we analyze dominance of weed species based on the rice transplanting timing, E. kuroguwai and E. crus-galli were the most dominant weed species at mid-May transplanting, and M. vaginalis and S. juncoides were the most dominant weed species at late- May transplanting, and M. vaginalis and E. kuroguwai were the most dominant weed species at early-June transplanting. Since paddy weeds resistant to sulfonylurea herbicides are expected to be continuously increased, the regular monitoring of their occurrence and efficient control methods should be considered in future.

• Journal of the Korean association of regional geographers
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• v.6 no.3
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• pp.1-36
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• 2000

Periodic markets of the later Choson dynasty had undergone fundamental changes during the late Chosun dynasty and Japanese colony period. This paper aims to analyse the spatial distributions and changes of the periodic markets in the middle stream of Han-River in this era in the use of the survey of documentary records and fieldwork. Before the early 1910s, long distance transportation was made by riverboats, short distance transportation was done by porters and pack animals. Because goods such as rice, soybean and salt were very heavy and needed long distance transport, they were mainly transported by riverboats. Accordingly, riverports on the shore of river played important roles in exporting and importing goods as nodes of long distance transportation. The opening of railroad Seoul-Busan, the construction of new roads(Sinjakno) of 1910s and the use of oxcarts produced striking changes in the spatial distribution and hierarchy structure of periodic markets. These changes also had influence on the outflow and inflow of goods in the middle stream of Han-River. In the parr of outflow of goods, it seems that the line linking Icheon city-Yongin city-Anseong city played a role in making the boundaries of the marketing areas between goods trams ported by the rail road Seoul-Busan and goods done by Han River river boats. Anseong, Osan and Suwon periodic markets located around railroad stations occupied the higher positions than those of other regions in the hierarchial structure of periodic markets. Their marketing areas could nearly overwhelm those of riverports located in the middle stream region of Han River and extend to the middle stream region of Han River as a result of decrease of transport cost through using of oxcarts and railroads. the opening of railroad Suwon-Yeoju(Suryoson) and railroad Cheonan-Janghawon(Cheonjangson) brought about changes of the structure of long distance trade again. In a part of outflow of goods, it seems that as a result of the new opening of their railroads periodic markets around railroads seized a large portion of the marketing area of the southern part of Yoju and Ichon area and therefore made extreme change in rivershipping of Han River. In the inflow part of goods, goods transported by riverboats from the downstream of Han River before the opening of railroad were imported directly from railroad stations. Accordingly, rivershipping and riverports declined. And because goods were imported by way of great periodic markets and supplied to small periodic markets and consumers before the opening of railroad, but supplied from railroad stations to small periodic markets and consumers after the opening of railroad. The volume of turnover of such great periodic markets as Anseong, Osan and Suwon periodic markets therefore declined. On the other hand, because Yangpyong area had not been yet included within the sphere of influence of railroad until 1930s, it heavily depended on rivershipping of Han River as before. But the opening of railroad Seoul-Wonju(jungangson) brought about decline of rivershipping in Yangpyong and Wonju area.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.4
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• pp.307-312
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• 2009

This experiment was conducted to compare the agronomic characteristics and productivity of induced annual legumes at paddy field of Cheonan and Naju from 2004 to 2006. Chinese milk vetch (wild type), crimson clover (C.V. Linkarus), forage pea (C.V. Austrian pea), hairy vetch (C.V. Oregon commen) were used in this study. At the Naju region, the earliest flowering on 2nd may was found in Chinese milk vetch, while the latest on 18th May in forage pea. Fresh, dry matter (DM) and crude protein (CP) yields of crimson clover were highest as 28,870, 6,986 and 943 kg/ha, respectively. but the yield of chinese milk vetch was low by 9,885, 1,749 and 338 kg/ha. At the Cheonan region, the most fast flowering date variety was Chinese milk vetch, hairy vetch was very late as 19th May. Fresh, DM and CP yields of hairy vetch were highest as 7,916, 1,141 and 113 kg/ha, respectively. but the yield of chinese milk vetch showed the lowest by 270, 42 and 8 kg/ha. The CP content of annual legumes was 14.3%. chinese milk vetch showed the highest CP content by 19.3% and hairy vetch showed the lowest content by 9.9%. The present data showed that the productivity was closely dependent on winter hardness, in conclusion, crimson clover at Naju and hairy vetch at Cheonan region was suggested to be the most proper species as winter crop after rice harvest on paddy field when considered the winter hardiness.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.2
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• pp.79-88
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• 2022

