• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.4
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• pp.304-310
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• 1981

In order to observe the degree and response of drought-resistance and its physiological mechanism in barley and wheat, 5 species (16 cultivars) were tested for changes in plant height, seedling dry weight, chlorophyll content, leaf relative turgidity, soluble protein, reducing sugar and growth of seedling subjected to water stress by withholding watering for 8 days at 10 days (at the 3rd leaf stage) after emergence. The average rate of decrease of all cultivars was 15% in plant height, 24% in seedling dry weight, 32% in chlorophyll content, 27% in leaf relative turgidity, and 27% in protein. But reducing sugar content of control was increased 4 folds more than that of water stress. In the decreased rate of seedling dry weight of each cultivar, rye was shown to be lowest rate, and Baegdong, Mokpo #55, and 3 two-row barley were shown to be the highest rate. The degree of the decreased rate in 5 species was in the order of rye < < wheat < covered barley < naked barley < two-row barley. in the decreased rate of chlorophyll content, rye, Cheonggaemil and Olmil are the lowest group, and the highest one are Milyang #12, Bangsa #6, Hyangmaeg and Sacheon #4. In the decreased rate of leaf relative turgidity, the lowest group (22-25%) were rye, Cheonggaemil and Dongbori #1, and, on the other hand, the highest group (30-33%) were Baegdong and 3 two-row barley. In the decreased rate of soulble protein, the lowest group (14-17%) were Chogwang, Geurumil, Dongbori #1, and Mokpo #55, and the highest one was 3 two-row barley. The increased ratio of reducing sugar of water stress to control was 4 to 5 folds in rye and wheat, and about 2 folds in naked barley and 3 two-row barley. The degree of the increased ratio of 5 species was in the order of rye > wheat > covered barley > naked barley > two-row barley. In terms of the physiological and adaptive metabolism during the processing leading to drought-resistance, the degree of drought-resistance of 5 species to water stress at seedling stage was shown to be in the order of rye > wheat > covered barley > naked barley > two-row-barley.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.666-672
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• 1997

Twenty years' daily mean air temperature data was used to calculate the critical early seeding date(CESD), the optimum heading date(OHD), the critical late heading date for stable ripening(CHDR) and the critical late ripening date(CLRD) for rice seeded on dry paddy in different agroclimatic zones in Korea. The CESD was defined as the first day with mean air temperature of 13$^{\circ}C$, and the OHD as the first day of the 40 consecutive days with mean air temperature of 22$^{\circ}C$ or above after heading. The CHDR was defined as the date after which the cumulative daily mean air temperature would be at least 76$0^{\circ}C$. Lastly, the CLRD was defined as the last day when daily mean air temperature remains above 15$^{\circ}C$. This information was used for the estimation of periods from the earliest date of seeding to optimum heading date, the latest possible date of heading and the latest possible date of ripening in respective regions. For instance, in Suwon, those respective periods mentioned were found to be 104days, 124days, and 165days.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.2
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• pp.124-130
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• 2016

In this study, agronomic characteristics and fatty acid composition of 121 flax (Linum usitatissimum L.) germplasms were analyzed. The flax germplasms had a fairly short growth period of 75-95 days. The plant height at maturity varied from 52 to 124 cm. The flower color varied from white to lilac and even purple. Early flowering flax germplasms had white flowers and were resistant to lodging. In early flowering flax germplasms, all agronomic characteristics, including growth period, plant height, branch number per plant, stem diameter, number of capsules per raceme, seed number per capsule, 1000-seed weight, and seed yield, were decreased. The average fatty acid composition of 121 flax germplasms comprised palmitic acid (5.3%), stearic acid (4.3%), oleic acid (29.7%), linoleic acid (13.1%) and linolenic acid (46.4%). The total content of unsaturated fatty acids ranged from 84~94% with an average of 88%. Among the fatty acids, linolenic acid (omega-3) content was the highest with a range of 36~54%. In five selected flax germplasms (Hollandia 1803, Red son, C & F Res Br 1767, Wiera, and Ireland 1657) with high linolenic acid (${\geq}51%$), total lipid and protein contents were 30~36% and 5.4~6.9%, respectively. Overall, flax can practically be adoptable into cropping systems in South Korea and utilized as a scenery crop, since flax has a short cultivation period with diverse flower colors.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.4
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• pp.376-381
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• 2008

