• Korean Journal of Weed Science
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• v.6 no.2
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• pp.102-109
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• 1986

To know the ecological pattern of bulrush (Scirpus juncoides) seeds in dormancy-breaking responses as affected by different ripening processes, storage conditions, germination conditions, and some of known chemicals concerned, the study was conducted. Among other conditions detected, the burial in 2 cm depth paddy soil, $5^{\circ}C$ storage temperature, pre-maturing process (Green color), high concentration of chemicals used, and flooding paddy surfaces were the most efficient conditions for bulrush seeds to break dormancy and germinate, respectively.

• Korean Journal of Weed Science
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• v.15 no.3
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• pp.175-182
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• 1995

The experiment was conducted to obtain basic information on weed ecology and effective weed control in direct-seeded rice Gelds at National Yeongnam Agricultural Experiment Station in 1994. Double cropping system of rice-barley reduced weed occurrence about 30% as compared with rice single cropping due to allelopathic effect of barley residue or stubble. Occurrences of red rice (weedy rice), barnyard grass and water foxtail were closely related with tillage method; the greatest occurred in no tillage plot followed by rotavation only and plow plus rotavation. Period of seed germination of barnyard grass and carbgrass varied with temperature and soil depth. In the same environmental condition, the germination period of barnyard grass shortened 3 to 5 days as compared with that of carbgrass. Two systematic applications of herbicides, that is, the first application at 10 to 15 days after seeding and the second at just after flooding, were the most recommendable system in dry-seeded rice field in terms of weed suppression and yield capacity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1136-1142
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• 2005

To develop new anti-aging foods or cosmetics by using antioxidants, SOD activator and elastase inhibitor, both potent anti-aging substances, were screened from various extracts of medicinal Plants and its optimal extraction conditions were investigated. Antioxidant activity has showed the highest in methanol extracts of Prunus persica (seed; 98.0$\%$). Methanol extracts of Morus alba (leave; 41.0$\%$) showed the highest elastase inhibitory activity while Lycium chinense (fruit; 197$\%$) showed the highest activation effect in SOD activity. The Prunus persica extract that exhibited the highest activity was extracted by treatment of Prunus persica powder with methanol at 40$^{\circ}C$ for 18 h and the SOD activity was maximum with extract from Lycium chinense extracted with deionized water at 30$^{\circ}C$ for 12 h. Elastase inhibitory activity of Morus alba was maximally extracted when it was treated with 70$\%$ methanol at 50$^{\circ}C$ for 12 h.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.393-400
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• 2015

An insect parasitic mite was found on a larva from Japanese apricot seed. The mite was identified as Pyemotes moseri Yu et Liang (Acarina: Pyemotidae) new to Korea. The host larva was identified as Eurytoma maslovskii using mitochondrial DNA sequencing analysis. We conducted preliminary study on its reproduction and parasitization capacity in laboratory condition. A mated female mite reared on Eurytoma maslovskii larva. We counted and sexed newborn progenies and then eliminated them during periodical observations. To test parasitization capacity, a PCR tube containing mass reared P. moseri and Japanese apricot seeds (assumed bear larva of E. maslovskii) placed in a stainless bath filled with potting soil. One month later, we surveyed the seeds whether the E. maslovskii larva parasitized by mite or not. We repeated this experiment three times with five replications each. Average life span (days from parasitization to the end of reproduction) of gravid females was 24.4 days (n=8). A gravid female reproduced 104.0 female progenies (n=8). Although there were more than seven Japanese apricot seeds per bath containing larva or pupa, we found parasitization only in two seeds.

• The Korean Journal of Malacology
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• v.28 no.1
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• pp.21-28
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• 2012

The combined effects of water temperature and salinity on the settlement rate and density (spats/$cm^2$) of Crassostrea gigas pediveliger larvae were studied under the hatchery conditions. Four water temperatures (20.0, 23.0, 26.0 and $29.0^{\circ}C$) were tested at three salinities (20.0, 30.0 and 40.0). The optimum water temperature by salinity conditions were $29.0^{\circ}C$ and 20.0, 30.0 which significantly (P < 0.05) the highest mean (${\pm}S.D$) larval settlement rate of $43.1{\pm}0.1%$, $42.1{\pm}0.1%$, respectively. But the combination of water temperatures and salinities for settlement density was not effected, but each factor as water temperature ($29.0^{\circ}C$), salinity (40.0) was shown significantly high and low settlement density, respectively (P < 0.05). The statistics result of settlement density frequency was appeared: mode ($1.2-2.3spats/cm^2$), Mean ($1.9-2.4spats/cm^2$), Range ($3.0-5.8spats/cm^2$) and the lowest variance was obtained 0.4 at water temperature $20.0^{\circ}C$ by salinity 30.0, but $29.0^{\circ}C$ by 20.0 was the highest (1.1). The best condition at this results for the larvae setting under the artificial seed collection of C. gigas was $29.0^{\circ}C$ and 20.0-30.0.