This study was conducted to evaluate the productivity of whole crop silage wheat utilizing the paddy fields during a couple of years from 2019 to 2021 in Suwon, Korea. This investigation was used the two maturity types of wheat cultivar 'Cheongwoo' (early) and 'Taeu' (late). The heading date of 2^nd year (Oct. 2020 to May. 2021) cultivation was delayed about 11 to 13 days by more than 1^st year (Oct. 2019 to May. 2020). The growth characteristics were shown that the plant height was increased in 2^nd cultivation, while the number of culms and the panicle part ratio were decreased. Moreover, the nutritive value of 'Cheongwoo' and 'Taeu' were also decreased in 2^nd cultivation. These changes have thought to a difference of the precipitation by cultivation years. Because, the precipitation during the period from the end of winter dormancy to the harvesting stage in 2^nd (337 mm) cultivation was more about twice than 1st (169.3 mm) cultivation. However, the dry matter yield of 'Cheongwoo' was not shown a statistical difference by cultivation years, while 'Taeu' was shown to decrease tendency. The total dry matter yield regardless of the cultivation years were higher in 'Cheongwoo' than 'Taeu', and especially 'Cheongwoo' was more 3 tons per hectare (15.3 t/ha) than 'Taeu' (12.6 t/ha) at 2^nd cultivation (p<0.01). The trend of dry weight in 'Cheongwoo', early mature type, showed a relatively high ratio of dry matter (p<0.05) was considered that due to a high panicle ratio by a fast heading and an adequate weight of panicles by a sufficient maturing. In conclusion, selecting the early maturity cultivars could achieve a higher and more stable total dry matter yield considering the cropping system in the central region. Furthermore, it also has the advantage of being able to double-cropping system with forage rice, which has considered the maximum whole-crop forage production year-round. These results suggest that the 'Cheongwoo' be optimum cultivar to produce the year-round forage on paddy fields in the central region.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.1
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• pp.20-27
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• 1983

A series of laboratory experiment was conducted to find out the chemical composition, characterization of humic substances by physical and chemical methods and reaction of Na-pyrophosphate, $Ca(OH)_2$ and rice straw with albumin on the degradation of soil organic matter in the volcanic ask soils of the Jeju Island. Results obtained were summarized as follows: 1. The contents of organic matter, available silicon, active iron and aluminum concentration in volcanic ash the soils were remarkably higher but available phosphorous was comparatively lower than the mineral soils. In volcanic ash soil, the contents of potassium, calcium and magnessium were higher in upland soil than that of forest soil. The ratios of active $Al^{{+}{+}{+}}/Fe^{{+}{+}}$, C/P and $K/Ca^+$ Mg were apparently high in volcanic ash soils while that of $SiO_2$/O.M. was high in mineral soil. 2. The carbon/nitrogen ratio in humin, humic acid content in organic matter, and carbon contents of humin in total carbon of soil organic matter were apparently higher in the volcanic ash soils than in the mineral soils, The total nitrogen and fractions of acid or alkali soluble nitrogen were remarkably high in volcanic ash soils while mineralizable nitrogen ($NH_4$-N and $NO_3$) contents were high in mineral soils. 3. The values of K600, RF and log K were also higher in volcanic ash soils than those in mineral soils, and the absorbance in the visible range were high and color was dark in the soil of which humification was progressed Extracted humic acid from volcanic ash soil was less reactive to the oxidizing chemical reagent and was persistance to the acid or alkali hydrolysises. 4. The major oxygen-containing functional groups in humic substances of volcanic ash soils were phenolic-OH alcoholic-OH and carboxyl groups while those in mineral soil were methoxyl and carbonyl groups. 5. Absorption spectra of alkaline solution of humic acid ranged from 200 nm to maxima 500 nm. Visible spectra peaks of from humic substances in the visible region were recognized at 350, 420, 450 and 480 nm. Only one single absorbance peak was observed in the visible region at 362 nm for Heugag series and two absorbance Peak were also at 360 nm and 390 nm for Yeungrag series. 6. Evolution of carbon as $Co_2$ was increased with addition of Na-pyrophosphate in Namweon and Heugag series, and "priming effects" took place on the soil organic matter decomposition by addition of rice straw with albumin in Ido series.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.659-666
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• 2005

