• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.3
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• pp.257-265
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• 2015

This experiment was carried out to determine the optimum planting density for rice pot seedling cultivation in wheat-rice double cropping system in Honam plain area. A mid-late maturing rice variety 'Chinnong' was raised in pot seedling tray and conventional tray for 30 days, and then transplanted on June 25 in 2012 and 2013. Four different planting densities (15.2, 18.9, 21.6, and 25.3 hills per $m^2$) in pot seedlings were applied as treatment. Conventional tray seedling was implicated as control at a single planting density of 27.8 hills per $m^2$. In this experiment, the number of effective tillers was increased as planting density increasing, but stem diameter was decreased. Pot seedling showed higher stem diameter and effective tillers than the control. Heading dates of pot seedling plots were not significantly different between the planting densities but 2 days faster than the control. Culm length, number of panicles, panicle length, and ripening grain ratio were higher in pot seedling compared to the control, but 1000-grain weight showed no significant difference. Milled rice yields in pot seedlings ranged from 5.19 to $5.43\;t\;ha^{-1}$, and the highest yield was observed in 21.6 hills per $m^2$. Head rice ratios in pot seedlings and the controls were not significantly different. Above results on planting density of rice pot seedling cultivation would be applicable to wheat-rice double cropping and also to late transplanting cultivation of rice single cropping.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.4
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• pp.251-258
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• 2005

This study was conducted to examine the effect of application of pig manure slurry(PMS) for rye cultivation in Paddy-land on rice productivity The field experiments were carried out from 1999 to 2002 on well-grown rice in Paddy-land at Kimje, Chunbuk province in Korea. PMS was manufactured by the fermentation for 6 months in natural condition. Amount of PMS was adjusted equal to total nitrogen value relative to its value of commercial chemical fertilizers. The amount of PMS were spread evenly over the soil surface two times; first in the autumn (before sowing, end of November) and second in the spring(regrowth of rye, middle of March). The field plots were consisted of four kinds (PMS $100\%$ treatment, PMS $200\%$ treatment PMS $100\%$ treatment with half of CF (CF $50\%$), Full of CF treatment (CF $100\%$). The experiment was designed as a randomized complete block. Each treatment was replicated three times. Rices are customarily gown under tropical korean condition as annuals. The results obtained from this study were summarized as fellows. Panicle length of rice was shorter in PMS $100\%$ than other treatments. Ripening grain ratio was the lower in CF treatment. In treatment of PMS $100\%$ and PMS $200\%$, 1000 grain weight was a downward trend as compared to that of full of CF treatments, whereas number of grains per $m^2$ was increased as compared to other treatments. Number of panicles reveals that there is an increase in order; CF $50\% + PMS\;100\%>\;PMS\;100\%\;>\;CF\;100\%\;>\;PMS\;200\%$. Yield of milled rice showed hi인 in CF $100\%$ and $CF 50\%+ PMS 100\%$, but were was no significant difference among treatments. There were did not a regular tendency in the ratio of leaf sheath bright, however the ratio of lodging area was higher in $CF50\%+PMS\;100\%$ treatment than other treatments. Based on the results of this experiment, $CF 50\%+PMS\;100\%$ may be the most effective in rice productivity under application of PMS for rye cultivation in Paddy-land.

• Journal of the Korean Magnetics Society
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• v.5 no.4
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• pp.269-274
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• 1995

The basic composition of Mn-Zn ferrite was $Mn_{0.631}Zn_{0.316}Fe_{2.053}O_{4}$(specimen A), $Mn_{0.584}Zn_{0.312}Fe_{2.104}O_{4}$(specimen B) and $Mn_{0.538}Zn_{0.308}Fe_{2.154}O_{4}$(specimen C) with additional 0.1 mol % $CaCo_{3}$ and 0.04 mol % $V_{2}O_{5}$. For high per¬meability and acceleration of grain growth, $CaCo_{3}$ and $V_{2}O_{5}$. was added. The mixture of the law materials was calcinated at $950^{\circ}C$ for 3 hours and then milled. The compacts of toroidal type were sintered at different temperature($1250^{\circ}C$, $1300^{\circ}C$, $1350^{\circ}C$) for 2 hours in $N_2$ atmosphere. The effects of the various raw material composition and sintered temperature on the physical properties of Mn-Zn ferrite have been investigated. They turned out to be spinel structure by X-ray diffraction and the size of grain from SEM was from $18\;\mu\textrm{m}\;to\;23\;\mu\textrm{m}$. As the sintering temperature was increased from $1250^{\circ}C$ to $1350^{\circ}C$, the initial permeability and magnetic induction has increased and the both of Q factor and coercive force has decreased. The coercive force and curie temperature were almost the same at each specimen Their values were about 0.45 Oe and $200^{\circ}C$. The frequency of specimen will used in the range from 200 kHz to 2 MHz. The basic composition of $Mn_{0.584}Zn_{0.312}Fe_{2.104}O_{4}$(specimen B) sintered at $1300^{\circ}C$ shows the best results at magnetic induction (Br & Bm).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.3
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• pp.210-219
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• 2021

