• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.4
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• pp.366-374
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• 2009

To determine the optimum operating conditions of the indented cylinder length grader based on varietal characteristics, broken rice removal capabilities were measured on the milled rice of 41 varieties at different conditions consisted of 3 types of indented cylinders with different indent-opening diameters and 3 different collecting-angles of broken rice. The broken rice removal capabilities were swayed by the indent's opening diameter and depth as well as the angle of the collecting trough of broken rice on the point of instrument, and by the kernel length and width as well as 1000 grain weight of milled rice on the point of rice variety. When the angle of broken rice collecting-trough reached to near the horizontal center line of the indented cylinder on the direction of upward turning side, which was referred $0^{\circ}$ in this paper, the amount of rice collected in trough increased, whereas the loss of head rice also increased. Considering the removal rate of broken rice as well as loss of head rice, it was thought that the suitable angle of trough for broken rice collecting was located $5^{\circ}$ to $15^{\circ}$ depending on varietal characteristic and indent opening diameter. It was thought that 4.2 mm or more of indent opening diameter was recommendable for the rice varieties having heavier 1000 grain weight than 22.3g, as well as larger sizes than 2.9 and 5.2 mm in width and length of rice kernel, respectively; 3.8 mm for the small-sized thin kernels, and a proper diameter between 3.8 and 4.2 mm for short to middle kernels. The varieties with relatively shorter length compared to width of kernel were more difficult to separate the broken rice than the opposite ones. For effective separation of that, it seems that some specific indent shapes such as wider opening and shallow depth etc. are required. When the broken rice content were excessively high, wider diameters of indent openings than specified sizes were thought to be the better.

• Journal of the Korean earth science society
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• v.41 no.1
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• pp.19-30
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• 2020

To understand the impact of typhoons on Gamji gravel beach Taejongdae in Busan, we carried out beach profiling using a VRS-GPS system and a Drone photogrammetry for the typhoons 'Kong-rey' invaded in October 2018 and 'Danas' in July 2019. In addition, grain sizes are analyzed to investigate the overall distribution pattern of gravels on the beach, and the beach topography is surveyed periodically to confirm the recovery rate of the beach. Grain-size analysis reveals that mean gravel sizes, in general, become finer from -6.2Φ to -5.4Φ towards the east in the seashore line direction. Variation in mean sizes is obviously observed in the cross-shore direction. Gravels in the swash zone are relatively fine about -4.5Φ in size and equant in shape, whereas the coarse and oblate gravels ranged from -5Φ to -6Φ are found in the berm. Gamji gravel beach particularly has two lines of berms: a lower berm situated facing beach and an upper berm about 10 m landward. After the typhoon Kong-rey passed by, about 1.4 m of severe erosion in upper berm occurred, and the berm eventually disappeared. On the backshore of the upper berm about 50 cm of erosion took place so that the elevation became lower. However, tangible erosion was not observed in the lower berm. When typhoon Danas hit, rated as mild storm, both upper and lower berm were eroded out. However, about 50 cm of deposition occurred only in the backshore. Only three days later, the new lower berm was formed, meaning that sedimentation rate must be high. This result indicates that Gamji gravel beach is recovered very fast from erosion caused by the typhoons when it is under the fair-weather condition even though beach morphology changes dramatically in a short period of time. Gravel beach is estimated to be or evaluated very resilient to typhoon erosion.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.17
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• pp.79-114
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• 1974

