• Title/Summary/Keyword: 월동지

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Surgical Experience of Open Heart Surgery in Neonates (신생아개심술의 외과적 경험)

  • 이용훈;조은희
    • Journal of Chest Surgery
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    • v.29 no.8
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    • pp.828-835
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    • 1996
  • From January 1993 to April 1995, 27 neonates (under age of 30 days underwent open heart surgery in the Department of Thoracic and Cardiovascular Surgery, Dong-A Medical Center. Mean age and weight were 12.1 days(2days∼306ays) and 3.29 kg(2.6kg∼4.1 kg) respectively. Cardiac anomalies were simple complete transposition of great arteries(TGA) in 11 neonates, TGA with coarctation of aorta(COA) in 1 , total anomalous pulmonary venous connection(TAPVC) in 5, double inlet right ventricle with TAPVC in 1, interrupted aortic arch(IAA) with ventricular septal defect(VSD) in 3, pulmonary atresia(PA) with intact ventricular septum(IVS) in 3, pulmonary stenosis with IVS in 1, Taussig-Bing anomaly with IAA in 1, and hypoplastic left heart syndrome(HLHS) in 1 . Postoperative complications were myocardial and/or pulmonary edema which caused open sternum in 13 patients(54.2%), acute renal failure( RF) in 10(37.0%), Intractable low cardiac output syndrome (LCOS) including weaning failure from cardiopulmonary bypass in 7(25.9%), bronchopulmonary dysplasia in 1, wound infection in 1, and paroxysmal supraventricular tachycardia in 1. Nine of 13 patients with postoperative open sternum were recovered with delayed sternal closure, and seven of 10 patients survived postoperative ARF with peritoneal dialysis. There were 8 operative deaths(29.6%): 3 in the patients with simple complete TGA, 1 In TCA with COA, 1 in PA with IVS, 1 in Taussig-Bing anomaly with IAA, 1 in DIRV with TAPVC, and 1 in HLHS. One late death occurred after arterial switch operation in simple TGA. The mosts common cause of death was low cardiac output syndrome. Our initial experience of open heart surgery in neonates showed high operative mortality and morbidity, especially in complex anomalies.

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Differential Susceptibility to High Temperature and Variation of Seasonal Occurrence between Spodoptera exigua and Plutella xylostella (파밤나방과 배추좀나방의 고온 감수성 차이와 연중 발생 변이)

  • Kim, Minhyun;Lee, Seunghee;Kim, Yonggyun
    • Korean journal of applied entomology
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    • v.55 no.1
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    • pp.17-26
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    • 2016
  • Climate change has been regarded as one of main factors to change Korean insect pest fauna. Especially, a global warming model predicts to expand habitat for insect pests originated from tropical or subtropical regions. Two insect pests, the beet armyworm (Spodoptera exigua) and the diamondback moth (Plutella xylostella), are known to overwinter in some greenhouse conditions without diapause induction in Korea. There was a clear difference between these two insects in seasonal occurrence. P. xylostella occurred only at early spring and fall seasons, but did not occur during summer. In contrast, S. exigua maintained their occurrence from late spring to fall seasons. This study set up a hypothesis that the difference in the seasonal occurrence may be resulted from variation in susceptibility to high temperature. To test the hypothesis, heat tolerance was compared between these two insects. Exposure to $42^{\circ}C$ for 40 min killed 100% individuals of P. xylostella larvae. However, most larvae of S. exigua survived in response to $42^{\circ}C$ even for 80 min. Heat tolerance varied among developmental stages in both insects. Highest tolerant stages were $4^{th}$ instar larvae and adults for P. xylostella, but $1^{st}$ instar larvae for S. exigua. Pre-exposure to $37^{\circ}C$ for 30 min significantly increased heat tolerance in both insects. Induction of heat tolerance accompanied with significant increase of glycerol contents in the hemolymph in both insects and up-regulation of three heat shock protein expressions in S. exigua. These results suggest that the differential susceptibility to high temperature explains the disappearance of P. xylostella during summer, at which S. exigua maintains its occurrence.