In recent years, air temperature has been increasing rapidly compared to the 1980s because of global warming. This increase in temperature reduces the yield and quality of rice; therefore, measures are needed to prevent such effects and ensure food security. The early maturing type (EMT) of rice is mainly cultivated in the central northern mid-mountainous area (CNMA). This study was conducted to shift the transplanting date of EMT and to examine the adaptability of the mid-maturing type (MMT) or mid-late maturing type (MLMT) in the Jecheon region of the CNMA to address global warming. The air temperature increased by 0.7-0.9℃ in the 2010s, compared to that in the 1980s, and was similar to other decades during the ripening period. Over the past 35 years, considering rice quality, the heading date of the Odae variety has arrived sooner by approximately 10 days, the ripened grain ratio has increased by more than 10%, and the thousand grain weight; however, the mean temperature at 40 days after heading has increased by more than 2℃. The late marginal heading date in the Jecheon region was determined as August 11 based on the accumulated temperature of 880℃ and August 15 based on 840℃ for 40 days after heading. According to different transplanting dates, milled rice yield per 10 a was the highest at 567 kg with June 10 in EMT, 595 kg with June 10 in MMT, and 572 kg with May 30 in MLMT. Considering the late marginal heading date, rice yield, and quality, the optimum transplanting date was June 15 in EMT, June 5 in MMT, and May 30 in MLMT in the Jecheon region of CNMA. Owing to global warming, MMT and MLMT are expected to be reliably cultivated in the CNMA.

• Korean Journal of Breeding Science
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• v.43 no.3
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• pp.165-171
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• 2011

A new rice variety 'Jinbo' is a japonica rice (Oryza sativa L.) with good eating quality, lodging tolerance, and resistance to rice stripe virus (RSV) and bacterial blight disease (BB). It was developed by the rice breeding team of Yeongdeog Substation, National Institute of Crop Science (NICS), RDA in 2009. This variety was derived from a cross between 'Yeongdeog26' with good grain quality and wind tolerance and 'Koshihikari' with good eating quality in 1998 summer season. A promising line, YR21324-56-1-1, selected by pedigree breeding method, was designated as the name of 'Yeongdeog45' in 2005. After the local adaptability test was carried out at nine locations from 2006 to 2008, 'Yeongdeog45' was released as the name of 'Jinbo' in 2009. 'Jinbo' has short culm length as 74 cm and medium maturating growth duration. This variety is resistant to $K_1$, $K_2$, and $K_3$ races of bacterial blight and stripe virus and moderately resistant to leaf blast disease with durable resistance, and also it has tolerance to unfavorable environments such as cold and dried wind. 'Jinbo' has translucent and clear milled rice kernel without white core and white belly rice, and good eating quality as a result of panel test. The yield potential of 'Jinbo' in milled rice is about 5.65 MT/ha at ordinary fertilizer level in local adaptability test. This cultivar would be adaptable to middle plain, mid-west costal area, east-south coastal area, and south mid-mountainous area.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.607-611
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• 2009

"Jongnambyeo", a new japonica rice cultivar(Oryza sativa L.), is a mid-late maturing ecotype developed by the rice breeding team of National Yeongnam Agricultural Experiment Station(NYAES) in 2001 and released in 2002. This variety originated from the cross of Milyang96/YR12734-B-B-22-2(in 1991/1992 winter) and was selected by means of a mixed method of bulk and pedigree breeding. The pedigree of Junambyeo, Milyang 169 designated in 1999, was YR15161-B-B-B-57-2-3. It has about 79cm in culm length and tolerant to lodging. And this variety is resistant to bacterial leaf blight($K_1$), stripe virus and moderately resistant to leaf blast disease. Milled rice kernels of "Jongnambyeo" is translucent with non-glutinous endosperm and clear in chalkness and good at eating quality in pannel test. The yield potential of "Jongambyeo" in milled rice is about 5.60MT/ha at ordinary fertilizer level of local adaptability test. This cultivar would be adaptable to the Yeongnam plain and southern coastal of Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.35-41
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• 2006

This study was conducted to establish the post-harvest management system in rice. Harvested hulled rice was gathered into large-scale bag and combine bag, in which the rice quality and the influence on quality change were investigated on various storage periods and moisture contents. Moisture content of hulled rice ranged from 23.7% to 28.8% on different harvest times, which grew lower as harvesting time was delayed. When desiccation was retarded hulled rice in large scale bag was changed in color and emitted an of offensive odor in 3 days and that in combine bag showed similar symptom in 4 days. Inner temperature in large scale bag was changed a lot when the storage period was prolonged and also the moisture content was higher while that in combine bag increased regularly corresponding to the moisture content at the time of harvest. Moisture content of hulled rice stored in large-scale bag increased 2 days after harvest and the more moisture content showed the more increased tendency, while in the case of combine bag the moisture content was not changed much whether the hulled rice contained low or high moisture content in harvesting. As desiccation was delayed fatty acid increased much more in large-scale bag than in combine bag even though protein and amylose contentwere not changed. As desiccation was delayed more and hulled rice contained moisture more in harvesting head rice ratio of brown rice decreased and green-kerneled rice and damaged grain ratio increased and quality of milled rice also became deteriorated. As a result, desiccation day to minimize the deterioration of rice quality was estimated 1-2 days in large scale bag and 2-3 days in combine bag after harvesting.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.4
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• pp.227-233
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• 2014