Experiments were conducted to clarify the variations of the ecological characteristics under different day-length and temperature conditions inperilla varieties from 1972 to 1973 in the experimental fields of Crop Experiment Station, O.R.D, Suwon. Thirty-six varieties were tested in the field in 1972 under 6 growing seasons differing seeding dates. from April 5th to June 20th with 15-day interval between each seeding. Pot-experiment also were conducted in 1972 and 1973. The seeds of the 6 varieties tested were sown on May 25th. In this pot-experiment natural condition was regarded as a short-day treatment and 100-W incandescent lamps were used for long-day treatment. Three selected varieties were grown under different. temperature treatments in phytotron in Crop Experiment Station. The results obtained are summarized as follows: 1. Most varieties tested flowered around September 6. The days required to flower were shortened gradually as the planting time was delayed. 2. The varieties used were matured around October 6, but the maturity was shortened when planted early. The days required for maturity after flowering was 26 to 30. 3. The growing period was also shortened gradually when planting time was delayed. 4. Plant height was reduced when planting time was delayed. 5. There were little differences in number of valid branches among planting time I, II and III, while the branch number was reduced as the planting time was delayed. 6. The dry matter weight was gradually increased from planting time I to III, while it was rapidly decreased after planting time IV. 7. It was found that the flowering of perilla was little affected by temperature. The varieties, however, were more sensitive to day-length. 8. No clear tendency was found in the plant height, number of valid branches and dry matter weight by the time and period of day-length and temperature treatments. 9. The highest yield was obtained at planting time III(May 5th) and the yield was decreased at either earlier or later planting. 10. 1, 000 grain weight appeared to be heavier as the planting time was delayed. 11. The number of flower cluster was largest at planting time III (May 5th) and it was decreased as planting time was earlier or later than III. 12. The oil content was also highest at planting time III (May 5th). 13. Days to flowering, days to maturity and total growing period and flowering period did not affect the yield much. 14. The number of valid branches, flower clusters, 1, 000-grain weight and dry matter weight were positively correlated with yield. The relationship between these characters and yield were variable depending upon the planting time.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.4
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• pp.283-289
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• 2016

This study was carried out to identify the optimum seeding dates for selecting a double-cropping system and to assess the effect of polyethylene film mulching on the yield of Proso millet. Seeds of the varieties Hwanggeumgijang and Ibaegchal were sown in Miryang on five different dates: 1st (May 25), 2nd (June 15), 3rd (June 25), 4th (July 5), and 5th (July 15), with and without polyvinyl mulching. The varieties have different characteristics, for example, Hwanggeumgijang is an early-maturing type and more sensitive to temperature, whereas Ibaegchal is a medium-maturing type and more sensitive to the duration for which it is exposed to sunlight. Late-sown Hwanggeumgijang had a short heading date from seeding and required a low accumulated temperature. It also had a shorter period of heading, a shorter culm length and a shorter diameter of stem. In contrast, it had had a higher number of ears $per\;m^2$ although similar ear length and similar 1000-grain weight. The yield potential of Hwanggeumgijang was found to decrease at a late seeding date. In particular, it significantly decreased at the seeding date of July 15. In the case of cultivation with polyvinyl mulching, the period of heading was shorter by 2-4 days and the yield potential was increased by approximately 12-32%. The length and diameter of culm in Ibaegchal were slowly decreased, but the length of ear, the 1000-grain weight and the yield potential were similar for all seeding dates (except July 15) and cultivation with and without mulching. When sown late, the length and diameter of the culm of Ibaegchal very rapidly decreased by the July 15 seeding date. The protein content of Ibaegchal was higher but the amlyose content of Ibaechal was lower compared to Hwanggeumgijang. At late seeding dates, the protein contents of the two varieties increased but the amylose contents were similar.

• Korean Journal of Weed Science
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• v.9 no.1
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• pp.1-15
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• 1989

The seventeen barnyardgrass [Echinochloa crus-galli (L.) Beauv.] accessions, which were collected national-widely in 1986 and selected two times through 1987, were experimented at 1988. To identify the ecological properties of the collected accessions of native barnyardgrass species as a weed, the experiment was conducted with Wagner pots in size of I/500a and under PE film house. 1. Accessions were classified into 5 specific groups in plant type properties by use of data from plant height, number of maximum tillers, erectness, culm length and panicle type, among others. 2. As for species identification, they were clustered into 3 similar groups and 2 individual species by use of data from color, first-glumer type, and erectness. 3. Four groups were identified for elongational properties by plant height of 22 days old seedling, length of culm, panical, leaf length and width, and inter-node and spikelet, among others. 4. Properties on quanititative growth were classified into 4 groups and 1 individual accession corresponding to differential plant height of 22 days old seedling, length of culm, panical, inter-node, leaf-sheath, spikelet, first-glumes length, grain, number of tillers, spike, and grain weight. 5. Due to different daily increasing rate in seedling height, dry weight, number of tillers and ratio in dry weight to plant height, the growth rate properties were clustered into 4 groups and one individual accession. 6. Properties on seedling growth were classified into 4 groups by use of differential date in length and width of first-leaf, plant height, number of tillers, and dry weight of young and medium aged seedling. 7. Responding to heading date, the accessions were classified into 3 groups : temperative sensitive, medium, and short-day length sensitive types, respectively. 8. By integrating of all quanititative and attributable characters, the seventeen accessions were clustered into 4 groups and 2 individual accessions.