Effects of Various Vernalization Duration and Growth Habit on Ear Primordium Development and Heading Date in Barley (보리의 파성정도가 유수분화 및 출수기에 미치는 영향)

  • Chun, Jung-Un;Huh, Sang-Man;Lee, Eun-Sup
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.32 no.3
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    • pp.341-346
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    • 1987
  • Seven barley varieties were tested under three different vernalization durations for observing the effects of vernalization duration and different growth habit on shoot apex development and heading date. The final leaf number per main stem in 3 and 6 weeks vernalized seedlings did not vary among varieties, but ranged 7 to 14 leaves in non-vernalized seedlings. The winter types had more leaves than the spring types. Days for each leaf emergence in non-vernalization were retarded 1. 3 to 1. 5 days in comparison with 3 or 6 weeks vernalized seedlings. In general, the leaf emergence speed of spring types was faster than that of winter types. The VI stage whose double ridge formed, did not vary in 6 weeks vernalization, but spring (Gangbori & Dongbori 2) and facultative or winter types showed two conspicuous difference patterns. The differences of days to X stage were great among different vernalization duration and varieties; the stage of spring types was reached faster than that of winter types. The early varieties within the same growth habit were reached to X stage faster, and the time of flag leaf emergence showed the similar tendency to the differentiation of X stage. The time of the first rapid stem internode elongation became late as for incompletely vernalized seedlings. The time within the same vernalization duration became later in winter types than in spring types, and even within the same growth habit, the time of early varieties became faster than that of late varieties. The growth habit in especially non-vernalized seedlings had highly significant correlation coefficients with the times of leaf development speed, leaf number per main stem, the first rapid stem internode and young spike elongations, X stage, and flag leaf emergence. However, the relationship between growth habit and time of heading in the field was not close.

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Growth Characteristics, Seed and Forage Productivity of New Naked Oat (Avena nuda L.) Cultivar "Jungmo2005" (귀리 품종 '중모2005'의 생육특성과 종실 및 조사료 생산성)

  • Han, Ouk-Kyu;Park, Tae-Il;Park, Hyung-Ho;Park, Ki-Hun;Oh, Young-Jin;Ku, Ja-Hwan;Kweon, Soon-Jong;Ahn, Jong-Woong
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.37 no.1
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    • pp.28-34
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    • 2017
  • A new naked oat cultivar, 'Jungmo2005'(Avena nuda L.), was developed for food and forage use by National Institute of Crop Science, RDA in 2010. It was derived from a cross between $F_1$['Early80'/'Gwiri33'] and $F_1$['Early80'/'Gwiri23']. 'Early80', a covered oats, has early heading and high yielding, while 'Gwiri23' of covered type and 'Gwiri33' of naked type has early heading with large-size grain. 'Jungmo2005' has the characteristics of narrow and long leaves of pale green color, middle diameter culm of yellow color and medium grain of whitish yellow color. Cultivar 'Jungmo2005' had 2 days earlier heading date (May 9) than the check cultivar 'Seonyang' (May 11) in field condition. The 'Jungmo2005' showed better winter hardiness than that of the check cultivar, and similar to the check cultivar in respect to lodging resistance. The 'Jungmo2005' had 105 cm of culm length, 21.5 cm of spike length, 658 spikes per $m^2$, 82 grains per spike, 23.3 g of 1,000-grain weight, and 622 g of test weight. The grain yield of 'Jungmo2005' was averaged $3.38MT\;ha^{-1}$, which was 6% higher than that of the check. Average forage fresh and dry matter yield of 'Jungmo2005' harvested at milk-ripe stage were 44.8 and $12.6tone\;ha^{-1}$, respectively, compared with 47.5 and $12.5tone\;ha^{-1}$ of the check. The protein content of the 'Jungmo2005' was similar to the check (7.6% and 7.5%, respectively), while ADF (28.6%) and NDF (51.5%) were lower than the check (31.4% and 57.0%, respectively). TDN content and RFV were higher than those of the check (66.3%, 120.3 and 64.1, 105.2, respectively). 'Jungmo2005' is recommended for fall sowing cropping only in the south area where daily minimum mean temperatures are averaged higher than $-4^{\circ}C$ in January, and it should not be cultivated in mountain areas, where frost damages is likely to occur. The areas would do better only to sow in spring season.

