• Korean Journal of Agricultural Science
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• v.39 no.4
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• pp.473-476
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• 2012

The experiment was conducted to investigate the herbicidal efficacy of imazosulfuron mefenacet by using remote-controlled aerial application (RCAA) to control annual and perennial weeds in rice paddy field. Eight annual weed species including Echinochloa crus-galli L. and three perennial weeds were dominated in the experimental field. Application of imazosulfuron mefenacet using RCAA was highly effective to control both annual and perennial weed species. No phytotoxic effect was observed in the rice based on the plant height and the number of tillers. Finally, rice yield in the imazosulfuron mefenacet treatment was as much as that in the hand weeding. This study indicates that imazosulfuron mefenacet using RCAA can be applied to control both annual and perennial weed species in rice paddy field.

• Korean Journal of Weed Science
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• v.15 no.4
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• pp.298-304
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• 1995

This study was carried out to make the most of them as the fundamental data for reasonable weed control when population of weeds was observed in the alternated fields of lowland and upland. The annual and the perennial paddy weeds in the continuous paddy rice field remarkably decreased when compared to that in the alternated field of paddy rice and soybean. The longer was the duration of upland field condition, the less was the population of lowland weeds and the more was the population of upland weeds. Biennial weeds in the contiuous paddy rice field were less than that in the rotated field of paddy rice and soybean, and this tendency was clear in Alopecurus aequalis Sobol. In the continuous cropping of paddy rice, population of biennial weeds in the culverted field was higher than that in the unculverted one, but in the continuous cropping of soybean this tendency was vice versa.

• Journal of Korean Society of Rural Planning
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• v.8 no.1 s.15
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• pp.60-68
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• 2002

A Modified CREAMS model, CREAMS-PADDY was developed to simulate the hydrology and nutrient transport at an irrigated rice paddy. The hydrology at a paddy was simulated by a daily water balance routine which reflects daily inflow, outflow, and water level changes. The soil erosion was simulated using modified USLE. The nutrient transport for total nitrogen and phosphorus were depicted for various phases of each constitute such as extraction, percolation, mineralization, and plant uptakes. Field monitoring was conducted to investigate the water quality changes at a paddy field at three times a week during the growing season of 1996. The proposed model simulates the water quality of the paddy reasonably well, and is found to be applicable to field conditions.

• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.355-363
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• 2018

This study was conducted to investigate suitable rice cultivars for various rice based cropping systems in a paddy field in the Yeongnam plain area. Thirteen rice cultivars (5 early, 3 medium and 5 mid-late maturing cultivars) and three transplanting dates (June 5, June 25 and July 5) were evaluated in this study. The mid-late and early maturing cultivars for the July 5 and June 25 transplanting headed before August 30 which is the safe heading date in the Yeongnam plain area, ranging from Aug. 26 - 28 and Aug. 18 - 23, respectively. The safe harvest time of rice for double and triple cropping systems should be before the middle of October for the cultivation of the succeeding winter crops. The rice yield was the highest for the June 5 transplanting regardless of the rice cultivars, and it gradually decreased as the transplanting date was delayed from June 5 to July 5 due to a decrease in the spikelet numbers per panicle number and in the ripened grain rate. In contrast, the other yield parameters that include the panicle number per $m^2$, the 1,000-brown rice weight, and the ripened grain ratio were not significantly affected. The result indicates that based on the milled rice, heading time and harvest time, a medium maturing cultivar (Haiami and Samdeog) would be applicable to a winter barley/wheat, garlic/onion-summer rice double cropping, while a mid-late cultivar (Saeilmi, Saenuri and Hyunpoom) would be suitable for a spring potato/waxy corn-summer rice double cropping in the Yeongnam plain area. On the other hand, an early maturing cultivar (Unkwang, Jokwang and Haedamssal) would be preferable for a triple cropping because of the short growth period of rice.

• Korean journal of applied entomology
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• v.43 no.4 s.137
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• pp.291-296
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• 2004

Overwintering sites and Seasonal occurrence of various growth stage of the rice black bug, Scotinophara lurida BURMEISTER were studied at the rice paddy field in Chungbuk area, from 1999 to 2001. Attraction by light trap from overwintering site of overwintering adults occurred from early June to mid July and its peak was shown on late June. Eggs were oviposited from early July to early August and its peak appeared in late July. Nymphs were observed from mid July to late September with its peak on mid August. The newly eclosed rice black bugs were found in late August and its peak on mid September. The rice black bug overwintered as adult at mountain foot, banks, and rice paddy levee.