• Korean Journal of Weed Science
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• v.30 no.3
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• pp.300-307
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• 2010

Greenhouse experiment was conducted to evaluate tolerance of six rice cultivars, three Indica${\times}$Japonica rice (long grain, cv. Dasanbyeo, Segejinmi and Hanareumbyeo) and three Japonica rice (short grain, Nampyung, Ilpumbyeo and Junamjosaeng) cultivars, to mesotrione+pretilachlor (MP) and bensulfuron-methyl+mesotrione+pretilachlor+pyriftalid (BMPP) in transplanting rice. Two herbicides were applied at 90 g and 180 g a.i. $ha^{-1}$ to three to four leaf stage rice at 5 and 15 days after transplanting, respectively. Related study was also conducted to compare $GR_{50}$ for Indica${\times}$Japonica and Japonica rice cultivars at different MP rates. Response to two herbicides varied with respect to rice cultivars and herbicide rates. All Indica${\times}$Japonica rice cultivars exhibited susceptible to both MP and BMPP as reflected by increased visual injury, shorter plant height and higher plant dry matter reduction when compared with nontreated rice cutlivars. The degree of foliar chlorosis by MP at 90 g a.i. $ha^{-1}$ was 5~6 at 7 days after treatment(DAT) but it was decreased to 3~6 at 14DAT. The degree of leaf chlorosis treated with 180 g a.i. $ha^{-1}$ MP was 6~7 at 7DAT and it was also decreased to 3~8 at 14 DAT. The plant hight of Indica${\times}$Japonica rices was inhibited by 18~43% at application of 90 g a.i. $ha^{-1}$ MP and 30~50% at 180 g a.i. $ha^{-1}$ MP. The dry matter reduction was greater than that of plant height inhibition, showing 46~73% at 90 g a.i. $ha^{-1}$ MP and 65~82% at 180 g a.i. $ha^{-1}$ MP. Similar leaf chlorosis injury and growth inhibition of rice cultivars was observed in the BMPP treatment. The injury and growth inhibition by MP and BMPP increased with increase in herbicide rate from 90 g a.i. $ha^{-1}$ to 180 g a.i. $ha^{-1}$. However, most of the Japonica cultivars are tolerant to MP and BMPP at both rates. There was no visible leaf chlorosis but plant height and dry matter production were slightly reduced at 180 g a.i. $ha^{-1}$. Based on $GR_{50}$ value determined in reduction of shoot dry weight for MP, the Indica${\times}$Japonica rice showed 12.9 fold lower compared with the Japonica rice. The result indicates that rice cultivars vary in tolerance to herbicides of MP and BMPP and Indica${\times}$Japonica rices were more susceptible than the Japonica rices to the MP and BMPP.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.324-327
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• 2008

'Onnuri' is a japonica rice cultivar developed from the cross between 'Milyang 165' and HR14732-B-67-2-3 at Honam Agricultural Research Institute (HARI), NICS, RDA, in 2005. This cultivar has a short grain shape and about 121 days growth duration from transplanting to harvesting in Korean climate condition. In reaction to biotic and abiotic stresses, it shows resistance to blast, bacterial blight pathogen from $K_1$ to $K_3$ and stripe virus, but susceptible to other major diseases and insect pests. The milled kernel of 'Onnuri' is translucent with non-glutinous endosperm. It has about 18.6% of amylose content and better palatability of cooked rice compared with 'Chucheongbyeo' cultivated in Kyunggi province. The milled rice yield of 'Onnuri' is about 5.94 MT/ha under the standard fertilizer level of the ordinary transplanting cultivation. 'Onnuri' would be adaptable to southern plain of Cheonan, middle-northern plain, and southern mid-mountainous of Korea.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.288-291
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• 2009