The Effects of Grass Seed Mixtures using Domestic Cultivars on Botanical Composition and Dry Matter Productivity in Low Productive Hilly Pasture, Central Region of Korea (중부지역 부실 산지초지에서 국내육성 신품종 목초 이용 혼파조합이 식생구성 및 건물생산성에 미치는 영향)

  • Jung, Jeong Sung;Kim, Jong Geun;Kim, Hyeon Shup;Park, Hyung Soo;Choi, Ki Choon;Lee, Sang Hoon;Ji, Hee Jung;Choi, Gi Jun;Kim, Won Ho
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.37 no.2
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    • pp.132-139
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    • 2017
  • This study was conducted to find out the effects of over seeding using new grass varieties orchardgrass 'Kordione' and 'Onnuri', and tall fescue 'Greenmaster' on botanical composition and dry matter productivity from 2013 to 2016 in low productivity hilly pasture, middle area of Korea. There were used 3 grass seed mixture types made of different compositions and amounts {T1: control - no over seeding, T2: tall fescue (TF) 'Greenmaster' $18kg\;ha^{-1}$, orchardgrass (OG) 'Kordione' $9kg\;ha^{-1}$, Perennial ryegrass (PRG) 'Linn' $5kg\;ha^{-1}$, and Kentucky bluegrass (KBG) 'Kenblue' $2kg\;ha^{-1}$, T3: TF 'Greenmaster' $9kg\;ha^{-1}$, OG 'Kordione' $18kg\;ha^{-1}$, PRG 'Linn' $5kg\;ha^{-1}$, and KBG ' Kenblue' $2kg\;ha^{-1}$, T4: TF 'Greenmaster' $9kg\;ha^{-1}$, OG 'Onnuri' $18kg\;ha^{-1}$, PRG 'Linn' $5kg\;ha^{-1}$, and KBG 'Kenblue' $2kg\;ha^{-1}$}. In the botanical composition of grassland, T1 nearly remained constant in other seasons while ratio of weeds were increased in summer season. T2 was better than control (T1) in portion of grass ratio, which has increased by 80%. In the early time of establishment, the portions of OG were increased in T2, but TF rate was increased after 3 years later when grass was established. T3 and T4 showed a very similar patterns, grass ratio had increased by 80% and the portion of KBG had increased as time passed. T2 ($129,763kg\;ha^{-1}$) was showed the highest dry matter yield than other treatments (T1: $6,756kg\;ha^{-1}$, T3: 9641, and T4: 10,738) in 2016.

The Suitable Region and Site for 'Fuji' Apple Under the Projected Climate in South Korea (미래 시나리오 기후조건하에서의 사과 '후지' 품종 재배적지 탐색)

  • Kim, Soo-Ock;Chung, U-Ran;Kim, Seung-Heui;Choi, In-Myung;Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.11 no.4
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    • pp.162-173
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    • 2009
  • Information on the expected geographical shift of suitable zones for growing crops under future climate is a starting point of adaptation planning in agriculture and is attracting much concern from policy makers as well as researchers. Few practical schemes have been developed, however, because of the difficulty in implementing the site-selection concept at an analytical level. In this study, we suggest site-selection criteria for quality Fuji apple production and integrate geospatial data and information available in public domains (e.g., digital elevation model, digital soil maps, digital climate maps, and predictive models for agroclimate and fruit quality) to implement this concept on a GIS platform. Primary criterion for selecting sites suitable for Fuji apple production includes land cover, topography, and soil texture. When the primary criterion is satisfied, climatic conditions such as the length of frost free season, freezing risk during the overwintering period, and the late frost risk in spring are tested as the secondary criterion. Finally, the third criterion checks for fruit quality such as color and shape. Land attributes related to these factors in each criterion were implemented in ArcGIS environment as relevant raster layers for spatial analysis, and retrieval procedures were automated by writing programs compatible with ArcGIS. This scheme was applied to the A1B projected climates for South Korea in the future normal years (2011-2040, 2041-2070, and 2071-2100) as well as the current climate condition observed in 1971-2000 for selecting the sites suitable for quality Fuji apple production in each period. Results showed that this scheme can figure out the geographical shift of suitable zones at landscape scales as well as the latitudinal shift of northern limit for cultivation at national or regional scales.

