• Korean Journal of Organic Agriculture
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• v.24 no.3
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• pp.557-570
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• 2016

Growth of 6-year old 'Niitaka' pear (Pyrus pyrifolia Nakai) trees and control of insect and disease occurrences were compared between fermented soybean extracts and rain-shelter system for two years. Foliar application of fermented soybean extracts was applied at 6 times as a pre-experiment in the open-field in 2013, with a rain-shelter system in 2014. Fermented soybean extract treatment increased foliar concentrations of approximately 0.46% T-N, 0.17% K, 0.19% Ca, and 0.06% Mg in 2013 compared to the control, with similar macro-nutrients between the control and soybean extract treatment observed in 2014. Rain-shelter system increased foliar concentrations of T-N, Ca, and Mg compared to the open-field. There were no significantly different between the control and soybean extract treatment for number of leaves per fruit, leaf dry weight, phytotoxicity, and completed shoot growth on August during the two years. Rain-shelter system increased leaf dry weight and did not affect phytotoxicity in the leaves. Fruit quality parameters were mostly similar to control and soybean extract treatment for two years, with higher fruit firmness observed for soybean extract treatment. Rain-shelter system advanced 4 days of harvest dates, and increased approximately 7.0 ton fruit yield per ha, 20 g mean fruit weight, and fruit soluble solid contents compared to open-field in 2014. Soybean extract treatment little suppressed occurrence of disease and insect on the leaves and fruits in both years. Rain-shelter system increased occurrence of Venturia nashicola on the leaves and to 63.8% of Gymnosporangium asiaticum on the fruits in 2014. Strong winds and storms in May elevated relative humidity in the rain-shelter system and caused high infection of the disease occurrence, requiring for an additional green control method. Soybean extract treatment little affected tree growth and would have initiated for a long-term study to evaluate tree physiological characteristics. Rain-shelter system improved fruit productivity and advanced harvest dates, which could have been more effective facility at a Thanks Giving Day between middle and end of September.

• Journal of the Korean Society of Radiology
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• v.3 no.2
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• pp.27-31
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• 2009

Now a days, the Medical X-ray equipments has become digitalized from analog type such as film, cassette to CR, DR. And many scientists are still researching and developing the Medical X-ray equipment. In this study, we used the Bismuth tri-iodide to conversion material for digital X-ray equipments and we couldn't get the satisfying result than previous study, but it opened new possibility to cover the disadvantage of a-Se is high voltage aplly and difficultness of make. In this paper, we use $BiI_3$ powder(99.99%) as x-ray conversion material and make films that have thickness of 200um and the film size is $3cm{\times}3cm$. Also, we deposited an ITO(Indium Tin Oxide) electrode as top electrode and bottom electrode using a Magnetron Sputtering System. To evaluate a characteristics of the produced films, an electrical and structural properties are performed. Through a SEM analysis, we confirmed a surface and component part. And to analyze the electrical properties, darkcurrent, sensitivity and SNR(Signal to Noise Ratio) are measured. Darkcurrent is $1.6nA/cm^2$ and sensitivity is $0.629nC/cm^2$ and this study shows that the electrical properties of x-ray conversion material that made by screen printing method are similar to PVD method or better than that. This results suggest that $BiI_3$ is suitable for a replacement of a-Se because of the reduced manufacture processing and improved yield.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.4
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• pp.325-333
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• 1992

An investigation was carried out to find out the effects of long-term application (14 and 28 years) of rice straw, compost and wheat straw on changes in soil chemical and physical properities, aspests of releasing potential nitrogen and nitrogen uptake by rice and maize from fine textured paddy soils with double cropping system in warm temperate area. The result obtained were summarized as follows : 1. The long-term application of organic matters improved plow layer and soil physical properties : bulk density and solid phase were decreased, while porosity and gaseous phase were decreased. 2. Average increment of total carbon per year was 0.0371% and 0.0407% for rice straw and compost, respectively, from 1 through 14 years ; it was 0.0007% and 0.0014% for the rice straw and compost, respectively, from 15 years through 28 years. The average increment of total notrogen per year was 0.0025% and 0.038% for the rice straw and compost, respectively, from 1 through 14 years ; 0.0014% and 0.0024% for the same treatments from 15 through 28 years. 3. $NH_4-N$ and amide-N were high in the soils with wheat straw application for 28 years ; the amino sugar-N in the soils with compost application for 28 years ; amino acid -N in the soils with rice straw application for 14 and 28 years ; and unidentified-N, in the control. 4. The released amount of available nitrogen with the submerged condition was higher at $30^{\circ}C$ than at $25^{\circ}C$ during the incubation. The amount of released available nitrogen at the field was aproximately same as that of $25^{\circ}C$ incubation. However, the released amounts from the incubation and the field were always lower than those extracted with reagents. 5. The amount of nitrogen uptake by rice and maize was highly correlated with available nitrogen extracted with phosphate buffer(pH 7.0). 6. The ratio of yield increase(milled rice) was 17, 12 and 7%, respectively, by application of rice straw, compost and wheat straw for 28 years, and 11% by application of rice straw for 14 years.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.610-613
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• 2012

