• Korean Journal of Agricultural Science
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• v.5 no.2
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• pp.43-48
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• 1978

To information on the inheriance of heading date of rice under the short-day condition, the $F_2$ seeds obtained from all possible combinations of the diallel crosses between five leading rice varieties: Nongbaek, Tongil, Palgueng, Mangyeong and Gimmaze were grown under the short-day condition and natural condition. The days to heading were investigated and analysed for genetic components. The results obtained are summarized as follows. 1. Under the natural condition, the durations to heading of all combinations excluding Nong-baek x Palgueng and Nongbaek x Mangyeong were longer than those of their parents. mean. Whereas, under the short-day condition, the duration to heading of Mangyeong x Gimmaze combination was equal to that of their parents mean, and those of all other combinations were significantly shorter than those of their parents mean. 2. Under the natural condition, the non-allelic gene interactions were significant in days to heading, but under the short-day condition, the non-allelic gene interactions were not significant, and inheritance of days to heading revealed partial dominace in which additive effects were greater than dominant effects. 3. Tongil and Gimmaze were located on dominant zone under the natural day-length, and Nongbaek and Mangyeong were under the short-day condition. 4. Under the natual condition, dominant effects were greater than additive effects, and both heritabilities of the broad and the narrow senses were significantly low. Under the short-day condition, additive effects were significantly higher than dominant effects, and both heritabilities of the broad and the narrow senses were high.

• Journal of Bio-Environment Control
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• v.19 no.1
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• pp.49-54
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• 2010

The study was conducted to compare the postharvest physiology and storability of fresh cut paprika fruits classified by normal, blossom end rot(BER), and misshapen (or knots) fruit. Some disordered paprika fruits that were produced frequently during high temperature season in highland, were sorted out to non-marketable products. These fruits are mostly wasted, but some of them may be used for fresh cut. The respiration rate of fresh cut paprika fruits was lower and ethylene production rate was higher in normal fruits than in disordered fruits, but there was no significant difference. The fresh-cut paprika fruits were stored in MAP conditions at $4^{\circ}C$, $9^{\circ}C$ and room temperature in 25 ${\mu}m$ and 50 ${\mu}m$ thickness ceramic film packaging. The fresh weight of fresh cut paprika fruits decreased below to 1.1% regardless of fruit types, but the fresh weight loss increased in thinner packaging materials and lower storage temperatures. There were not significant different carbon dioxide and oxygen contents in MAP of all fruit types, while $4^{\circ}C$ storage temperature treatment and 25 ${\mu}m$ thickness ceramic film treatment had lower carbon dioxide and higher oxygen contents. Moreover, the carbon dioxide and oxygen contents were changed rapidly at 9 days in $4^{\circ}C$ storage and at 6 days in $9^{\circ}C$ storage when the visual quality of fresh cut decreased dramatically. The ethylene concentration of packages was below 7 ${\mu}l{\cdot}l^{-1}$ in all treatments during storage, while the treatments of thinner packaging material and lower storage temperature showed lower ethylene concentration. The fresh cut of disordered fruits showed less visual quality than normal fruit treatment in both $4^{\circ}C$ and $9^{\circ}C$ storage temperatures, but there was no significant difference. The value of $4^{\circ}C$ treatment that measured 12 days in storage was higher than $9^{\circ}C$ treatment that measured 9 days in storage. The results suggest that the disordered fruits may be used to fresh cut product without any concerns that they will decreased the value of commodities more quickly than the fresh cut made of marketable paprika fruits. As the fresh cut paprika fruits stored in MAP condition, the more effective storage temperature is $4^{\circ}C$ that may have induced chilling injury a whole fruit of the paprika.