The purpose of this study was to compare the intake status of calcium, phosphorus, iron, and zinc of Korean adults residing in different regions. Subjects were recruited and divided into three groups according to the districts where they lived, which included rural (n=137), coastal (n=100), and urban district (n=117). Subjects were interviewed using a general questionnaire and 24-hour recall method for dietary intake. The average age of the subjects were 58.1 years for rural district, 57.7 years for coastal district, and 48.6 years for urban district. There was no significance in total food intake by regions. The food intakes from cereals, mushrooms, vegetables of rural district, that from fishes of coastal district, and those from sugars, milks, oils of urban area were the highest among three districts. The calcium, phosphorus, iron, and zinc intakes were $60.1\%,\;123.9\%,\;95.2\%,\;and\;73.1\%$ of RDAs, respectively. The calcium intakes as percentage of RDA in rural and coastal district were significantly (p<0.01) lower than that in urban district. A larger number of subjects from coastal or urban district ate under $75\%$ of zinc RDA compared to those from rural village. Major sources of dietary calcium in total subjects were anchovy, kimchi, milk, soybean curd, rice, ice cream, sea mustard, yogurt, loach, and welsh onion. Rice supplied $15.5\%$ for phosphorus, $22.1\%$ for iron, and $35.9\%$ for zinc of total intake. Except for rice, major sources of dietary zinc were pork, beef, small red bean, dog meat, chicken, jacopever, soybean curd, glutinous millet, and kimchi. In conclusion, the food and mineral intakes of adults differed according to the regions in which they resided. The food and nutrient intakes of coastal district were not satisfactory, and calcium and zinc intakes of three regions did not meet RDAs. Therefore, it is required unique and discriminatory nutritional education with each region for increasing intakes of calcium and zinc.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1472-1481
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• 2007

The purposes of the study were to find refined taste of ancestor through historical research about traditional cooking method and ingredient for the purpose of enriching today#s dietary life and to hand down a particular style of regional dish and excellence of nutritional aspect by providing a standard recipe and nutrition analysis data on #Dong-rae Pajeon#. To collect data about traditional ingredients and cooking method, researcher interviewed seven local natives who have kept a traditional food costumes, visited four restaurants, and reviewed ten cookbooks. The interviewees recalled and demonstrated the cooking procedure. The standard recipe of #Dong-rae Pajeon# was created after three experimental cookings, based on the recipes of the natives, restaurants, and cookbooks. According to the natives# statements, #Dong-rae Pajeon# was a special dish that was offered to the king at #Samzi-nal# (March 3rd of the lunar calendar). It was also a seasonal (before cherry blooming time) and memorial service dish of the province#s high society. The main ingredients were small green onion, dropwort, beef, seafood (large clam, mussel, clam meat, oyster, shrimp, fresh water conch), waxy rice powder, non-wax rice powder, and sesame oil which were abundant in Busan and Kijang region. Energy per 100 g of #Dong-rae Pajeon# was 148 kcal. Protein, lipid, fiber, Ca, and Fe contents were 8.8 g, 2.0 g, 8.6 g, 57.7 mg, and 1.8 mg respectively. Contents of cystine, lysine, leucine, valine, isoleucine which are essential amino acids were high in #Dong-rae Pajeon#. Fatty acids contents are oleic acid (20.5%), linoleic acid (20.1%) and linolenic acid (10.4%) while P/M/S ratio was 0.73/0.67/1.

• Korean Journal of Environmental Agriculture
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• v.32 no.1
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• pp.24-34
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• 2013

BACKGROUND: This study was carried out to compare population size of mudfish (Misgurnus mizolepis) between the agricultural practices and to investigate the causes of its differences. We also provided basic information for sustainable use of mudfish population in paddy fields. METHODS AND RESULTS: Mudfish and benthic invertebrates which are diet of mudifish were investigated from 8 sites of organic and conventional rice paddy fields in South Korea. Total number of mudfish were 1,882 individuals in survey sites. Mudfish population were 2.4 times larger in organic paddy fields (1,333 individuals) than in conventional paddy fields (549 individuals). The population size of mudfish was larger in Mungyeong-si, Gyeongsangbuk-do and Anseong-si, Gyeonggi-do with relatively better environmental conditions than the other 5 sites including Suwon-si, Gyeonggi-do, Cheongyang-gun, Chungcheongnam-do, Gunsan-si, Jeollabuk-do, Gimje-si, Jeollabuk-do, Hwasun-gun, Jeollanam-do, Hamyang-gun, Gyeongsangnam-do. Benthic invertebrates collected from survey sites were 74 species, 68 genera, 46 families, 19 orders, 6 classes and 3 phyla. According to agricultural practices, benthic invertebrates were identified 66 species, 62 genera, 41 families, 17 orders, 6 classes and 3 phyla in organic paddy fields while there were 66 species, 60 genera, 42 families, 18 orders, 6 classes and 3 phyla in conventional paddy fields. Dominant invertebrates were Chironomidae sp., Branchiopoda sp., Ostracoda sp., and Copepoda sp. There were no differences in dominant species between organic and conventional paddy fields. Population size of mudfish tended to increase with the population size of Chironomidae sp., Branchiopoda sp., Ostracoda sp., and Copepoda sp. But, only population of Chironomidae sp. and Copepoda sp. statistically related to population size of mudfish. The number of individuals of mudfish (Misgurnus mizolepis) was higher at the low rate of urban area than any other surveyed region and was affected by appearance ratio of main preys such as Chironomidae sp. and Ostracoda sp. CONCLUSION(S): The population size of mudfish in rice paddy fields could be affected by environmental conditions and agricultural practices such as organic and conventional methods.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.314-326
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• 2020