A new commercial rice variety "Donghaejinmi" is a japonica rice (Oryza sativa L.) with lodging resistance and high grain quality. It has been developed by the rice breeding team of Yeongdeog Substation, National Institute of Crop Science (NICS), RDA. This variety was derived from a cross between "Milyang 64" as a resistance source of brown planthopper (Bph) and "Milyang 165" as grain quality source. The donor parent, "Milyang64" has been backcrossed three times with recurrent parent, "Milyang165" and selected by the pedigree breeding method. The pedigree of "Donghaejinmi", designated as "Yeongdeog 41" in 2003, was YR21259-B-B-68-1. It has a short culm length with 69 cm and medium-late growth time. This variety is resistant to stripe virus and moderately resistant to leaf blast disease with durable resistance. It also has tolerance to unfavorable environment such as cold, dried wind and storm. Milled rice kernel of "Donghaejinmi" is translucent, clear in chalkness and good at eating quality in panel test. The merit of this variety is high head rice ratio, which is essential element to produce an article of superior quality rice brand. The yield potential of "Donhaejinmi" in milled rice is about 6.05 MT/ha at ordinary fertilizer level of local adaptability test. This cultivar would be adaptable to Yeongnam inland plains and eastern costal area of Yeongnam province.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.328-332
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• 2009

A new malting barley variety, "Oreum", was developed from the a cross between 'Kinuyutaka' and 'Samdobori' at the Honam Agricultural Research Institute (HARI) in 2006. An elite line, YMB2077-2B-24-1-2, was selected in 2003 and designated as 'Milyang132'. It showed good agronomic performance in the regional adaptation yield trials (RYT) from 2004 to 2006, and was released with the name of "Oreum" having high yielding and BaYMV resistance. The average heading and maturing dates of "Oreum" were April 18 and May 24, which were 2 days later than 'Jinyang', a leading variety, at RYT. "Oreum" had longer culm length (75 cm), more spikes per $m^2$ (990), and lighter 1,000 grain weight (35.2 g) than those of 'Jinyang' in paddy field conditions. It was showed resistance to BaYMV at the regions of Naju, Jinju and Milyang but moderate resistance at Iksan. However, the response to other environmental stresses of was similar to 'Jinyang' The yield potential of "Oreum" was about 5.43 MT/ha, 4.93 MT/ha in upland and paddy fields which was about 80%, 35% higher than Jinyang in the regional adaptation yield trials (RYT), respectively. It has good malting quality including high grain assortment, germination capacity ratio, water sensitivity and high the malt production and the extract and short filtration speed than those of 'Jinyang'.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.443-446
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• 2008

'Gangbaek' is a japonica rice variety developed and registered by the rice breeding team of Department of Rice and Winter Cereal Crop, NICS, RDA in 2006. 'Gangbaek' was derived from a cross between 'Suweon345' with good grain quality and 'DV85' resistant to bacterial blight, $K_{3a}$. $F_1$ plants were grown in the greenhouse in winter of 1992/1993 and backcrossed with 'Suweon345' as the recurrent parent. Plants resistant to $K_{3a}$ race of bacterial blight (BB) were selected from $BC_1F_1$ to $BC_4F_1$ and used as parents in the backcrossing processes. This variety has about 120 days growth duration from transplanting to harvesting in west-southern coast and Honam plain of Korea. It is about 69 cm in culm length and tolerance to lodging. In reaction to biotic and abiotic stresses, it shows moderately resistance to blast, and resistance to bacterial blight pathogen, $K_1$, $K_2$, $K_3$ and $K_{3a}$, but susceptible to other major diseases and insect pests. The milled rice of 'Gangbaek' exhibits translucent, relatively clear non-glutinous endosperm and midium short grain. It has lower amylose content of 18.6% and protein content of 6.4% compared with 'Nampyeongbyeo'. The milled rice yield performance of this variety is about 5.28 MT/ha in local adaptability test for three years. This cultivar would be adaptable to the bacterial blight-prone area in the south-western coastal and Honam plain of Korea.