Anthocyanin contents of black soybean were analyzed for development of superior breeding lines with high anthocyanin contents. Total 292 genotypes of black soybean collected through the whole country were analyzed by HPLC in which C3G (Cyanidin-3-Glucoside), D3G (Delphinidin-3-glucoside), and Pt3G (Petunidin-3-Glucoside) were detected main anthocyanin pigments and each pigment contents were significantly different according to genotypes. C3G content showed the highest value in all materials and its variation was also wide, whereas D3G and Pt3G were not detected in 4 and 24 genotypes. Mean value of C3G, D3G, and Pt3G contents were $8.05{\pm}4.225$, $1.80{\pm}0.854$, and $1.15{\pm}0.781\;mg/g$, respectively. In case collected sites, genotypes collected in Chungnam region were higher the anthocyanin contents than other collections, which was $13.75{\pm}3.861\;mg/g$. It might be concluded that it takes more than 36 days for anthocyanin accumulation since beginning of seed-coat pigments formation, in that case it showed $13.09{\pm}4.190\;mg/g.$. Also total anthocyanin contents were present higher concentration in seed coat as maturation period was longer from flowering stage.

• Development and Reproduction
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• v.8 no.2
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• pp.91-97
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• 2004

The objective of this study was to assess that the effects of DEHP administration on reproductive characteristics and blood hematological and chemical values in pups born after DEHP administration in pregnant mice. DEHP was administrated to pregnant mice by intraperitoneally injection with 0, 0.5, 1.0 and 10.0mg/kg B.W, 5 times at 3 days interval from Day 1 to Day 16 in the gestation period. The body weight and reproductive organ weight(testis, epididymis and coagulating gland) in male pups on 45 day after birth was not affected in all experimental groups, but vesicular gland in DEHP groups was significantly lower than that of control group(P<0.05). The semen characteristics of male pups were not affected in DEHP treatment groups. The WBC, HB, HT, MCH and albumin values in male pups were not affected in all experimental groups, but RBC MCV, MCHC, PLT and total protein values were significantly different among the experimental groups(P<0.05). In female pups, the effects of DEHP administration were not affected the body and uterus weight, but the left ovary in 10.0mg DEHP group was significantly heavier than in control and 0.5mg DEHP group(P<0.05). The WBC, MCV, MCH, MCHC, PLT, albumin, BUN and total protein values in female were not different in all experimental groups. The RBC, HB and HT values were significantly different among the experimental gruop(P<0.05). The historical evaluation of testis in male pups that were grown to 45 days after birth was not different in all experimental groups. The ovary in female pups had many corpus luteum in 10.0mg DEHP group. The endometriosisi of uterus was significantly decreased in DEHP group. There results suggest that low concentration of DEHP administration in pup born after DEHP administration in pregnant mice was not affered on reproductive characteristic, but was affected on blood hematological and chemical values.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.4
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• pp.414-421
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• 2019

Pod shattering during the maturing stage causes a serious yield loss in soybean. It is the main limiting factor of soybean cultivation and mechanization. It is important to develop varieties suitable for mechanical harvesting and to develop energy-efficient agricultural machinery to save labor and costs. 'Daewonkong,' developed by the National Institute of Crop Science (NICS) in 1997, is an elite cultivar that occupies more than 80% of the soybean cultivation area in Korea because of its strong tolerance to pod shattering. The objectives of this study were to investigate the variation in pod shattering degree in a RIL population developed from a 'Daewonkong' parent and to select promising lines with pod shattering tolerance. 'Daewonkong' demonstrated a high level of tolerance to pod shattering compared to the 'Tawonkong' and 'Saeolkong' varieties, with no shattered pods after 72 hours of drying. Screening of pod shattering showed a clear distinction between the tolerant and susceptible varieties. Also, the distribution of shattering pod ratio in the two populations showed a similar pattern for three years. The promising lines with pod shattering tolerance included 27 lines in the 'Daewonkong'×'Tawonkong' population and 21 lines in the 'Daewonkong'×'Saeolkong' population. The promising lines are expected to be widely used as breeding parents for creating soybean cultivars with pod shattering tolerance.