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.51-59
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• 2014

In this study, we developed a high frequency watermelon regeneration system using three breeding lines ('B02', 'B05' and 'D04') of watermelon (Citrullus lanatus (thunb.) Matsum. & Nakai) which are differed in their fruits in shape, color of pericarp and flesh. The highest frequency of explants with callus was observed by using explants that consist of cotyledon proximal part end in all breeding lines, and the highest rate of callus induction was obtained on MS medium containing 1.0 mg/L BAP + 0.5 mg/L IAA for 'B02' (94%), 3.0 mg/L BAP for 'B05' (95%), 3.0 mg/L BAP + 0.1 mg/L IAA for 'D04' (90%). The highest shoot regeneration rates from derived callus were obtained on MS medium containing 1.0 mg/L BAP + 0.5 mg/L IAA for 'B05' (94%), and then a 'B02' (81%) with a same culture conditions, and the lowest regeneration was obtained on MS medium containing 1.0 mg/L BAP for 'D04' (56%). Regenerated plants showed the best rates of root formation on MS containing 0.1 mg/L IBA for 'B02' (67%), 0.1 mg/L NAA for 'B05' (87%), 0.5 mg/L IAA for 'D04' (88%). The regenerated plants showed a 100% survival rate in soil condition. The tissue culture and regeneration conditions obtained from this study will be useful for regenerating plants in breeding applications, and will be a useful tool for further genetic transformation studies on watermelons.

• Molecules and Cells
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• v.40 no.3
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• pp.230-242
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• 2017

In the Arabidopsis genome, approximately 80 MAP3Ks (mitogen-activated protein kinase kinase kinases) have been identified. However, only a few of them have been characterized, and the functions of most MAP3Ks are largely unknown. In this paper, we report the function of MAP3K16 and several other MAP3Ks, MAP3K14/15/17/18, whose expression is salt-inducible. We prepared MAP3K16 overexpression (OX) lines and analyzed their phenotypes. The result showed that the transgenic plants were ABA-insensitive during seed germination and cotyledon greening stage but their root growth was ABA-hypersensitive. The OX lines were more susceptible to water-deficit condition at later growth stage in soil. A MAP3K16 knockout (KO) line, on the other hand, exhibited opposite phenotypes. In similar transgenic analyses, we found that MAP3K14/15/17/18 OX and KO lines displayed similar phenotypes to those of MA3K16, suggesting the functional redundancy among them. MAP3K16 possesses in vitro kinase activity, and we carried out two-hybrid analyses to identify MAP3K16 substrates. Our results indicate that MAP3K16 interacts with MKK3 and the negative regulator of ABA response, ABR1, in yeast. Furthermore, MAP3K16 recombinant protein could phosphorylate MKK3 and ABR1, suggesting that they might be MAP3K16 substrates. Collectively, our results demonstrate that MAP3K16 and MAP3K14/15/17/18 are involved in ABA response, playing negative or positive roles depending on developmental stage and that MAP3K16 may function via MKK3 and ABR1.

• Korean Journal of Medicinal Crop Science
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• v.5 no.2
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• pp.162-166
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• 1997

Variations in growth and yield of adlay(Coix lachyma-jobi var. ma-yuen Stapf) was monitored in farmer's fields in Yunchon, the main producing area in Korea, where the field condition showed difference in topograyphy, crop rotation, and ridge shape. Rotation cropping increased remankably stem length, and number of effective tillers, reduced the occurrence of leaf blight and crop damage by the disease, and in addition showed positive effect to repress the occurrence of stem-borerin upland field. Stem length was greater in upland field than in paddy field and this result seemed to be related to lodging degree. The even field with crop rotation system showed the highest seed yield and followed by hillside field and paddy field resulted the lowest yield.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.2
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• pp.38-48
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• 1980

To evaluate Rhizobium meliloti BALSAC, a strain selected from Canada as an acid tolerant one, and ordinary lucerne inoculant in acid condition, lucerne (Medicago sativa L. cv. Wairau) was inoculated and/or pelleted in the laboratory, and grown for two months in an acid soil (Lismore silt loam, pH 5.4) with three levels of lime in the, glasshouse. The results of controlled (noninoculated), nitrogen fertilized, laboratorial and commercial inoculated seeds were compared to give the following conclusions: 1. There was no significant difference in the top and root dry matter yields between two Rhizobium strains. However, Balsac inoculant showed higher single nodule dry matter weight and relatively higher number of larger nodules than the ordinary inoculant. 2. Lime application increased dry matter yields of plants and nodules, and the number of nodules per pot and the increase of nodules on the lateral roots in both inoculants. Lime application also caused an evenly distribution of nodules on the root by showing an increase of nodules mainly on the lateral roots. 3. Fertilizer nitrogen without inoculant slightly increased the nodulation percentage, the nodule dry matter weight per nodule and the relative proportion of larger nodules. 4. Commercially inoculated and pelleted seed showed less consistent results. 5. Relatively larger variations in measuring nodule characteristics was discussed and concluded that extreme cares should be given to reduce the variation.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.1
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• pp.42-48
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• 2012

In this study, experiment on phosphorus removal was performed by using microbubble liquid film flotation tank with microbubble module. After dissolving gas and liquid in dissolving tank, microbubble liquid film system created microbubbles in equal size under fixed low pressure. After being passed through $A_2O$ and m-$O_3$ process, secondary treatment wastewater was used as influent in phosphorus removal process. When the T-P concentration of influent was 2.89 mg/L, alum(8%, 30 mg/L) was injected into a microbubble flotation tank, the treatment resulted 94% of T-P removal rate. Remaining T-P concentration was less than 0.2 mg/L, which is in accord with the effluent quality standard. Seasonal variations in water temperature showed no differences in T-P removal property. When the inflow concentration of SS was 1.0 mg/L or more, it served as coagulation nuclei in the coagulation process. In that condition, average T-P removal rate was higher than 97%. When 50% of floated scum was returned, coagulator Al included in scum assisted the injected coagulator and maximized the coagulation efficiency of pollutant. In such treatment, the T-P concentration was measured as 0.18 mg/L and satisfied the outflow water quality standard, which is 0.2 mg/L or less.