• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.10 no.2
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• pp.164-169
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• 1999

Background and Objectives : The intracordal cysts are more increasingly diagnosed and treated due to advanced laryngeal stroboscopy and laryngeal microsurgical technique. The intracordal cysts are frequently misdiagnosed as vocal polyp or nodule The purpose of this study is to evaluate clinical features of intracordal cysts. Materials and Methods : In the present series, 83 cases of the intracordal cysts treated with laryngeal microsurgery are reported. The intracordal cysts are diagnosed preoperatively with indirect laryngoscopy, laryngeal endoscopy, laryngeal stroboscopy and confirmed with laryngeal microsurgical findings and biopsies. Results : Intracordal cysts are 83 of 1900 patients treated with laryngeal microsurgery(4.4%)-ductal cysts are 56 cases and epidermoid cysts are 27 cases. Intracordal cysts are more frequent in women, forties and the frequent site is an anterior third of the true vocal cord. With the indirect laryngoscopic examination, the ductal cysts are frequently misdiagnosed as vocal polyps or nodules but the epidermoid cysts are relatively easily diagnosed. The etiologic factors of the intracordal cysts are suspected as voice abuse and upper respiratory infection. The degree of postoperative voice satisfaction is similar to that of the vocal polyps. Conclusion : Intracordal cysts are frequently misdiagnosed as polyps or nodules, therefore preoperative stroboscopic findings and laryngeal microsurgical findings is important. An ideal treatment is to enucleate the cysts avoiding rupture of cyst and injury of lamina propria of the vocal cord.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.375-384
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• 2010

We tried to establish the history of outbreaks and control methods of 'hwangchung' in Joseon Dynasty, uncovering the biological reality of the 'hwangchung' (called hwang or bihwang) analyzed through the Database program on 'the Annals of the Joseon Dynasty' and 'the Emollment of Haegoeje', two of the finest examples of classical historical records. The total number of articles on the outbreak of the hwangchung is 261 in the Annals of the Joseon Dynasty and 65 in the Emollment of Haegoeje. There were four peaks by hwangchung throughout the Joseon Era. Among them, the periods of King Taejo to King Sejong had the highest incidence. By comparing the number of records of the hwangchung from the Annals of the Joseon Dynasty with that in the Emollment of Haegoeje during the same period, results show the former was less than the latter, 35 vs 65. However, both records were relatively inconsistent with each other. Insect pests in forests as well as in agriculture were included in the biological identities of the hwangchung in the Joseon Dynasty periods, which is in accordance with those of Saigo's. The taxonomic identity could be confirmed in only 25 cases (9.5%) among the articles on hwangchung. It largely coincided with Paik's opinion: II in armyworm, nine in moth larva, one in rice stem borer, two in migratory locust, one in planthopper and one in rice-plant weevil. Therefore, it is not reasonable to regard hwangchung as a migratory locust or grasshopper only. The number of reports on the occurrence of hwangchung in the Annals of the Joseon Dynasty was 173 (66% of the total) and 47% of them were just simple reports, which means the report itself on the appearance of hwangchung was very significant. The reports on controlling insect pests were of low frequency, in 20% (34 cases) of the total reports, capturing insect pests or holding traditional ceremony called 'Poje'. Among them, only one case related to the treatment of seeds to prevent the damage by hwangchung was published in the King Sejong period. There were 37 discussions about changes and management of government policies due to disasters by hwangchung. They were mostly about relief or tax cut to the people who suffered damage and about cancellation of recruiting people to military training, constructing castles, and so on. It seems that not only the people but also the king was influenced by the hwangchung. In the case of King Seongjong, he referred to the stress of the prevention measure of locusts in 10 articles. The damage also had an effect on abdication in the reign of King Jeongjong.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.472-477
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• 2018

