• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.437-443
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• 1995

Concerns on use of excess amount of chemical fertilizier and pesticide in current farming system turns both of the producer and consumer of agricultural products to an organic farming which use a less chemicals and more natural manure. Rice-duck farming system is one of the strategy to meet the purpose and this experiment was carried out to find the effect of the rice-duck farming system on the quality and yields of rice. 20day-old rice seedling were mechanically transplanted in sandy-loam paddy field and 21 day-old ducks were raised from 3 weeks after transplanting with population of 30 heads per 10a. The plots were consists of reduce fertilizer(70%) with and without duck-raising. The conventional fertilizer treatment without duck-raising was used as check. The results obtained are summarized as follows. The weeds population of test plots which were raised with duck for 3 consecutive years was less than that of test plots without duck-raising, though a speciffic population of Echinochola crusgallis were increased. The weed control effect was higer in duck-raising than in check at the maximum tillering stage but, not at later stages of rice plant. It was found that the small animals and insects inhibiting in the rice field were reduced by duck-treatment, however, there were also damages of grass leaf roller at booting stage in the plots of duck-raising. In rice-duck plot, dark green leaf color were found: 41.8 of SPAD value than 38.6 of SPAD in check plot. Higher root activity and surface soil oxidation were also observed in rice-duck plot than check plot. 3% of the increase in yield was observed by duck-treatment. However, the expected increase of the palatability wsa not observed. This may be due to the unfavorable weather conditions during the rice growing in this expriment.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.225-225
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• 2017

This study is to investigate the effect of split application and adapted fertilization application cultivation in stable medicinal herbs production of Acorus graminens S. And it accomplished one's purpose to GAP guide manual established standard method of cultivation technology, contribute to the enlargement of farm's income. Method of fertilization application were conducted under five condition compose to standard application(N-P-K-Compost: fermented mixed oil cake fertilizer applied at $4-2-6-300kg.10a^{-1}$, twofold application(N-P-K-Compost applied at $8-4-12-600kg.10a^{-1}$) cultivation. Compost (fermented mixed oil cake fertilizer) and fused phosphate applied at 100% of basal fertilizer in April 14. The split application level of standard application and twofold application(N-K) applied at 100%, 50%, 40% of basal fertilizer in April 14, 50% and 40% of top dressing were three times application (N-K) in June 1, July 15, August 15, 25% and 20% respectively. Transplanting with Naju varieties in May 12 by growing pot seedling for 40 days in 2015. Planting density were spaced 30 cm apart in rows 30 cm apart with black vinyl mulching on open cultivation. Plot design randomized block 3 repetition. Therefore, growth characteristics by 50% and 40% of top dressing were three times application (N-K) compared to standard application and twofold application (N-K) applied at 100% basal fertilizer, aerial part as a result were so many such amount of growth as number of leaf per plant, etc., Length of diameter and main root of subterranean part growth increment rising highest. Dried roots yields treated standard fertilizer 100% application($250kg.10a^{-1}$) compared to 100% from twofold application (N-K) applied at 50% basal fertilizer, 50% and 40% of top dressing were three times application increased by 16%, 20%. respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.6
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• pp.499-505
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• 1992

This experiment was carried out to find out the optimum application method of slow-release fertilizer under different soil textures, clay loam(Deogpyeong series), sandy loam (Gangseo series) in the southern region(Milyang, Kyeongnam) of Korea. The fertilizers used were Chosun slow-release fertilizer(silicate latex coated fertilizer: N-P$_2$O$_{5}$-K$_2$O=18-12-13) and Meister 15 (thermoplastic resin coated fertilizer : N-P$_2$O$_{5}$-K$_2$O=14-14-14). The two whole basal application methods such as side band placement at transplanting time of rice plant(cv.Donghaebyeo) and incorporation with soil as basal were tested. The released amount of ammonium nitrogen from the soils for 4 days submerged was 95ppm in sandy loam and 60ppm in clay loam. The greenish degree of rice leaf was higher at the whole plow layer placement method than the others. The nitrogen efficiencies of the fertilizers were Meister 15 > convention > Chosun in order and between the application methods were similiar. The growth status was better at the whole plow layer placement application method of Meister 15 regardless of soils and seedling ages. The ripening ratio was increased at slow-release fertilizer application, and between application methods, whole plow layer placement was lower because of lodging damage. The yield in clay loam soil showed a significant difference between the ferilizers, but there were slight differences between the application methods and fertilizers in sandy loam soil. As a result, the slow-release fertilizer, Meister 15, applied at the whole layer showed a good rice growth and seemed a plausible fertilizing method.