This study was carried out to develop a resistant variety against the K3a race of bacterial blight, Xanthomonas oryzae pv. oryzae, through expansion and pyramiding of resistance genes. To develop an elite bacterial blight-resistant cultivar, the breeding process and bacterial blight resistance reactions in advanced backcross lines (ABLs) were analyzed. ABLs21 which contain Xa3 and Xa21, were developed by double backcrossing japonica cultivar Hwanggeumnuri, which has bacterial blight resistant Xa3 gene, and indica variety IRBB21, which havs Xa21 gene, followed by disease resistance bioassay and marker-assisted selection. The resistance genes of ABLs21 were amplified by PCR with the molecular markers 9643.T4 (Xa3) and U1/I1 (Xa21). Hwanggeumnuri and IRBB3 showed resistance reactions against K1, K2, and K3 races, and a susceptible reaction against K3a, K4, and K5 races. IRBB21 showed resistance reactions against K2, K3, K3a, K4 and K5 races, and a susceptible reaction against K1 race. Hwanggeumnuri showed susceptible reactions at the seedling, tillering and adult stages (all stages), whereas ABL21-1 showed moderate resistance at the tillering stage. ABL21-1 showed stable resistance against 18 isolates of K3a race, and the lesion length was shorter than that of the donor parents. In cluster analysis, the HB4032 isolate showed the highest pathogenicity among the 18 isolates. The molecular marker polymorphisms and average substituted chromosome segment lengths of ABLs21 were 63.2 % and 86.1 cM, respectively. Insertion of the donor chromosomal segments occurred in the predicted region of the Xa21 gene of ABLs21.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.3
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• pp.187-196
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• 2009

The objectives of this study were to evaluate the different cutting dates on the changes of feed quality among five cereals (barley, wheat, rye, triticale and oat) for whole crop silage. Field trials were conducted at paddy field in Yesan, Chungnam Province and the aerial parts were clipped 10 days from 15 March to 15 June. Changes of acid detergent fiber (ADF) content in relation to different cutting dates was described by a quadratic curve for 5 winter cereals crops. ADF content reached a maximum at 5 days after heading in barley cultivar 'Youngyang', 7 days in wheat 'Keumkang', 18 days in rye 'Gogu', 1 days in triticale 'Shinyoung' and 10 days in oat 'Samhan'. Neutral detergent fiber (NDF) content were linearly increased as growing after overwintering and stagnated or slightly decreased after heading. The crude protein were linearly decreased throughout the growth period of 5 whole crop cereals. Digestible dry matter (DDM) content were decreased from early stages to heading and subsequently increased as grain filling. Relative feed value (RFV) for 5 crops were decreased as growing and subsequently increased as grain filling after heading. Barley cultivar for only forage use 'Youngyang' were lower at ADF and NDF content and higher at DDM and RFV after heading than those of other cereals for forage use. So, barley for whole crop silage was a good crop with high feed quality and high proportion of spikes compared with other winter cereal crops. Wheat cultivar for grain 'Keumkang' were higher at crude protein than those of other four cereals from overwintering to maturing and were higher at DDM and RFV after heading than those of rye, triticale and oat. Rye cultivar with cold tolerant and high fresh yielding 'Gogu' were highest at ADF and NDF content and lowest at DDM content and RFV. So, rye was a crop with low quality for forage use compared to other winter cereal crops. Triticale cultivar with flourishing and high yielding 'Shinyoung' was intermediated between barley and rye, and were linearly increased at DDM yield by different cutting dates. Oat cultivar with cold tolerant and high tillering 'Samhan' were lower at ADF and NDF content and higher at crude protein before heading, but after heading, there are not especially advantages compared to barley, wheat or triticale.