"Hyangcheola" is a new japonica rice variety developed as a cross between "Joryeong" and "Seolhyangchal" by the rice breeding team at NICS in 2014. The heading date of "Hyangcheola" is July 28 in the middle plain area, which is 8 days earlier than that of "Hwaseong." "Hyangcheola" has a 76 cm long culm, which is 8 cm shorter than "Hwaseong" and has 86 spikelets per panicle. The viviparous germination rate of "Hyangcheola" was 27.9%. It showed resistance to stripe virus but susceptibility to bacterial blight (K1, K2, and K3 races), dwarf and black streak dwarf viruses and planthoppers. The milled rice of this variety exhibits translucent and medium short grain shape. The protein content of "Hyangcheola" was 8.2%, which was 1.5% higher than that of "Hwaseong." "Hyangcheola" is a rice with a fragrant aroma. The content of iron in 100 g of brown "Hyangcheola" rice was 15.12 mg, which is 3.69 mg higher than that of "Hwaseong," and the zinc content was 32.24 mg, which is 8.75 mg more than that of the comparative variety "Hwaseong." The average milled rice yield of "Hyangcheola" was 4.8 MT/ha at our sites under ordinary cultivation (Registration No. 6807).

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.490-496
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• 2018

"Samkwang1," a japonica rice variety, was developed as a cross between "Samkwang" and F1 of Suwon152 (IT008283), which has a medium maturing and lodging resistance and Samkwang (IT284608), a high quality variety with bacterial blight resistance and mid-late maturing property by the rice breeding team at NICS in 2015. The heading date of "Samkwang1" was August 8 in the middle plain area, which was 2 days early than that of "Hwaseong." "Samkwang1" had a culm length of 77 cm, which was 7 cm shorter than that of "Hwaseong," and it had 128 spikelets per panicle. The viviparous germination rate of "Samkwang1" was 2.1%. "Samkwang1" showed resistance to blast, bacterial blight (K1, K2, and K3 race) and stripe virus, but was susceptible to the K3a race of bacterial blight, dwarf and black streak dwarf viruses, and plant hoppers. The milled rice of this variety exhibits translucent and medium short grains. The cooked rice grains of "Samkwang1" have an excellent palatability index (0.35) and lower protein content (6.2%) than that of "Hwaseong." The characteristics related to grain milling were better than those of "Hwaseong," especially the head rice milling recovery ratio and head rice ratio (94.2%). "Samkwang1" showed 5.62 MT/ha of milled rice productivity at 11 sites under ordinary cultivation conditions (Registration No. 6798).

• Korean journal of applied entomology
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• v.14 no.3 s.24
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• pp.97-109
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• 1975

In an attempt to develop an effective integrated system of controlling blast disease of rice caused by Pyricularia oryzae Cav., the possibility of minimizing the disease incidence by proper application of fertilizers has been investigated. Thus the effect of silicate, nitrogen, phosphorus and potassium fertilizers on the development of blast disease as well as the correlation between the rice varieties an4 strains of P. oryzae were studied. The experiments were made in 1971 and 1973 by artificial inoculation and under natural development of the blast disease on rice plants. The results obtained are summarized as follows. 1. Application of silicate fertilizer resulted in the increase of silicate as well as total sugar and potassium content but decrease of total nitrogen and phosphorus in tile leaf blades of rice plants. 2. The ratios of total C/total N. $ SiO_2/total$ N, and $K_2O/total$ N in leaf blades of rice plants increased by the application of silicate fertilizers. There was high level of negative correlation between the ratios mentioned above and the incidence of rice blast disease. 3. Application of silicate fertilizer reduced the incidence of rice blast disease. 4. The over dressing of nitrogen fertilizer resulted in the increase of total nitrogen and decrease of silicate and total sugar content in leaf blades, thus disposing the rice plants more susceptible to blast disease. 5. Over dressing of phosphorus fertilizer resulted in the increase of both total nitrogen and Phosphorus, and decrease of silicate content in the leaf blades inducing the rice plants to become more susceptible to blast disease. 6. Increased dressing of potash resulted in the increase of silicate content and $K_2O/total$ N ratio but decrease of total nitrogen content in leaf blades. When potassium content is low in the leaf blades of rice plants, the additional dressing of potash to rice plant contributed to the increase of resistance to blast disease. However, there was no significant correlation between additional potassium application and the resistance to blast disease when the potassium content is already high in the leaf blades. 7. When four rice varieties were artificially inoculated with three strains of P. oryzae, the incidence of blast disease was most severe on Pungok, least severe on Jinheung and moderate on Pungkwang and Paltal varieties. 8. Disease incidence was most severe on the second leaf from top and less sever on top and there leaf regardless of the fertilizer application when 5-6 leaf stage rice seedlings of four rice varieties were artificially inoculated with three strains of P. oryzae. 9. The pathogenicity of three strains of P. oryzae was in the order of $P_1,\;P_2,\;and\;P_3$ in their virulence when inoculated to Jinheung, Paltal, Pungkwang varieties but not with Pungok. The interaction between strains of P. oryzae and rice varieties was significant.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.600-605
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• 2011