• Korean journal of applied entomology
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• v.21 no.3 s.52
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• pp.153-158
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• 1982

The study was conducted to obtain the basic information on the diseases epidemics of vegetable crops grown in Namji, Jinju, Gimhae and Suncheon under the extremely varied and specified conditions, plastic film house. The disease survey was conducted from the end of April, 1951 to April 1982. Leaf mold and late blight were serious foliar disease in tomato during the seedling stage, especially when the infected seeds were sown. The diseases increased rapidly 35 days after seeding. In both continuous cultivation of cucumber and rotation with upland crops, incidence of Fusarium wilt was severe while incidence of the disease was negligible in cultivations after paddy rice or grafting on pumpkin. Downy mildew of cucumber was severe in Jinju and Suncheon area, however, it was not so serious in Namji area where the growing season of cucumber was unfavorable for the maximum disease incidence. Cucumber mosaic virus disease was prevalent in the areas surveyed and the disease incidence was increased rapidly after June. Powdery mildew prevailed at the early stage of cucumber growth after transplanting in Namji area. Root rot and wilting caused by Phytophthora capsici was as the most destructive disease in pepper grown under the vinyl house, especially in Namji and Jinju area where the pepper has been cultivated intensively. The Phytophthora attacked most parts of young plants during the winter time and then induced crown rot on the adults plants. Cultivation of pepper in vinyl house was almost impossible because of the Phytophora disease by the end of June. Virus diseases to tomato plants were prevalent throughout the surveyed area and the damage was also severe. In Jinju and Gimhae area leaf mold and late blight showed high infection rate in tomato during the harvest time.

• Korean journal of applied entomology
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• v.17 no.1 s.34
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• pp.23-28
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• 1978

The study has been carried to confirm the pathotypes of Kresek inducing isolates of X. oryzae, and its reaction to the test plants when they were inoculated by the use of various methods. Induction of Kresek symptom by 23 isolates which randomly samplified from 123 Kresek areas through the country also were examined. The specificity of Pathotypes I, II, V in causing Kresek and the potenciality of infected rice straw is a first inoculum for Kresek epidemics in nature were tested. Fifteen out of 23 isolates from kresek area belonged to pathotype group I, while the rest of 8 isolates 5 howed group II reaction, and the most of isolates were originated from infected rice plant of Milyang #23. All of five pathotype groups were abled to produce 'Kresek' symptom although they showed some differences in each group of pathotype. The varieties Milyang #21, 22 and 23 were attacked by all isolates of group I, II and V while the Gogyoku group varieties including Yushin produced kresek symptom only by pathotype group II. Infected and dried straw maintained the pathogens during the winter period, and these straw acted as a first inoculum of Kresek disease when the straw were cutted and used as a manure just before transplanting of rice seedling.

• Weed & Turfgrass Science
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• v.5 no.4
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• pp.187-190
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• 2016

This study was conducted to determine phytotoxicity of domestic rice varieties and characteristic of sensitive gene involved in herbicide reaction of 4-HPPD (4-hydroxy phenylpyruvate dioxygenase) inhibiting herbicides. The five rice varieties were grown for 2 to 3 leaf stage on seedling trays and then transplanted into plastic pot: 4-Japonica type (Sangjubyeo, Sambaekbyeo, Sanduljinmi and Kumyoung) varieties and 1-Indica type variety (IR8). We trialled standard (14 g a.i. $10a^{-1}$) and double fold (28 g a.i. $10a^{-1}$) dose of benzobicyclon treatment at 10 days after transplanting in order to investigate phytoxicity. The Japonica-type Sangjubyeo showed no rice injury but Indica-type IR8 show 4-5 (standard) and 5-6 (double fold) phytoxicity levels. In spite of Japonica-type, Sanduljinmi and kumyoung showed 3-4 and 4-5 levels. Target resistant gene, Hydroxyphenylpyruvate dioxygenase inhibitor sensitive gene No.1 (HIS1) have been isolated from five domestic rice cultivars (Sangjubyeo, Sambaekbyeo, Sanduljinmi, Kumyoung and IR8). Results of the sequence through PCR, all five tested rice cultivars had HIS1 gene regardless to rice cultivars. And the difference between rice varieties from sequence of HIS1 were identified some variation in genes.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.2
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• pp.78-84
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• 2005

