• Journal of Food Hygiene and Safety
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• v.37 no.4
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• pp.238-248
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• 2022

This study was conducted to evaluate the safety of 208 types of residue pesticides on 150 dried agricultural products in Ulsan. The pesticide residues were detected using GC-MS/MS, LC-MS/MS, GC/ECD, GC/NPD, and LC/PDA. The detection rate was 19.3% (29 of 150 samples), and 28 types of pesticides were detected. Two of the 29 pesticide residues exceeded the maximum residue limit (MRL). Difenoconazole was detected in Ulleungdo aster, and chlorothalonil and chlorpyrifos were detected in chili pepper leaves. In the vegetable group, the frequency of pesticide residues was found to be the highest in dried leafy vegetables, followed by dried fruiting vegetables other than cucurbit vegetables, and then dried stalk and stem vegetables. The pesticide types detected in the commercial dried agricultural products were fungicide (60%), insecticide (23.8%), and acaricide (16.3%). In the validation study, the values of limit of detection (LOD), limit of quantitation (LOQ), coefficient of determination (R²), and recovery rate were in the range of 0.0001-0.0409 mg/kg, 0.0003-0.1241 mg/kg, 0.994-0.999, and 81.58-116.79%, respectively. The ratio of estimated daily intake (EDI)/acceptable daily intake (ADI) was 0.00002-0.31395%.

• Journal of Practical Agriculture & Fisheries Research
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• v.15 no.1
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• pp.85-93
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• 2013

This study has been conducted to investigate the effect of GA₃ solution dipping treatment after 1 days full bloom on spike growth and fruit quality at harvest of 'Campbell Early' grapevine. The fruit cluster growth(weight, length, width) and fruit stalk(diameter, length) at harvest were increased significantly by GA₃ 10 mg·L^-1 solution dipping treatment compared to control and another concentration. The berry growth (berry No, weight, length, diameter) at harvest showed no difference by treatment GA₃ concentration different. Spike weight was increased by GA₃ 5, 10, 20, mg·L^-1 treatment compared to control, but no difference GA₃ 40 mg·L^-1 treatment. The degree of compact berry, bloom, skin color and SSC at harvest by GA₃ solution dipping treatment were not significantly different from those of control. but increased seedlessness induction by GA₃ 10 mg·L^-1 treatment. The occurrence percent of berry cracking by GA₃ 5, 10, 20, 40 mg·L^-1 treatment significantly decreased. The bitter rot of berry harvest showed no difference by treatment GA₃ concentration different. Total spike length was increased by GA₃ 5, 10 mg·L^-1 treatment compared to control and GA₃ 20, 40 mg·L^-1 treatment. The spike length of 1st from 15th to position increased by GA₃ 10 mg·L^-1 treatment.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.84-84
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• 2022

The limit of crop cultivation is moving northward due to the temperature rise by climate change. There is a problem with crop growth if early sowing is performed at a time when the temperature is low. It is difficult to secure crop productivity and cultivation stability due to the low temperature and short cultivation period. Therefore, this study was conducted to analyze the change in growth characteristics and yield of corn for grain when early sowing is performed in central region of South Korea. This experiment was conducted at experimental field of Suwon in 2021. Three varieties of corn for grain such as Kwangpyeongok, Sinhwangok, and Hwangdaok were sown at intervals of 5 days from 20 March to 15 April. The planting density at this time was sown with a row interval of 70 cm and a plant interval of 25 cm. Nitrogen, phosphoric acid, and potassium fertilizers were applied at 17.4 kg, 3.0 kg, and 6.9 kg per 10a, respectively. Phosphoric acid and potassium fertilizers were all applied before sowing and nitrogen fertilizer was applied 50% before sowing and 50% in the fifth leaf period. The corn growth characteristics and yield components were investigated. The seedling establishment rate by sowing date was in the range of 68.5~88.5%, and it showed a difference depending on the variety. The range of days from sowing to tassel and silk emergence by sowing date was 79.9~98.4 and 81.0~98.9 days, respectively. As the sowing date was delayed, the days from sowing to tassel and silk emergence decreased. The growth characteristics and yield of corn by sowing date are as follows. Plant height was the highest at 241.3 cm at the sowing on 25 March, and Stalk diameter was the thickest at 25.6 mm at the sowing on 31 March. The fresh weight per plant was the highest at 728 g at the sowing on 25 March, and the dry weight per plant was the highest at 185 g at the sowing on 31 March. Corn growth characteristics did not show a certain trend depending on the sowing date, and corn growth was more vigorous at the sowing on March 25 and 31 than the others. In the case of ear weight, it was the heaviest with 344 g at the sowing on 25 March, and filled ear length ratio showed a tendency to decrease as the sowing time was delayed. The weight of 100 grains and grain yield per 10a of maize were the highest at 36.0g and 878.7kg/10a, respectively at the sowing on 25 March. Although the growth and yield of corn for grain were good during early sowing in the central region of South Korea, it is necessary to investigate the limit temperature for early sowing of corn by examining the annual variation according to weather conditions.