'Boseogheugchal', a new black pericarp glutinous rice cultivar (Oriza sativa L.), was developed by the rice breeding team of National Institute of Crop Science, RDA, Suwon, Korea during the period from 1997 to 2008 and released in 2008. It was derived from a cross between SR18638-B-B-B-18-2/ Heugmi H31. The maturity of this cultivar is about 135 days from seedling to heading. This cultivar has about 12 tillers per hill and 94 spikelet numbers per panicle. Ripening ratio is about 72% and 1000 grain weight is 21.6 g in brown rice. This new variety shows grain shattering resistance and susceptible for blast, bacterial leaf blight and stripe virus. 'Boseogheugchal' has glutinous endosperm and low protein contents. It has higher anthocyanin content compared to black pigmented check cultivar 'Hegjinjubyeo'. The yield performance of brown rice was 4.82 MT/ha in local adaptability test for three years. 'Boseogheugchal' is adaptable to central plain area of Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.8 no.1
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• pp.129-177
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• 1970

For the purpose of establishing the systematized technical scheme of the cooperative rice cultivation which has most significant impact to improve rice productivity and the farm management, the author have studied the cultivation practices, and the variation of rice growth and yield between the cooperative rice cultivation and the individual rice cultivation at random selected 18 paddy fields. The author also have investigated through comparative method on the cultivation practices, management, organization and operation scheme of the two different rice cultivation methods at 460 paddy fields. The economic feasibility has been ana lysed and added in this report. The results obtained from this study are summarized as follows; 1. In the nursery, the average amount of fertilizer application, especially, phosphate and potassium, and the frequency of chemicals spray for the disease, insect and pest control at the cooperative rice cultivation are significantly higher than those of the individual rice cultivation. 2. The cultivation techniques of the cooperative rice farming after the transplanting can be characterized by a) the earlier transplanting of rice, b) the denser hills per unit area and the lesser number of seedlings per hill, c) the application of larger quantities of fertilizer including nitrogen, phosphate and potassium, d) more divided application of fertilizers, split doses of the nitrogen and potassium, e) the increased frequencies of the chemicals spray for the prevention of disease, insect and pest damages. 3. The rate of lodging in the cooperative rice cultivation was slightly higher than that of the individual rice cultivation, however, the losses of rice yield owing to the occurrence of rice stem borer and grass leaf roller in the cooperative rice cultivation were lower than that of the individual rice cultivation. 4. The culm length, panicle length, straw weight and grain-straw ratio are respectively higher at the cooperative rice cultivation, moreover, the higher variation of the above factors due to different localities of the paddy fields found at the individual rice cultivation. 5. The number of panicles, number of flowers per panicle and the weight of 1, 000 grains, those contributing components to the rice yield were significantly greater in the cooperative rice cultivation, however, not clear difference in the maturing rate was observed. The variation coefficient of the yield component in the cooperative cultivation showed lower than that or the individual rice cultivation. 6. The average yield of brown rice per 10 are in the cooperative rice cultivation obtained 459.0 kilograms while that of the individual rice cultivation brought 374.8 kilograms. The yield of brown rice in the cooperative rice cultivation increased 84.2 kilogram per 10 are over the individual rice cultivation. With lower variation coefficient of the brown rice yield in the cooperative rice cultivation, it can be said that uniformed higher yield could be obtained through the cooperative rice cultivation. 