• Korean Journal of Organic Agriculture
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• v.22 no.1
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• pp.97-113
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• 2014

An actual proof experiment was carried out to establish the production of high quality organic rice at farm household in Gwangjin, Junnam, Korea 2011. Experimental plot was designed with conventional organic cultivation and manual organic cultivation in both Hopeongbyeo and Onnuri varities. Experimental field was consisted with suitable drainage loam soil, anryong series, and normal paddy field. Chemical characteristics of the soil were investigated from initial soil and soil after harvest in experimental sites. Seed disinfection was treated with hot water dipping method at $60^{\circ}C$ for 10 min. Rice transplanting was carried out at 17 June with 25 days seedling using machine transplanting. Golden apple snail was used to prevent weed growth as middle size (1.5~1.7 kg/10a) at one week after rice transplanting. Amount of applied fertilizer in experimental plot was supplied with organic fertilizer for the shortage after harvest of hairy vetch (1,100 kg/10a). Bordeaux mixture was used to control of sheath blight and neck blast disease in all experimental plot at 19 Aug. Application of chitin culture solution was treated in manual organic cultivation at 2 and 15 Aug. At late growth stage, incidence rate of neck blast was the highest level at Hopyeongbyeo in conventional organic cultivation. Incidence rate of sheath blight in both Hopyeongbyeo and Onnuri was higher in conventional organic cultivation than in manual organic cultivation. Incidence of rice leaf folder was the highest level at Onnuri in conventional organic cultivation. Yield index in manual organic cultivation was increased by 13% and 38% at Onnuri and Hopyeongbyeo, respectively, compared with conventional organic cultivation. Head rice percentage in both Hopyeongbyeo and Onnuri was slightly increased in manual organic cultivation. These results indicate that high quality production of rice organic cultivation could be depending on management of safe fertilization with nutrient content in soil.

• Asian Journal of Turfgrass Science
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• v.23 no.1
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• pp.133-142
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• 2009

This study was initiated to evaluate the K leaching potential in the green soils and K uptake by the turfgrass in the golf course using the K fertilizers. The turfgrass, Floradwarf bermudagrass(Cynodon dactylon L. $P_{ERS}$.) was planted and grown in the mixture of sand and peat moss in this lysimeter study. Eight representative K fertilizers, such as, monopotassium phosphate (MKP), KCL, $K_2SO_4$, $KNO_3$, CKCl, $CK_2SO_4$, $CKNO_3$, and 0-20-20(liquid) were used in this study. Based on the total K quantity of leachate collected during the whole 12 weeks, 0-20-20 is the K fertilizers the most contributing to the leaching of K, then MKP, the second, KCL, the third, and finally $KNO_3$ are K fertilizers contributing to the K leaching. However, most amount of K applied and collected in the lysimeter were leached during the first period of two and four weeks, compared to that of K leached during the second period of six, eight, ten, and twelve weeks. Application of CKCL and $CK_2SO_4$ producted the largest amount of total dry matter, then MKP and KCL, $KNO_3$ and $CKNO_3$, 0-20-20 in second group. However, except $K_2SO_4$, most K fertilizer sources such as MKP, KCL, $KNO_3$, CKCL, $CK_2SO_4$, $CKNO_3$, 0-20-20 showed the largest amount of K uptake, except $K_2SO_4$. Therefore, based on the K leaching, dry matter production, and plant K uptake, it appears that the coated fertilizers, CKCL, $CKNO_3$, and $CK_2SO_4$ are the environmentally sound fertilizers recommended in the turfgrass green soil of golf course.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.1
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• pp.83-89
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• 1990

A sweet corn hybrid, Golden Cross Bantam 70, was grown at 0, 5, 10, 15 and 20kg/10a of nitrogen (N) under the transparent P. E. film mulch to find the best yield evaluation method. Culm length, ear height, number of tillers increased and silking date was earlier by 1-2 days with increased N level. Leaf area index of main culm at harvest increased with increased N level. Marketable ears were divided into two classes according to the whole sale market price; the frist grade of which husked ear weight over 150g (unhusked ear weight 230g) and the second grade of which husked ear weight between 100 and 150g (unhusked ear weight between 180 and 230g). Average length, thickness, and weight of both grades of marketable ears were not different among the N levels. The proportion of the first grade increased with increased N level. However, total number and weight of marketable ears and gross income per 10a calculated considering weight and number of ears increased with increased N level. There were highly positive correlations between gross income and ear number or ear weight per l0a. The number and weight of marketable ears were underestimated at high N levels compared with gross income. Dry matter yield of stover ranged 740-963kg/10a and increased with increased N level with 20. 8-24.5% dry matter content. Rice black-streaked dwarf virus infection rate was 11.8-15.0%, but it was not related to N level. N concentration in ear was similar but that in stover increased with increased N level. Total N uptake increased but N recovery decreased with increased N level.