• Journal of Korean Society of Forest Science
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• v.62 no.1
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• pp.24-42
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• 1983

To develop Ilex cornuta which grow naturally in the southwest seaside district as new ornamental tree, the author chose I. cornuta growing in the four natural communities and those cultivated in Kwangju city as a sample, and investigated its ecology, morphology and characteristics. The results obtained was summarized as follows; 1) The natural distribution of I. cornuta marks $35^{\circ}$43'N and $126^{\circ}$44'E in the southwestern part of Korea and $33^{\circ}$20'N and $126^{\circ}$15'E in Jejoo island. This area has the following necessary conditions for Ilex cornuta: the annual average temperature is above $12^{\circ}C$, the coldness index below $-12.7^{\circ}C$, annual average relative humidity 75-80%, and the number of snow-covering days is 20-25 days, situated within 20km of from coastline and within, 100m above sea level and mainly at the foot of the mountain facing the southeast. 2) The vegetation in I. cornuta community can be divided that upper layer is composed of Pinus thunbergii and P. densiflora, middle layer of Eurya japonica var. montana, Ilex cornuta and Vaccinium bracteatum, and the ground vegetation is composed of Carex lanceolata and Arundinella hirta var. ciliare. The community has high species diversity which indicates it is at the stage of development. Although I. cornuta is a species of the southern type of temperate zone where coniferous tree or broad leaved, evergreen trees grow together, it occasionally grows in the subtropical zone. 3) Parent rock is gneiss or rhyolite etc., and soil is acidic (about pH 4.5-5.0) and the content of available phosphorus is low. 4) At maturity, the height growth averaged $10.48{\pm}0.23cm$ a year and the diameter growth 0.43 cm a year, and the annual ring was not clear. Mean leaf-number was 11.34. There are a significant positive correlation between twig-elongation and leaf-number. 5) One-year-old seedling grows up to 10.66 cm (max. 18.2 cm, min. 4.0 cm) in shoot-height, with its leaf number 12.1 (max. 18, min), its basal diameter 2.24 mm (max. 4.0 mm, min. 1.0 mm) and shows rhythmical growth in high temperature period. There were significant positive correlations between stalk-height and leaf-number, between stalk-height and basal-diameter, and between number and basal diameter. 6) The flowering time ranged from the end of April to the beginning of May, and the flower has tetra-merouscorella and corymb of yellowish green. It has a bisexual flower and dioecism with a sexual ratio 1:1. 7) The fruit, after fertilization, grows 0.87 cm long (0.61-1.31 cm) and 0.8 cm wide (0.62-1.05 cm) by the beginning of May. Fruits begin to turn red and continue to ripen until the end of October or the beginning of November and remain unfading until the end of following May. With the partial change in color of dark-brown at the beginning of the June fruits begin to fall, bur some remain even after three years. 8) The seed acquision ratio is 24.7% by weight, and the number of grains per fruit averages 3.9 and the seed weight per liter is 114.2 gram, while the average weight of 1,000 seeds is 24.56 grams. 9) Seeds after complete removal of sarcocarp, were buried under ground in a fixed temperature and humidity and they began to develop root in October, a year later and germinated in the next April. Under sunlight or drought, however, the dormant state may be continued.

• Clinical and Experimental Pediatrics
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• v.50 no.11
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• pp.1110-1115
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• 2007

Purpose : Idiopathic central diabetes insipidus (CDI) is defined in CDI patients without definite etiology. Some patients initially diagnosed as idiopathic CDI progressed to organic causes. We reviewed clinical, endocrinological, and radiological courses of 20 patients who was initially diagnosed as idiopathic CDI, to assess the predicting factors for progression to brain tumors. Methods : We reviewed the medical data and followed up their clinical courses in 20 CDI patients who had no definite organic etiology, such as malformation, tumor, at the time of diagnosis. Results : Our study included 15 males and 5 females. Mean age of CDI diagnosis was $7.8{\pm}3.6$ (2.1-14.7) years. Mean follow-up duration was $8.6{\pm}5.1$ (1.5-18) years. Six (30%) patients were diagnosed as brain tumor during follow-up. Ten (50%) of 20 patients had growth hormone deficiency. Multiple pituitary hormone deficiencies were found more frequently in brain tumor patients than idiopathic patients (60% vs 7%, P=0.037). Pituitary stalk thickening (PST) and loss of posterior pituitary signal were observed in 9 patients (47%), respectively. The newly development of PST was observed in patients diagnosed as brain tumor. Conclusion : About 30% of idiopathic CDI patients progress to organic disease such as germ cell tumor or histiocytosis. If there are multiple anterior pituitary hormone deficiency or newly development of PST, more close and careful follow-up is needed.