Ecological variation between two populations of Thecodiplosis japonensis uchida et Inouye in Korea (솔잎혹파리 두 집단간(集團間)의 생태변이(生態變異))

  • Hwang, Yu Chul;Yim, Kyong Bin
    • Journal of Korean Society of Forest Science
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    • v.79 no.2
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    • pp.115-126
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    • 1990
  • This study was performed to find differences in phototaxis response of the larva, adult emergence, sex ratio and gall formation rate of Thecodiplosis japonensis Uchida et Inouye between two areas, north and south. Larvae from these two areas, Hweng-sung in north and Moo-an in south, both considered to be the sities of severe outbreak of the insect recently, were collected from the floor and transported to the entomology larboratory, Won-Kwang University in Iri, then overwintered. These larvae were used for various experimental purposes on various dates. The following results were obtained. 1. The sizes of larvae reached 2.45 in length, 0.70 in width for north, and 2.50 in length, 0.72 in width for sourth. It seems that the differents were not significant. 2. It is known that Leaving gall of larvae to the ground for the hibernation usually occurs on rainy days. For the larvae dispersion, the phototaxis response of the larvae was hypothesized. To check this, the author manipulated some different illumination intensities adjusting the distance between the glass tube in which 100 larvae were contained and electric bulb. The glass tubes were blackened all but except a small portion. The phototaxis responses between two areas seemed to be different particularly at low light intensities, 45, 145 and 1000 lux, The larvae from north assembled to the clear portion of the glass tube were more than 30 out of 100, however less than 30 in south sample regardless of the time passage. In either cases, the saturation points came after about 8 to 10 hours. If temperature units were used, the phototaxis curve= after 1 hour illumination between two areas provided significant differences. 3. The adult emergence of south area was lagged 10 days later than that of north area. The accumulated effective day-degrees of temperature for adult emergence were $934^{\circ}C$ for north area and $1180^{\circ}C$ for south area. The emerging duration of north area appeared to be in late May through the early of July and the peak emergence occurred in middle June that was approximately 15days earlier than that of south area. The sex ratio of female to male, regardless of area, was approximately 3 : 1. 4. The rates of gall formation of the red pine(Pinus densiflora Siebold et Zuccarini), 6-year-old seedlings, were as low as 9.94% for north area and 8.87% for south area. Through the close observation, the author presumed that the population reduction was greatly affected during the prepupa stage by relative moisture content and predators, such as spiders and ants presented on the ground.

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A Thermal Time-Driven Dormancy Index as a Complementary Criterion for Grape Vine Freeze Risk Evaluation (포도 동해위험 판정기준으로서 온도시간 기반의 휴면심도 이용)

  • Kwon, Eun-Young;Jung, Jea-Eun;Chung, U-Ran;Lee, Seung-Jong;Song, Gi-Cheol;Choi, Dong-Geun;Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.8 no.1
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    • pp.1-9
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    • 2006
  • Regardless of the recent observed warmer winters in Korea, more freeze injuries and associated economic losses are reported in fruit industry than ever before. Existing freeze-frost forecasting systems employ only daily minimum temperature for judging the potential damage on dormant flowering buds but cannot accommodate potential biological responses such as short-term acclimation of plants to severe weather episodes as well as annual variation in climate. We introduce 'dormancy depth', in addition to daily minimum temperature, as a complementary criterion for judging the potential damage of freezing temperatures on dormant flowering buds of grape vines. Dormancy depth can be estimated by a phonology model driven by daily maximum and minimum temperature and is expected to make a reasonable proxy for physiological tolerance of buds to low temperature. Dormancy depth at a selected site was estimated for a climatological normal year by this model, and we found a close similarity in time course change pattern between the estimated dormancy depth and the known cold tolerance of fruit trees. Inter-annual and spatial variation in dormancy depth were identified by this method, showing the feasibility of using dormancy depth as a proxy indicator for tolerance to low temperature during the winter season. The model was applied to 10 vineyards which were recently damaged by a cold spell, and a temperature-dormancy depth-freeze injury relationship was formulated into an exponential-saturation model which can be used for judging freeze risk under a given set of temperature and dormancy depth. Based on this model and the expected lowest temperature with a 10-year recurrence interval, a freeze risk probability map was produced for Hwaseong County, Korea. The results seemed to explain why the vineyards in the warmer part of Hwaseong County have been hit by more freeBe damage than those in the cooler part of the county. A dormancy depth-minimum temperature dual engine freeze warning system was designed for vineyards in major production counties in Korea by combining the site-specific dormancy depth and minimum temperature forecasts with the freeze risk model. In this system, daily accumulation of thermal time since last fall leads to the dormancy state (depth) for today. The regional minimum temperature forecast for tomorrow by the Korea Meteorological Administration is converted to the site specific forecast at a 30m resolution. These data are input to the freeze risk model and the percent damage probability is calculated for each grid cell and mapped for the entire county. Similar approaches may be used to develop freeze warning systems for other deciduous fruit trees.