• Journal of Bio-Environment Control
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• v.22 no.2
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• pp.87-90
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• 2013

The average annual and winter ambient air temperatures in Korea have risen by $0.7^{\circ}C$ and $1.4^{\circ}C$, respectively, during the last 30 years. Due to climate change, the occurrence of abnormal weather conditions has become more frequent, causing damage to vegetable crops grown in Korea. Hot pepper, chinese cabbage and radish, the three most popular vegetables in Korea, are produced more in the field than in the greenhouse. It has been a trend that the time for field transplanting of seedlings is getting earlier and earlier as the spring temperatures keep rising. Seedlings transplanted too early in the spring take a longer time to resume the normal growth, because they are exposed to suboptimal temperature conditions. This experiment was carried out to figure out the change of cellular tissue of chinese cabbage under the condition of low temperature to provide the information regarding the coming climatic change, on the performance of 'Chunkwang' chinese cabbage during the spring growing season. In our study, plant height, number of leaf, chlorophyll and leaf area was lower at the open field cultivation than heating house treatment after transplanting 50 days. Especially in fresh weight, compared with heating treatment, open field and not heated treatment were notably low with the 1/3 level. Of damage symptoms due to low temperature cabbage leaves about 10 sheets when $-3.0^{\circ}C$ conditions in chinese cabbage was a little bit of water soaking symptoms on the leaves. $-7.4^{\circ}C$ under increasingly severe water soaking symptoms of leaf turns yellow was dry. Microscopy results showed symptoms of $-3.0^{\circ}C$ when the mesophyll cell of palisade tissue and spongy tissue collapse, $-7.4^{\circ}C$ palisade tissue and spongy tissue was completely collapsed. The result of this study suggests that the growers should be cautioned not to transplant their chinese cabbage seedlings too early into the field, and should be re-transplanting or transplanting other plants if chinese cabbage are exposed to suboptimal temperature conditions ($-3.0^{\circ}C$ or $-7.4^{\circ}C$).

• The Journal of Society for e-Business Studies
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• v.8 no.2
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• pp.99-111
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• 2003

By virtue of diverse advantages derived from digital media, eBook is getting started to use. And many market research agencies have predicted that its market will be greatly expanded soon. But against those expectations, copyright-related problems and the difficulties of its accessing inherited from various eBook content formats become an obstacle to its diffusion. The first problems can be solved by DRM technology. And to solve the second problems, each nation has published its own content standard format. But the domestic standards are useful only the domestic level, they still leave the problems in the national level. The variety of content formats has created a demand for mechanisms that allow the exchange of eBook contents. Therefore we study the mapping relations between eBook contents for conversion. To define the mapping relations, first we extract the mapping both between eBook contents and between normal XML documents. From those mappings, we define seven mapping relations and classify them by cardinality. And we analyze the classified relations, which can be generated by automatic, or not. Using these results, we also classify the eBook content conversion as automatic, semi-automatic, and manual. Besides, we provide the conversion templates for mapping relations for automatic generation of conversion scripts. To show the feasibility of conversion templates, we apply them to the eBook content conversion. Experiment shows that our conversion templates generate the conversion scripts properly. We expected that defined mapping relations and conversion templates can be used not only in eBook content conversion , but also in normal XML document conversion.