• Journal of Life Science
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• v.19 no.5
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• pp.581-586
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• 2009

Bell pepper plants (Capsicum annuum cv. Plenty) were grown under low night temperatures (LNT: day/night temperature of $28/13^{\circ}C$) and optimum night temperatures (ONT: day/night temperature of $28/20^{\circ}C$) in growth chambers. Pollen grains were collected from plants in the growth chamber and incubated at 10, 15, 20, 25, and $30^{\circ}C$. After 24 hr incubation, in both ONT and LNT, the highest percent pollen germinations were observed at $25^{\circ}C$ followed by germinations at $30^{\circ}C$. Percent pollen germination at $25^{\circ}C$ was 42% in ONT - two times higher than in LNT at 21%. Pollen tube length was much longer at ONT than at LNT, regardless of incubation temperature. Compared with other treatments, earlier and quicker pollen tube elongation was observed in ONT pollen grains incubated at $25^{\circ}C$. To find pollen viability in plant growing conditions, pollen grains were incubated in LNT ($28/13^{\circ}C$) and ONT ($28/20^{\circ}C$) growth chambers for 24 hr. Petri-dishes with pollen grains were put in the growth chambers at the beginning of the night condition. Pollen grains in the LNT growth chamber did not germinate at night ($13^{\circ}C$), but began to germinate when the day condition ($28^{\circ}C$) started. Pollen grains in the ONT condition, however, started germinating from the early night ($20^{\circ}C$) and germination continued during the day ($28^{\circ}C$). Plants in LNT showed increased flower stalk length, ovary diameter, stamen length, flower weight, and fruit length. LNT conditions did not impair seed set. There were no differences in seed sets between fruits at LNT and ONT. Normal seed sets in LNT show that fertilization may be completed during daytime. However, further investigation is needed to find what extent of temperature stress causes malformed and/or parthenocarpic fruits in this bell pepper.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.1
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• pp.45-52
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• 1985

Phytotron and field experiments were conducted to determine the influence of morphological development and environmental temperature on synthesis, translocation and accumulation behaviour of Fructosan, Monoand Disaccharose in corn cv. Blizzard and fodder sorghum cv. Sioux and Pioneer 931 at Munich technical university. Sorghum and maize plants were grown for 42 days at 4 temperature regimes (30/25, 25/20, 28/18 and 28/8 dog C) and mid-summer sunlight over 13-h days. The obtained results are summarized as follows: 1 Non-structural carbohydrates in maize and sorghum were accumulated mainly as Mono- and Disaccharose. The concentrations of Mono- and Disaccharose were increased markedly after differentiation of growing points and shown at early milk stage the highest contents with 27.8-29.1% and 16.8-20.4% for maizeand sorghums respectively. 2. Non-structural carbohydrates were accumulated mainly in stalk. However, during the late maturity the most of Mono- and Disaccharose were translocated into grain and reserved as starch. The increase of starch was associated with decrease of total non-structural carbohydrates. 3. Fructosan synthesis was not affected by morphological changes and environmental factors, which shows a value of 1.5-2.5% in whole stage of maize and sorghum. 4. Sorghum and maize plants were shown to have a great photosynthetic rates to high temperature. Reserved Mono- and Diaaccharose were, however, declined when temperature exceeded 30 dog C. Under cold stress at l8/8 deg C non-structural carbohydrates were not translocated and also were accumulated in leaves too much that cause to restrict of photosynthesis. 5. Net Energy Lactation (NEL) of sorghum and maize were directly associated with synthetic rates of non-structural carbohydrates, especially Mono- and Disaccharose. The highest values of NEL were found at physiological maturity stage with 6.6- 6.9 MJ and 5.7-6.0 MJ-NEL/kg for maize and sorghum respectively.