Oyster shell has a high content of $CaCO_3$ to be used as a acidic soil amendment. To enhance productivity of barley and soil microbe in an upland soil, oyster shell and calcium-magnesium carbonate were selected as a soil amendments in this study. A field experiment was treated no treatment (hereafter, control), oyster shell lime $3.09Mg\;ha^{-1}$ and $2.38Mg\;ha^{-1}$, and calcium-magnesium carbonate $2.38Mg\;ha^{-1}$ as amount of lime requirement in silt loam soil. The yield of barley from the oyster shell lime treatment was the highest. The protein content of barley was the highest of 11.1% in the calcium-magnesium carbonate, followed by 10.7% for the control, 10.6% for the oyster shell lime $3.09Mg\;ha^{-1}$, and 10.4% for the oyster shell lime $2.38Mg\;ha^{-1}$. Soil pH value was higher than that of control in harvesting stage. In addition, the population of soil bacteria was highest in oyster shell lime $2.38Mg\;ha^{-1}$, actinomycetes was highest in calcium-magnesium $2.38Mg\;ha^{-1}$. We concluded that the oyster shell lime can be effective to restore soil nutrient and microbe balance in an upland soil.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.2
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• pp.11-26
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• 1964

The studies reported herein are on the varietal differences of rice in the effects of seeding times and nursery periods on the components such as, culm length, ear length, number of ears, ear weight, straw weight, and grain/straw ratio following the first series of studies on heading date. In the present investigations, 50 rice varieties, as the preceding studies, were seeded nine times at the interval of 15 days from March 15 to July 28 in 1963. Each variety seeded at respective time was transplanted in 40 days in nursery after seeded. Reviewing the result obtained from the first series of the studies on heading date, the number of days required to heading from seeding were decreased by delaying the seeding time. Most varieties tended to decrease in the number of days from seeding to heading by the 8th planting time. Some of varieties seemed to be decreased in the number of days from seeding to heading by 9th seeding time. However most varieties were failed to show heading delaying the seeding date at the 10th seeding. The results on the effects of altering the seeding time on the components and varietal differences of the response are summarized as follows; 1) Culm length; It appeared that culm length was shortened when the number of days from seeding to heading was decreased by delaying the seeding date. The varieties which needed many days to heading were also shortened in their culm length. 2) Ear length; Ear length was also shortened when the number of days needed tocheading was decreased, by delaying the seeding time. The varieties which needed many days for heading were also shortened in their ear length, while those which headed earlier seemed to be lengthened in their ear lengths. 3) Number of ears; It was shown that the number of ears was increased with the delay of the heading date, whereas, at the 9th seeding the number of ears was decreased when delayed the heading date. 4) Ear weight; Ear weight per hill was also likely to be heavy throughout the seeding times and varieties except the 7th and 8th seedings in which it appeared to be light on the contrary. 5) Straw weight; Straw weight became heavier as delayed the seeding date throughout all the varieties and seeding dates. 6) The grain/straw ratio; The grain/straw ratio was gradually increased by the 5th seeding time, reaching the pick at 5th. An examination of the varieties at each seeding date showed that the grain/straw ratio was low from 1st to 3rd seeding and from 7th to 9th seeding, when the number of days required to heading from seeding are increased. At the 4th seeding time-which is standard seeding time-5th, and 6th seeding times the ratio was high with the delay of heading.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.4
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• pp.385-393
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• 2011

Soybean is the most promising crop for substituting rice on the paddy field. Excessive water stress is a common limiting factor in soybean yield under paddy soil condition. This study was carried out to identify changes in leaf total nitrogen and petiole ureide content under excess water conditions for establishing a screening system related to waterlogging tolerance. Waterlogging treatment was conducted by maintaining the water level on the soil surface for 10 days at the early vegetative growth stage ($V_5$) and the flowering stage ($R_2$). Leaf total nitrogen content, SPAD value and ureide content in petiole decreased in all soybean varieties in response to waterlogging, but the degree of decrease was much lesser in Pungsannamulkong and Muhankong than in Jangyeobkong and Myungjunamulkong, at 21 days after waterlogging treatment. This result means that root and nodule recovery rates were much higher in Pungsannamulkong and Muhankong than in Jangyeobkong and Myungjunamulkong after waterlogging treatment. The ureide and leaf nitrogen content showed high positive correlation with SPAD value, regardless of waterlogged stages. In conclusion, leaf nitrogen content, ureide content in petiole and leaf greenness were identified as promising indicator for screening soybeans which are tolerant of excess water.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.1
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• pp.8-17
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• 2018