• Journal of Korean society of Dental Hygiene
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• v.4 no.1
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• pp.105-117
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• 2004

The purpose of this study was to examine the effect of aroma therapy on anxiety and pain before and after tooth extraction. The subjects in this study were 60 patients who felt severe anxiety and pain due to tooth extraction. The experiment was conducted from January through March, 2004, by organizing an experimental group and a control group with 30 patients each. The experimental group was asked to keep wearing lavender-containing necklaces from two days before tooth extraction to inhale lavender, and no such an action was taken to the control group. The collected data were analyzed with SPSS 10.0 program to obtain statistical data. and ${\times}2$ test and t-test were implemented. The findings of this study were as follows: 1. Regarding whether or not the experimental and control groups were homogeneous, men outnumbered women, and the largest number of the patients were in their 30s. Those who were married were more than the others who were unmarried in number, and those who lived with their spouses under the same roof together outnumbered the others who didn't, as the rate of the former stood at 65 percent in the experimental group and 86.4 percent in the control group. They expressed high satisfaction at their spouses, since 45 percent of the experimental group and 31 percent of the control group did it, but the difference between them and those who were unsatisfied was insignificant (pE0.347). By occupation, the largest number of people in the experimental group, which numbered 16.7 percent, were self-employed, and lots of patients in the control group were government workers. As for blood type, type A was most prevailing, which recorded 43.3 percent. By religion, 43 percent of the experimental group had no religion, whereas 36.7 percent of the control group were Christian. The most common monthly income ranged from 2 million to 2.5 million won. 2. There was little disparity in past pain experience between the two groups before aroma therapy was applied. The experimental group underwent more pain (6.15) than the control group (5.78), but the difference wasn't significant. The experimental group (90%) experienced more anxiety and fear than the control group(83%), but the difference was insignificant. This fact showed that there was little gap between the two groups in anxiety and fear caused by tooth extraction. Contrary to earlier expectation that pre-anxiety might not be the same. little significant difference was found. 3. After aroma therapy was applied, 50 percent of the experimental group and 23.3 percent of the control group suffered significantly less anxiety and fear about tooth extraction(${\times}2$=4.59, pE.05). And the experimental group exposed to aroma therapy was less nervous(3.0) than the control group(4.39), and the gap between the two was significant (t=13.37, pE.001). Therefore, aroma therapy had a good effect on alleviating their anxiety. During tooth extraction. 73.3 percent of the experimental group and 93.3 percent of the control group felt pain. The former group suffered Significantly less pain(${\times}2$=4.32, PE.05). Concerning the extent of pain, the experimental group(2.53) found it less painful to have their teeth extracted than the control group(5.50), and the gap between the two was significant(t=5.89, PE.05). 4. As to the effect of aroma therapy on alleviating anxiety or fear, the experimental group(33.3%) felt that aroma therapy let them more relieved. Every member of that group was willing to use aroma therapy again in the future, and 86.7 percent of that group perceived that aroma therapy made a difference to dental treatment. The experimental group responded to aroma therapy favorably, as every member of it had an intention to advise others to use that therapy.

• Korean Journal of Environmental Agriculture
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• v.21 no.1
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• pp.7-16
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• 2002