• Korean journal of applied entomology
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• v.36 no.2
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• pp.141-144
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• 1997

Studies were conducted to investigate the incidense of insect pests in transplanted and direct seeded paddy fields in southern region of Korea. Population dencities of the rice green leafhopper (RGLH: Nephotettix cincticeps Uhler) and rice leaffolder (RLF: Cnaphalocroch medinalh Guenee) were higher in machine transplanted than in direct seeded, but the brown planthopper (BPH: Nilaparvata lugens Stal) and smaller brown planthopper (SBPH: Laodelphax striatellus Fallen) were abundant in direct seeded. However, no significant difference was found between machine transplanted and direct seeded fields in the incidense of rice stem borer (RSB: Chilo suppressalis Walker), whiteback planthopper (WBPH: Sogatella furcifera Horvath), and rice stem magot (RSM: C'hlorops oryzae Matsumura). Occurrence of rice key pests were affected more by transplanting time than other cultural practices. Later transplanting induced higher populations of BPH, WBPH, SBPH, RGLH. However, RSB and RLF caused higher damage in earlier transplanted paddy field.

• Journal of Environmental Science International
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• v.30 no.8
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• pp.659-671
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• 2021

The physicochemical properties of soil and the yield and quality of rice (Oryza sativa L. cv. Sailmi) were assessed using Italian ryegrass (Lolium multiflorum Lam. cv. Kowinearly)-rice double cropping systems in the paddy fields at Goseong and Miryang in southern Korea. The average temperatures during the ripening period were approximately 1 ℃ higher than the optimal temperature for rice ripening and the sunshine duration was reduced by frequent rainfall. Consequently, it was slightly below the optimal conditions required for rice ripening. In the soil at Goseong, winter Italian ryegrass cropping increased the pH, electrical conductivity, and the contents of organic matter, total nitrogen (T-N), available P₂O₅, K, Ca, and Mg than winter fallowing. Particularly, the contents of T-N and available P₂O₅increased significantly. In the soil at Miryang, Italian ryegrass slightly increased the electrical conductivity and the T-N, Mg, and Na contents. Therefore, winter Italian ryegrass cropping improved the physicochemical properties of paddy soils; however, Italian ryegrass-rice double cropping slightly reduced the culm length at both Goseong and Miryang, without markedly changing the panicle length or number compared to fallow-rice cropping. Furthermore, at Goseong, Italian ryegrass-rice double cropping slightly decreased the spikelet number and milled rice yield, and increased the ripened grain rate; however, at Miryang, contrasting results were observed. In addition, fallow-rice cropping revealed no differences in the head rice or opaque rice rates. The protein content was slightly increased in Italian ryegrass-rice double cropping, without significant changes in the amylose content or Toyo value, compared to that in fallow-rice cropping. The peak and breakdown viscosities were slightly decreased. These results indicate that winter Italian ryegrass cropping might alter rice taste but may not exhibit remarkable negative effects on rice cultivation. Therefore, Italian ryegrass-rice double cropping system is recommended for paddy fields in southern Korea. Nevertheless, to increase the rice yield and quality, fertilization standards for rice cropping that consider the changes in the T-N and organic matter contents in paddy fields caused by winter Italian ryegrass cropping need to be established.

• Proceedings of the Korean Society of Grassland Science Conference
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• 2002.09b
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• pp.5-56
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• 2002