7. Highly significant positive correlations shown between the seeding date and the number of flowers per panicle, the chemical spray and the number of flowers per panicle, the transplanting date and the number of flowers per panicle, phosphate application and yield, potassium application and maturing rate, the split application of fertilizers and yield. Whilst the significant negative correlation was shown between the transplanting date and the maturing rate 8. The results of investigation from 480 paddy fields obtained through comparative method on the following items are identical in general with those obtained at 18 paddy fields: Application of fertilizers, chemical spray for the control of disease, insects and pests both in the nursery and the paddy field, transplanting date, transplanting density, split application of fertilizers and yield n the paddy fields. a) The number of rice varieties used in the cooperative rice cultivation were 13 varieties while the individual rice cultivation used 47 varieties. b) The cooperative rice cultivation has more successfully adopted improved cultivation techniques such as the practice of seed disinfection, adoption of recommended seeding amount, fall ploughing, application of red soil, introduction of power tillers, the rectangular-type transplanting, midsummer drainage and the periodical irrigation. 9. The following results were also obtained from the same investigation and they are: a) In the cooperative rice cultivation, the greater part of the important practices have been carried out through cooperative operation including seed disinfection, ploughing, application of red soil and compost, the control of disease, insects and pests, harvest, threshing and transportation of the products. b) The labor input to the nursery bed and water control in the cooperative rice cultivation was less than that of the individual rice cultivation while the higher rate of labor input was resulted in the red soil and compost application. 10. From the investigation on the organization and operation scheme of the cooperative rice cultivation, the following results were obtained: a) The size of cooperative rice cultivation farm was varied from. 3 ha to 7 ha and 5 ha farm. occupied 55.9 percent of the total farms. And a single cooperative farm was consisted of 10 to 20 plots of paddies. b) The educational back ground of the staff members involved in the cooperative rice cultivation was superior than that of the individual rice cultivation. c) All of the farmers who participated to the questionaires have responded that the cooperative rice cultivation could promise the increased rice yield mainly through the introduction of the improved method of fertilizer application and the effective control of diseases, insects and pests damages. And the majority of farmers were also in the opinion that preparation of the materials and labor input can be timely carried out and the labor requirement for the rice cultivation possibly be saved through the cooperative rice cultivation. d) The farmers who have expressed their wishes to continue and to make further development of the cooperative rice cultivation was 74.5 percent of total farmers participated to the questionaires. 11. From the analysis of economical feasibility on the two different methods of cultivation, the following results were obtained: a) The value of operation cost for the compost, chemical fertilizers, agricultural chemicals and labor input in the cooperative rice cultivation was respectively higher by 335 won, 199 won, 288 won and 303 won over the individual rice cultivation. However, the other production costs showed no distinct differences between the two cultivation methods. b) Although the total value of expenses for the fertilizers, agricultural chemicals, labor input and etc. in the cooperative rice cultivation were approximately doubled to the amount of the individual rice cultivation, the net income, substracted operation costs from the gross income, was obtained 24, 302 won in the cooperative rice cultivation and 20, 168 won was obtained from the individual rice cultivation. Thereby, it can be said that net income from the cooperative rice cultivation increased 4, 134 won over the individual rice cultivation. It was revealed in this study that the cooperative rice cultivation has not only contributed to increment of the farm income through higher yield but also showed as an effective means to introduce highly improved cultivation techniques to the farmers. It may also be concluded, therefore, the cooperative rice cultivation shall continuously renovate the rice production process of the farmers.