This study was conducted to investigate the effects of chemical treatments and electric and magnetic field treatments on germination and seedling growth of onion (Allium cepa L.). Germination ratios of the onion seed were not much different among the tested species. However, germination ratio was much higher in species of small and medium size seed than that of large one. Moisture content of the seeds was shown to be more suitable in the range of 10-15% for seed germination compare to that of 20%. The germination ratio of onion seeds was found to be increased by the chemical treatments in the order of GA<$NaNO_3$<$KNO_3$. In particular, the treatments with 0.1 and 0.2% $KNO_3$ increased the germination ratio by 13 and 15% compared to that of the non-treatment. The seeds treated with electric or magnetic field resulted in much higher germination ratio and better initial growth. Germination ratios of 86 and 88% were found in the 10 kV and 4 Gauss treatments, respectively. The length and weight of the seedlings grown for 40 days after transplanting were increased by 23-45% with 8 kV and 12 Gauss treatments compared to those of non-treatment.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.2
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• pp.108-113
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• 2022

Arsenic (As) uptake and accumulation from agricultural soil to rice vary depending on the soil environmental conditions such as soil pH, redox potential, clay content, and organic matter (OM) content. Therefore, these factors are important in predicting changes in the uptake and accumulation of As in rice plants. Here, we studied the chemical properties of As-contaminated and/or rice straw compost (RSC)-treated soils, the growth responses of RSC-applied rice plants under As-contaminated soils, the changes in As content of soil, and the relationship between As uptake and accumulation from the RSC-treated soils to the rice organs under As-contaminated soils. Rice plants were cultivated in 30 mg kg^-1 As-contaminated soils under three RSC treatments: 0 (control), 12, and 24 Mg ha^-1. No significant differences were indicated in the chemical properties of pre-experimental (before transplanting rice seedling) soils, with the exception of EC, OM, and available P₂O₅. As the treatment of RSC under 30 mg kg^-1 As-contaminated soils increased, EC, OM, and available P₂O₅ increased proportionally in soil. Increased soil RSC under As-contaminated soils increased shoot dry weight of rice plants at harvesting stage. As content in roots increased proportionally with RSC content, whereas As content in shoots decreased under As-contaminated soil at all stages of rice plants. Nevertheless, As accumulation were significantly decreased in both roots and shoots of RSC-treated rice plants than those in the plants treated without RSC. These results indicate that the use of RSC can mitigate As phytotoxicity and reduce As accumulation in rice plants under As-contaminated soils. Therefore, RSC can potentially be applied to As-contaminated soil for safe crop and forage rice production.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.5
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• pp.383-393
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• 1991

Lodging of rice plant is the most important damage by unfavourable weather conditions in rice cultivation. High levels of nitrogen application and growing of Japonica rice variety is one factor to increase the lodging damage. Lodging of rice plant decreasing grain yield; 34% at milky. 21% at dough. 20% at yellow stage. decreasing grain Quality. increasing green rice. and increasing labor cost to harvest. To decrease lodging damage. the lodging resistant varieties will be selected and cultural practices such as amount and time of nitrogen application. planting density. water management. and disease and pest control methods have to be study for the short and strong culm. and good rooting system. Also. application methods such amount and time of plant growth regulators and new types of chemicals will be develop for the reducing lodging of rice plant. To decrease the lodging damage in direct seeding cultivation. first identifying the differences of lodging mechanisms between hand transplanting and direct seeding, second establish the suitable direct seeding methods such as seedling establishement. fertilization. and water menagement.

• Journal of Marine Life Science
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• v.3 no.1
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• pp.31-37
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• 2018

We investigated natural habitat of seagrass and created replacement habitat to monitor for restoration of the habitat which is expected to be damaged at Cheonseong harbor in Busan. Depth of water for natural seagrass habitat at Cheonseong harbor was 1.2~3.1 m and the water temperature was 7.4℃, salt concentration was 29.1 psu and pH was 8.05 in January, 2013. The density of seagrass was 167.1±16.4 shoots m^-2, the total length was 48.5±18.1 cm, the height of sheath was 9.1±2.8 cm and the width of leaf was 4.8±1.1 cm, respectively. We transplanted in December 2014 and monitored the habitat during 9 months after transplanted. In the beginning, the density of seagrass was decreased to 8.5 shoots patch^-1 in January and was increased to 19.0 shoots patch^-1 in April. The total height were 73.3±2.9~121.3±6.1 cm, the length of sheath were 9.6±0.6-21.0±1.2 cm, the width of leaf were 5.7±0.1~6.8±0.2 mm. It showed that all values were increased steadily until July and was decreased rapidly in August. Flowering shoot, which was not observed in the beginning of transplanting, started to be spotted in March and was continued to be seen during the monitoring period. We were able to observe seedling of germinated seagrass in seeds in the replacement habitat next year.