• The Korean Journal of Pesticide Science
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• v.16 no.2
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• pp.171-177
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• 2012

Pepper seedlings of 6-leaf stage were inoculated with cell suspension of Xanthomonas euvesicatoria 1523 7 days after the application of Bion-M by soil-drenching. Disease severity in the treatment with 20 ${\mu}g\;mL^{-1}$ of acibenzolar-S-methyl, with which Bion-M was composed, was 19%, whereas that of the untreated control was 75%. The resulting control value of acibenzolar-S-methyl was calaulated as much as 74.7%. The control value of acibenzolar-S-methyl was dependent with the applied concentrations and ranged 29.3% to 49.3% at 4.0 and 0.8 ${\mu}g\;mL^{-1}$ of acibenzolar-S-methyl, respectively. Phytotoxicity was observed at 20.0 ${\mu}g\;mL^{-1}$, as lower leaves became to be yellowed and defoliated. The cell density of inoculum suspension of X. euvesicatoria 1523 affected the control value of acibenzolar-S-methyl. With optical density (O.D.) of 0.5 the control value of 4.0 ${\mu}g\;mL^{-1}$ of acibenzolar-S-methyl was 86.0%. However, the control value improved as high as 97.8% at the O.D. value of 0.1. The control value was 75.0% in adult plant of pepper, when acibenzolar-S-methyl was treated by soil-drenching 7 days before inoculation with cell suspension of X. euvesicatoria 1523. The control effect of acibenzolar-S-methyl on pepper bacterial spot was obtained in pepper field, showing that the control value at 10.0 ${\mu}g\;mL^{-1}$ was 71.2%.

• Journal of Plant Biotechnology
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• v.42 no.1
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• pp.43-48
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• 2015

It is a serious situation that the farmers' income has gradually decreased due to the decline of productivity of fruit trees infected with viroids. It has been known that Persimmon viroid (PVd) and Citrus viroid (CVd) are economically important viroids that can infected persimmon. In this study, the incidence of CVd and PVd in 'Fuyu' persimmon were identified as 41% and 34% in JeollaNam-do, respectively. The collected persimmon samples infected by both PVd and CVd were used for testing efficiency of the viroid inactivation methods. The samples were subjected to single treatment of the heat treatment ($37^{\circ}C$), cold treatment ($4^{\circ}C$), or antiviral agent treatment (Ribavirin), and double treatment of combinations of the three methods. Viroid inactivation efficiency was confirmed through RT-PCR. In the case of the samples subjected to cold treatment for 4 weeks, the viroid inactivation efficiency was most significantly high as 67% against the survival rate of 100%. In addition, in the case of the samples treated for 2 weeks with the antiviral agents and cold treatment, the viroid inactivation rate was similar to that of the cold treatment. In conclusion, the cold treatment showed the highest viroid inactivation efficiency, and this result will provide valuable information for production of viroid-free persimmon.

• Korean Journal of Weed Science
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• v.1 no.1
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• pp.57-68
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• 1981

To clarify the mode of uptake of butachlor (2-chloro-2', 6'-diethyl-N-(butoxymethyl) acetanilide) by rice seedlings, its phytotoxic action to growth and physiological activities, studies were conducted with rice seedlings, at the 6th or 7th leaf-stage, which were treated with nutrient solution containing butachlor 0, 1.8, 3.6, 7.2, 10.8 or 14.4 ppm for 1, 2 or 4 days, in other case, the solutions were thereafter renewed with the untreated nutrient solution for further growth. Uptake of butachlor by rice seedlings increased linearly with increase of its concentration and duration of uptake. Butachlor inhibited root growth more than shoot growth, furthermore, the inhibitory effect on the shoot growth was greater in height than in weight or leafing rate. After 4 day-treatment, the rates of shoot growth in weight were delayed for 4 days. Butachlor inhibited water uptake rapidly and linearly with increase of its external concentration. The reduced uptake of water was followed by slow increase in the stomatal resistance of leaves. Upon completion of butachlor treatment, rate of water uptake was recovered rapidly, but the stomatal resistance with lag in time. Butachlor did not affect the uptake of cation such as ammonium, potassium and calcium, but inhibited substantially uptake of nitrate in proportion to its concentration. Especially, butachlor did not affect synthesis and degradation of nitrate reductase. In addition, butachlor has shown much greater binding to the lipidic substances from rice roots than the proteinous material. The primary mechanism of phytotoxic action of butachlor does not seem to be its effect on the protein synthesis, but great affinity to membranes. The inhibition of water uptake, and its subsequent closure of stomates is thought very important for reduced growth under mild phytotoxicity.