The problems in the current domestic forage production were evaluated, and the prospective improvement was suggested in this paper. Grassland development in forest, production of high quality forages in upland and paddy land, efficient utilization of rice straw, development of new varieties of forages suitable for our environmental conditions and imported forages were described Among them, preferential production and utilization of forages using paddy field after rice harvest . should be enlarged for domestic supply of forages in Korea. Several studies were carried out to select the promising forage crops and barley cultivars for whole crop silage production, to determine productivity, nutritive value and production cost of forages produced in paddy field, and feeding effect of forages with Hanuwoo and milking cow for whole crop silage with forages produced in paddy field, 1999 to 2001, and also discussed restraint factors and activation plans for enlargement of forage production in paddy land. The promising forage crops in paddy field were rye and barley for Middle region, and rye, barley, early maturing Italian ryegrass and wheat for Southern region. The promising barley cultivars for whole crop silage in paddy field were Albori in Suwon, Keunalbori, Milyang 92, Saessalbori, and Naehanssalbori in Iksan, and Keunalbori, Albori, Naehanssalbori, and Saegangbori in Milyang, respectively. Silage production, quality and animal palatability of silage by trench and round bale were also compared. The production yields of whole crop barley silage(WBS) were 17,135kg as a fresh matter, and 6,011kg as a dry matter per ha, and the quality of WBS was 2∼3 grade, while that of rice straw silage was 4 grade as a farm basis. The production cost of WBS per kg was 83won as a fresh matter, and 238won as a dry matter. Feeding of WBS as forages on Hanwoo was very desirable for the improvement of live-weight gain, beef quality and farm income, particularly in growing stage of Hanwoo. Milk production and income were also increased, and feed cost was decreased by feeding of WBS. The daily voluntary intake of WBS in milking cow was 26.3kg as a fresh matter(DM 7.7kg) per head. Milk production when WBS was fed, was very similar to that of imported hay feeding such as Kentucky bluegrass or domestic corn silage. The issues to be solved in near future f3r stable forage production and supply in paddy land are sustainable livestock-forages policy, development & seed production of new varieties of barley, rye, Italian ryegrass and other promising forages, efficient demand & supply system of forages, solidification for mass production and utilization of forages, efficient application management of animal slurry on paddy field considering environmental agriculture/livestock industry, and break k development of bottleneck technique in production field. Domestic production & supply of high cost agricultural machine (round baler, wrapper, handler and so on), plastic wrapping film, and silage additives are also important.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.3
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• pp.205-212
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• 2015

Farmers with forage barley (Hordeum vulgare L.)-rice (Oryza sativa L.) cropping system at reclaimed tidal lands burn crop residues to facilitate seedbed preparation or remove them for feed stock. This study was conducted to investigate the effect of rice straw amendment and N fertilization on soil properties and N uptake of rice under forage barely-rice cropping system at reclaimed tidal paddy field. Rice straw was applied at the rates of 0, 2.5 and $5.0ton\;ha^{-1}$ and N was fertilized at 0, 100, 200 and $400kg\;ha^{-1}$. Although there was no significant difference in the growth and yield of rice, fresh and dry weight of forage barely increased with increasing the amount of rice straw. The amount of N uptake of rice at harvesting stage was $65.8-69.2kg\;ha^{-1}$ by the amount of rice straw amendment, but there were no significant differences among rice straw amendment levels. After harvesting the rice, the soil salinity decreased with rice straw amendment compared to the control. After forage barely and rice cultivation, soil organic matter contents increased to $2.6-2.8g\;kg^{-1}$ and $3.2-3.5g\;kg^{-1}$, respectively. The amount of N uptake of rice at harvesting stage increased up to $82kg\;ha^{-1}$ in $400kg\;ha^{-1}$ N applied plots which were $37.8kg\;ha^{-1}$ higher than the control. Nitrogen fertilization decreased N recovery efficiency. The highest yield of rice was observed at $244kg\;ha^{-1}$ N fertilization level, but the optimum N level was estimated at $168kg\;ha^{-1}$ in order to keep the protein content of rice under 6.5%. Further researches on N uptake and application of organic matter according to soil salinity will be necessary to increase N use efficiency at reclaimed tidal paddy field.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.3
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• pp.195-198
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• 2000

Weedy rice has typical characters such as easy shattering, dormancy, and longevity. These characters let it undergo the winter and occur year by year, It is very difficult to control weedy rice once the field have contaminated with its seeds. Therefore, the control method for weedy rice was focused on the no-tillage direct seeding in this experiment. The germination ability of seeds shattered on the soil surface in the next spring was 92.7% in weedy rice, and 4.3% in cultivated rice. The possible depth of weedy rice emergence were 1.5cm, 3.0cm and 6.8cm in no-tillage, wet seeding and dry seeding paddy field, respectively. The paddy field contaminated with weedy rice was maintained as no-tillage, and then irrigated in early spring (April 15). We could induce weedy rice on the soil to emerge with irrigation, and then kill by using non-selective herbicide, paraquat. Weedy rice was controled 92.2% of total emerged by this method. After seedling establishment of cultivated rice, molinate, thiobencarb, oxadiazon, dithiopyr, butachlor were soil-applied to suppress the emergence of weedy rice seeds buried in the soil. Oxadiazon was the most effective to repress the weedy rice among soil-applied herbicides tested. The highest control value was 96.4% as the result of combination of paraquat and oxadiazon.