• Korean Journal of Environmental Agriculture
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• v.19 no.3
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• pp.201-205
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• 2000

Eleven runoff $plots(3{\times}15\;m)$ were built on a sloping field of a high plateau in Kangwon Province, Korea. The plots were treated with different tillage, residue covers and fertilizers, corn and potato were cultivated, and sediment discharge was measured from the plots for 3 years. Agricultural management practices were monitored around the plots to develop adequate best management practices. The least sediment occurred from the plots with no-till and 100% residue cover $(corn,\;0.1{\sim}2.2\;t/ha/year)$ and with contour tillage and vinyl sheet cover plots $(potato,\;0.1{\sim}0.2\;t/ha/year)$. The largest sediment was measured from the plots with up-and-down till and no cover ($11{\sim}33$ and $16{\sim}31\;t/ha/year$ from corn and potato plots, respectively). The type of organic and commercial fertilizers seemed not to affect sediment discharge. Sediment discharge from contour plots were largely dependent on the collapse of ridges due to the flush of water stored in furrows. The sediment discharge from contour corn and potato plots with no residue cover was $10{\sim}27$ and $16{\sim}24\;t/ha/year$, respectively. No-till with residue cover, vinyl cover for tuber crops, construction of furrow dam, frost heave research, furrow and ridge tillage with furrow dam after tuber crop harvest, limited stalk harvest of row crops, use of winter cover crops, and other common best management practices were recommended to minimize the sediment discharge from a high plateau sloping land culture.

• Korean Journal of Environmental Agriculture
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• v.32 no.3
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• pp.201-206
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• 2013

BACKGROUND: Kiwifruit, which was introduced to Korea in late 1970s, is a warm-temperate fruit tree, whose leaves are easily damaged by wind because of their large size. To produce high quality fruits, efficient windbreak is necessary to protect leaves until harvest. In Korea, typhoons from July onwards usually influence the production of kiwifruit. Damages from typhoons include low fruit quality in the current year and low flowering ratio the following year. This study was conducted to investigate the effect of early defoliation of kiwifruit vines from July to October on the regrowth of shoot axillary buds the current year and bud break and flowering the following year. METHODS AND RESULTS: Scions of kiwifruit cultivar 'Goldrush' were veneer grafted onto five-year-old Actinidia deliciosa rootstocks, planted in Wagner pots (13L) and grown in a rain shelter. Kiwifruit leaves in the proximity of leaf stalk were cut by lopping shears to simulate mechanical damage from typhoon since only leaf stalks were left when kiwifruit vines were damaged by typhoons. Kiwifruit vines were defoliated from July 15 to October 14 with one monthintervals and degrees of defoliation were 0, 25, 50, 75 and 100%. All experiments were conducted in the rain shelter and replicated at least five times. Defoliation in July 15 resulted in a high regrowth ratio of 20-40% regardless of degree of defoliation but that in August 16 showed only 5.8% of regrowth ratio in the no defoliation treatment; however, more than 25% of defoliation in August 16 showed 17-23% of regrowth ratio. In September 15, regrowth ratio decreased further to less than 10% in all treatments and no regrowth was observed in October 14. Percent bud break of all defoliation treatments were not significant in comparison to 64.7% in no defoliation except for 42.1% and 42.9% in 100% defoliation in July 15 and August 16, respectively. Floral shoot in the no defoliation treatment was 70.2% and defoliation of 50% or less resulted in the same or increased floral shoot ratio in July 15, August 16, and September 15; however, defoliation in October 14 showed no difference in all treatments. In flower number per floral shoot, 2-3 flowers appeared in no defoliation and only 1 flower was observed when the vines were defoliated more than 50% in July 15 and September 15. In October 14, contrary to the floral shoot ratio, flower number decreased with increased defoliation. CONCLUSION(S): Therefore, it is suggested that dormancy of 'Goldrush' axillary buds, was started in August and completed in October. The effect of defoliation on bud break of axillary buds the following year was insignificant, except for 100% defoliation in July 15 and August 16. From July 15 to September 15, floral bud ratio was significantly reduced when more than 50% of leaves were defoliated compared to no defoliation. Also, the number of flowers per flower-bearing shoot the following year decreased by less than 50% when compared to no defoliation, and this decrease was more prominent in September 15 than July 15 and August 16.

• Journal of Bio-Environment Control
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• v.7 no.3
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• pp.226-236
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• 1998

If the lowest leaves of the cucumber were removed or training cultivable method was changed, a computer vision system could divide well the cucumber fruit from the others, and also an end-effector could reach and grip cucumber fruit and cut well its fruit stalk. Therefore, this study investigated whether removal leaves and training cultivable method of a cucumber could affect its growth and yield. They can help to be designed the vision system and the end-effector. A cucumber fruit grew by 6-l5cm long for 2 days regardless of removing leaves. Removal leaves didn't affect growth of cucumber fruit. Number of cucumber fruit was produced within 10% different values by three methods (A, B, C) of removal leaves. The first grade rate (best quality) of 4 B and C was 56.7%, 53.1%, 56.3% respectively. Consequently, proper removal leaves were better than traditional way, which does not remove a leaf, because they make cucumber plant ventilate more freely and absorb more light.