A Study on Nutritive Values and Salt Contents of Commercially Prepared Take-Out Boxed-Lunch In Korea (한국형 시판 도시락의 영양가 및 식염함량)

  • Kim, Bok-Hee;Lee, Eun-Wha;Kim, Won-Kyung;Lee, Yoon-Na;Kwak, Chung-Shil;Mo, Sumi
    • Journal of Nutrition and Health
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    • v.24 no.3
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    • pp.230-242
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    • 1991
  • This research was conducted on the 10 take-out boxed-lunches commercially prepared in the department stores. chain stores. and the public railroad trains in Korea. Sampling was conducted from February 1990 to March 1990. Nutritive values and sodium contents of the 10 boxed-lunch samples are summarized as follows : 1) The average weight(percentage) of the cooked rice and the side dishes were 304.6g(49.4) and 312.4(506%), respectively. The weight of these samples were significantly heavier than that of Japanese style boxed-lunches. 2) The average number of the side dishes was 12. The average numbers of food items classified by the five food groups were 6.1 in protein food group, 0.3 in calcium food group. 6.0 in vitamin and mineral food group. 1.5 in carbohydrate food group, and 1.5 in oil and fat food group. 3) They contained on the average 840.7kcal of energy, 38.9g of protein, 22.7g of fat, 120.4g of carbohydrate. 300.8mg of calcium. 410.8mg of phosphours, 6.61 mg of iron. 219.8 R.E. of vitamin A, 0.46mg of thiamin, 0.67mg of riboflavin, 10.5mg of niacin, 27.5mg of ascorbic acid. Thus. except vitamin t the content of all the nutrients were higher than the value of 1/3 of the RDA for adults. 4) The high priced group(group 2) had more protein, calcuim. iron and niacin contents than the cheaper group(group 1). Probably, it's because the group 2 had more animal foods than the group 1. 5) The average energy content per unit price(100 won) was 37.3kcal and the average protein content per unit price(100 won) was 1.64g. Korena style boxed-lunches had higher energy and protein contents per unit price than Japanese style, and the group 1 higher than the group 2. 6) The average energy Proportions of Protein, carbohydrate. and fat were 18.3%, 57.4%, and 24.3%, respectively. These proportions are good enough. 7) Frequency of cooking methods for the side dishes were found in the decreasing order : pan-frying, frying, braising, seasoning, kimchi, grilling, pickling, stir-frying, steaming and fermenting. Generally simple cooking methods were used, thus the menus were lack or varieties. 8) Frequency of colors for the side dishes were found in the decreasing order : red, brown. yellow, green, black, white. Too much red pepper was used. 9) The average capacity of the containers for the staples and the side dishes were 468.1ml and 590.6ml, respectively. And the containers could not keep the food items well seperated. 10) The average contensts of sodium and salt were 2.287mg and 5.76g, in the range of 1, 398mg to 3, 489mg and 3.53g to 8.80g, respectively. These are much higher values than the recommended amount of salt.