This experiment was undertaken to develop triple cropping systems for winter cereal crops for forage, early maturing rice and oats, and to select a winter forage crop in order to determine rice transplanting time at paddy fields in the southern region. Also, the productivity and feed value of the resulting forage crops were examined. When winter cereal crops used for forages are first harvested at the early maturing rice transplanting period, and again harvested during the winter forage crop harvesting period, the fresh yield and dry matter yield of rye were 32.0, 42.3 ton/ha and 5.8, 16.5 ton/ha, respectively, demonstrating higher yields than other winter crops. The early maturing rice, 'Jopyeong', transplanted on June 4 had a lower percentage of ripened grain compared to those transplanted on May 6, and milled rice yield transplanted on June 4 was also decreased by 22%. Thus, the results showed that early transplanting was profitable. Regarding the oats grown during the fall cropping season, the heading date for the oats sown first was on October 10, but the heading was not observed in those sown later. Dry matter yield and TDN yield of the second sowing was less than 50% compared to the first. Consequently, rye may be the most suitable winter forage crop for triple cropping systems. Early transplanting of 'Jopyeong' after rye harvesting before April 30 in addition to timely sowing of oats in the fall season would be profitable for rice and forage production using triple cropping systems in the southern region.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.624-630
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• 2010

In order to investigate the effects of continual pre-plant application of liquid pig manure (LPM) on growth and quality of rice in double cropping system of rice and malting barley, the liquid pig manure was applied after harvesting rice and malting barley for 3 years. Field experiment was designed with non-fertilizer, chemical fertilizer (CF) 100% recommended by soil testing, rice (LPM 50%+CF 50%)+malting barley (CF 100%), rice (LPM 50%+CF 50%)+malting barley (LPM 50%+CF 50%), rice (LPM 100%)+malting barley (CF 100%) and rice (LPM 100%)+malting barley (LPM 100%). The yield of rice was increased by 13% with increasing culm length and No. of panicle per hill as 482 kg $10a^{-1}$ in rice (LPM 100%)+malting barley (LPM 100%) plot compare with 427 kg $10a^{-1}$ in rice (CF 100%)+malting barley (CF 100%) plot. Whereas, lodging index was high in rice (LPM 100%)+malting barley (LPM 100%) plot by increasing of internodes length from 3rd to 4th and decreasing of breaking strength. When the quality of milled rice was compare with rice (CF 100%)+malting barley (CF 100%) plot, it was decreased by increasing of protein contents and decreasing of rate of perfect grain in rice (LPM 100%)+malting barley (LPM 100%) plot. The content of amylose was not significant by 19.4~22.0%. Toyo-taste value was not different in LPM 100% and CF 100% plot. Rice could be grown with only liquid pig manure 100%, but considering yield and quality of rice and lodging risk, basal fertilization by LPM 50% and top-dressing by CF 50% application was recommended for rice cultivation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.4
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• pp.420-428
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• 1996

This study was conducted to investigate the response of growth and yield of rice under five different cultural methods, machine transplanting(MTNT), puddled drill seeding (PDSNT), drill seeding on soil surface (DSNT) , broadcasting on soil surface (BSNT) under no-tillage paddy condition and conventional machine transplanting(MTT) in Jeonbuk series(siltyloam soil) from 1993 to 1995. Soil hardness was higher in no-tillage soil and increased with highly difference between tillaged and no-tillage soil with deeper soil depth. Bulk density was heavier in no-tillage soil and porosity was higher in tilled soil than that of the control. The rate of effective tiller was higher in MTT, following MTNT, PDSNT, DSNT and BSNT. Weed occurrence was more serious in no-tillage soil, than that of tillaged soil. The rate of lower internode length was lower in DSNT and BSNT and was similar with MTT in PDSNT and MTNT. Height of center gravity in terms of lodging tolerance was lower in direct seeding than in machine transplanting. Depth of buried culm was shorter in no-tillage soil, especially in DSNT and BSNT. Total amount of root was higher in MTT, following MTNT, PDSNT, BSNT and BSNT and the distribution rate of root in shallower soil layer was higher in no-tillage soil, especially in BSNT and DSNT. Field lodging occured highly in BSNT, following DSNA, PDSNT and MTNT with high lodging scale in DSNT and BSNT. Panicle number per unit land square meter was the highest in MTT and the least in BSNT. Ripened grain ratio was low in BSNT and DSNT due to heavy lodging. Yield of milled rice was 93% in PDSNT, 87% in DSNT, 81% in BSNT and 96% in MTNT, compared with 534kg /10a in MTT.