Pre-harvest sprouting (PHS) refers to seed germination during ripening, due to loss of dormancy before harvest. As PHS in rice causes decrease in grain yield and quality, tolerance to PHS is an important trait of Japonica cultivars in Korea. It is important to investigate the related genes and environmental factors, because PHS is a quantitative trait. In this study, we examined PHS rates at three different times according to the cumulative daily mean temperature after heading (CTAH) for 5 rice cultivars released in Korea for 5 years from 2013 to 2017 to determine the effect of environmental factors on PHS. ABA content in ripening spikelets was analyzed to understand how it was related to PHS tolerance. PHS rate increased as CTAH increased from $800^{\circ}C$ to $1200^{\circ}C$. PHS rate was significantly different (p < 0.001) among the cultivars, showing Dasanbyeo, Jounbyeo, and Nampyeongbyeo to be PHS-tolerant, and Jopyeongbyeo and Gopumbyeo to be susceptible at all the CTAH of 800, 1000, and $1200^{\circ}C$. In 2015 and 2016, PHS rates were relatively higher, because of high temperature and frequent rainfall during the ripening period. In each cultivar, ABA content decreased as CTAH increased from $800^{\circ}C$ to $1200^{\circ}C$. However, there was no significant correlation between ABA content and PHS tolerance among the cultivars.

• Journal of Animal Science and Technology
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• v.55 no.5
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• pp.373-380
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• 2013

The study aimed to develop prediction models of primal cut yield using body measurements of Hanwoo steers in Korea. The progeny of 874 steers at Hanwoo Improvement Main Center from 2008 to 2010 were recorded. Pearson's correlation coefficients for primal cuts and other traits were estimated. Primal cuts were adjusted for slaughter date and age using the SAS GLM procedure. Afterwards, a stepwise regression was performed on each primal cut by fitting body measurement traits. An independent covariable was selected at the highest coefficient of determination with the greater fitness model using Mallows's Cp statistic. Results showed that primal cuts were significantly influenced by slaughter date (P<0.01). The age at slaughter, however, was only significant for the top round (P<0.05). There was a moderate to high correlation between chest girth and tenderloin (0.54), loin (0.74), and rib (0.80). Most primal cut percentages were negatively related to BFT. Similar negative to low positive correlations were observed for primal cut percentage and body size traits. In addition, a correlation of 0.21 was observed between rib percentage and chest girth. The regression of body measurements on the adjusted primal cuts were significant for later traits. Regression estimates revealed that wither height, body length, rump length, hip bone width, and chest girth are important for primal cut weight and percentage determination. In particular, chest girth was always important for primal cut weight estimates.

• The Korean Journal of Pesticide Science
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• v.19 no.4
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• pp.428-439
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• 2015

Pepper anthracnose caused by Collectotrichum acutaum has been known as one of the most damaging diseases of pepper, which has reduced not only yield but also quality of pepper produce almost every year. This study was conducted to develop control strategy against pepper anthracnose by alternate application of agricultural organic materials and chemical fungicides. The alternate application effect of agricultural organic materials and chemical fungicides for controlling pepper anthracnose were examined in vitro and in the field. First, thirteen microbial agents and twenty two agricultural organic materials were screened for antifungal activity against C. acutatum through the dual culture method and bioassay. As a result, one microbial agent (Bacillus subtilis QST-713) and three agricultural organic materials (sulfur, bordeaux mixture, marine algae extracts) were found to show high inhibition effect against C. acutatum. In the field test, when Iminoctadine tris+thiram, a chemical fungicide for controlling pepper anthracnose, was sprayed, it reduced disease incidence by 89.5%. Meanwhile Sulfur, bordeaux mixture, copper, marine algae extracts and Bacillus subtilis QST-713 showed low disease incidence at the range of 33.1~81.0%. However, when Iminoctadine tris+thiram and agricultural organic materials(bordeaux mixture, marine algae extracts) were applied to pepper fruits alternately two times at 7 days interval, there was a 81.7 and 87.1% reduction in disease, respectively. Consequently, the alternate spray of chemical fungicide (Iminoctadine tris+thiram) and agricultural organic materials (bordeaux mixture, marine algae extracts) could be recommended as a control method to reduce the using amount of chemical fungicide.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.4
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• pp.333-338
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• 1999

The experiment was carried out to find the effects of the application method of dairy liquid manure on productivity of silage corn(P3352) and sorghum $\times$ sudangrass hybrid(P988) and physical and chemical properties of soil during 2 years at Suwon. Crude protein content of T1(Chemical fertilizer) was highest by 6.5%, 8.9% in both forage, respectively, but total digestible nutrient(TDN) percent of T3(dairy liquid manure, basal + chemical fertilizer, topdressing) was highest by 73.8%, 59.0% in both forage, respectively. In TND yield, it was little different between T1(9.5 MT/ha) and others(8.4~9.3 MT/ha) at silage corn, but T4(chemical fertilizer at basal + dairy liquid manure at topdressing) was highest as 13.3 MT/ha at sorghum $\times$ sudangrass hybrid(p<0.05). pH of the soil after experiment was lower than that of the soil before experiment in the both forages, but soil organic matter was high at after trial than before trial. Available phosphorous and exchangeable cation were not shown the regular trend in this experiment. Based on the results of this experiment, it was not shown among different application method for silage corn (P3352), but application of chemical fertilizer at basal and liquid manure at topdressing was good for sorghum $\times$ sudangrass hybrid(P988).