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Response of Potassium on Main Upland Crops (주요(主要) 전작물(田作物)에 대(對)한 가리성분(加里成分)의 비교(肥效))

  • Ryn, In Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.10 no.3
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    • pp.171-188
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    • 1977
  • The response and effect on main upland crops to potassium were discussed and summarized as follows. 1. Adequate average amounts of potash per 10a were 32kg for forage crop; 22.5kg for vegetable crops; 17.3kg for fruit trees; 13.3kg for potatoes; and 6.5kg for cereal crops. Demand of potassium fertilizer in the future will be increased by expanding the acreage of forage crops, vegetable crops and fruit trees. 2. On the average, optimum potash rates on barley, wheat, soybean, corn, white potato and sweet potato were 6.5, 6.9, 4.5, 8.1, 8.9, and 17.7kg per 10a respectively. Yield increaments per 1kg of potash per 10a were 4-5kgs on the average for cereal crops, 68kg for white potato, and 24kg for sweet potato. 3. According to the soil testing data, the exchangeable potassium in the coastal area was higher than that in the inland area and medium in the mountainous area. The exchangeable potassium per province in decreasing order is Jeju>Jeonnam>Kangweon>Kyongnam. Barley : 4. The response of barley to an adequate rate of potassium seemed to be affected more by differences in climatic conditions than to the nature of the soil. 5. The response and the adequate rate of potassium in the southern area, where the temperature is higher, were low because of more release of potassium from the soil. However, the adequate rate of phosphorus was increased due to the fixation of applied phosphorus into the soil in high temperature regions. The more nitrogen application would be required in the southern area due to its high precipitation. 6. The average response of barley to potassium was lower in the southern provinces than northern provinces. Kyongsangpukdo, a southern province, showed a relatively higher response because of the low exchangeable potassium content in the soil and the low-temperature environment in most of cultivation area. 7. Large annual variations in the response to and adequate rates of potassium on barley were noticed. In a cold year, the response of barley to potassium was 2 to 3 times higher than in a normal year. And in the year affected by moisture and drought damage, the responses to potassium was low but adequate rates was higher than cold year. 8. The content of exchangeable potassium in the soil parent materials, in increasing order was Crystalline Schist, Granite, Sedimentary and Basalt. The response of barley to potash occurred in the opposite order with the smallest response being in Crystalline Schist soil. There was a negative correlation between the response and exchangeable potassium contents but there was nearly no difference in the adequate rates of potassium. 9. Exchangeable potassium according to the mode of soil deposition was Alluvium>Residium>Old alluvium>Valley alluvium. The highest response to potash was obtained in Valley alluvium while the other s showed only small differences in responses. 10. Response and adequate rates of potassium seemed to be affected greatly by differences in soil texture. The response to potassium was higher in Sandy loam and Loam soils but the optimum rate of potassium was higher in Clay and Clay loam. Especially when excess amount of potassium was applied in Sandy loam and Loam soils the yield was decreased. 11. The application of potassium retarded the heading date by 1.7 days and increased the length of culm. the number of spikelet per plant, the 1,000 grain weight and the ratio of grain weight to straw. Soybean : 12. Average response of soybean to potassium was the lowest among other cereal crops but 28kg of grain yield was incrased by applying potash at 8kg/10a in newly reclaimed soils. 13. The response in the parent materials soil was in the order of Basalt (Jeju)>Sedimentay>Granite>Lime stone but this response has very wide variations year to year. Corn : 14. The response of corn to potassium decreased in soils where the exchangeable potassium content was high. However, the optimum rate of applied potassium was increased as the soil potassium content was increased because corn production is proportional to the content of soil potassium. 15. An interaction between the response to potassium and the level of phosphorus was noted. A higher response to potassium and higher rates of applied potassium was observed in soils contained optimum level of phosphorus. Potatoes : 16. White potato had a higher requirement for nitrogen than for potassium, which may imply that potato seems to have a higher capability of soil potassium uptake. 17. The yield of white potato was higher in Sandy loam than in Clay loam soil. Potato yields were also higher in soils where the exchangeable potassium content was high even in the same soil texture. However, the response to applied potassium was higher in Clay loam soils than in Sandy loam soils and in paddy soil than in upland soil. 18. The requirement for nitrogen and phosphorus by sweet potato was relatively low. The sweet potato yield is relatively high even under unfavorable soil conditions. A characteristics of sweet potatoes is to require higher level of potassium and to show significant responses to potassium. 19. The response of sweet potato to potassium varied according to soil texture. Higher yields were obtained in Sandy soil, which has a low exchangeable potassium content, by applying sufficient potassium. 20. When the optimum rate of potassium was applied, the yields of sweet potato in newly reclaimed soil were comparable to that in older upland soils.

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