Contamination of groundwater by agrochemicals used in the regional-scale Is now a major environmental problem, and this is especially true for Cheju island where virtually all potable water is from groundwater. The objective of this study was to assess leaching potential of eight pesticides in soils of citrus orchards using groundwater ubiquity score (GUS), retardation factor (RF) and attenuation factor (AF). Considering GUS estimated in 30 citrus orchard soils, metribuzin and metolachlor were classified as leacher, alachlor in volcanic ash soils and linuron in non-volcanic soils were classified as leacher, but chlorothalonil and chlorpyrifos were classified as non-leacher. For RF values, metribuzin was classified to be mobile in soils of low organic carbon, metolachlor and alachlor were classified to be moderately immobile in most soils, but linuron, diuron, diniconazole, chlorothalonil and chlorpyrifos were all classified to be very immobile. For AF values, diniconazole, chlorothalonil, and chlorpyrifos were classified to be very unlikely leachable in all of the soils, metribuzin was classified to be likely leachable, and metolahclor, alachlor, linuron and diuron were classified to be leachable only in non-volcanic soils. Although there were some variations in the relative potential of teachability of pesticides estimated with the three different indices, the ranking was essentially determined on the base of the intrinsic properties of the chemicals and environmental properties. Among the eight pesticides, metribuzin, metolachlor, and alachlor, which have high water solubility and low $K_{oc}$ values, have a significant leaching potential especially in non-volcanic ash soils of low organic carbon. But diniconazole, chlorothalonil, and chlorpyrifos, which have low water solubility and high $K_{oc}$ values, were classified to be very immobile in all of the soils. Therefore, to lower the possibility of pesticide contamination of the groundwater in Cheju island, those pesticides which have high water solubility and low $K_{oc}$ values should be used with care in soils of low organic carbon including non-volcanic ash soils.

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.394-398
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• 1997

Changes of nutrient material and heavy metals of irrigation water and natural supplies by irrigation water into 1.0ha of paddy field during the rice cultivation was investigated pH of irrigation water ranged 6.458.34 and electrical conductivity showed $110{\mu}S/cm$ in the first irrigation period and commonly showed $90{\mu}S/cm$. The content of T-N, NH4-N and $NO_3-N$were 3.09~12.36, 0.17~1.34 and 2.70~10.72mg/L respectively. The content of T-P was 0.09~0.22mg/L and ortho-P was not detected. The content of $Ca^{++},\;Mg^{++},\;Na^+\;and\;K^+$ showed 0.89~5.12, 1.12~2.76, 1.74~4.52 and 1.34~4.18mg/L regardless of irrigation season respectively. Only Cu and Zn of heavy metals were detected 0.001~0.009 and 0.007~0.091mg/L, but Pb, Cd, Cr and Ni were not detected When supplied $4,250m^3$ of an irrigation water into 1.0㏊ of paddy field, natural supplies of nutrient materials were 29.67㎏ of T-N, 1.80㎏ of $NH_4-N$, 24.57kg of NO3-N and 0.51kg of T-P. Also $Ca^{++},\;Mg^{++},\;Na^+,\;K^+,\;Cl^-\;and\;SO_4\;^{2-}$ were supplied 9.42, 7.09, 13.34, 9.08, 40.27 and 41.38kg respectively. Only Cu and Zn of heavy metals were supplied 0.017kg of Cu and 0.133kg of Zn, Pb, Cd, Cr and Ni were not supplied

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.399-403
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• 1997

Changes of nutrient material and natural supplies by sediment of irrigation water into 1.0ha of paddy field during the rice cultivation were investigated. TSS of the sediment contained irrigation water ranged 52.9${\sim}$125.6mg/L and content of organic matter showed 1.89${\sim}$2.33%. Content of T-N, $NH_4-N$ and $NO_3-N$ were 623.5${\sim}$1775.2, 22.9${\sim}$75.8 and 10.2${\sim}$72.1mg/kg respectively. Content of T-P and ortho-P were 186.7${\sim}$375.7 and 12.4${\sim}$38.9mg/kg respectively. The content of exchangeable canons, $Ca^{++},\;Mg^{++}\;Na^+\;and\;K^+$ were 435.3${\sim}$737.5, 127.3${\sim}$204.2, 36.6${\sim}$94.9 and 105.6${\sim}$232.9mg/kg respectively. Total content of heavy metals were 13.4 of Pb, 0.6 of Cd, 8.2 of Ni, 12.1 of Cu, 29.8 of Zn and 19.7mg/kg of Cr. During the period of rice cultivation, when supplied 4,250m^3 of an irrigation water into 1.0ha of paddy field, natural supplied 346.01kg of sediment, 7.11kg of organic matter, 0.50kg of T-N, 0.02㎏ of NH_4-N, 0.01kg of NO_3-N, 0.08kg of T-P and 0.01㎏ of Ortho-P. Also exchangeable $Ca^{++},\;Mg^{++}\;Na^+\;and\;K^+$ were supplied 0.21, 0.06, 0.02 and 0.06kg respectively. Loaded of the total heavy metal showed natural background level.