• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.98-105
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• 1989

The examination to find out how the activity of glutamine synthetase (GSA) develop in each wheat leaves during the growth period was carried out. GSA/g FW/leaf were very low at leaf differentiation stage and increased highly several times by unfolding and development of leaf, and declined deeply with the advance of senescence in each leaves. GSA/g FW/leaf were risen gradually from the every lower leaves to the every upper leaves, in consequence activity level and maximum peak per g fresh weight of 7th-flag leaves were two or three times higher than those at the 1st-4th leaves in all of 12 applied nitrogen treatments, thereupon. the highest activities per g fresh weight showed in the 8th leaves. GSA/g FW/leaf was shown two peaks in the 6th-flag leaves and one peak in 1st-4th leaves, respectively. GSA/g FW/leaf (except for senescence leaves) and GSA/plant were increased gradually to the infloresscence emerging stage and were shown the first maximum peak at 13 days before anthesis, then were declined rapidly. to the milk ripe stage (7 days after anthesis). and were shown the second maximum peak at the early dough ripe stage (22 days after anthesis) .

• Economic and Environmental Geology
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• v.6 no.2
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• pp.115-122
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• 1973

The writer intended to observe the relative mobility of elements in weathering process of granite, on the outskirts of IRI city at Jeollabukdo KOREA. He analysed fresh granites and weathered ones of Hwang-Dung granite mass and had following conclusions by the triangular diagrams and the oxidized variation diagrams of the analysis. 1) The increasing phenomena of $H_2O$ observed clearly in early and late stage of weathering processes. 2) Granites was weathered by physical weathering in early stage, and it was weathered by chemical weathering in late stage. 3) The ratio of $FeO/Fe_2O_3$, FeO/MgO, and $SiO_2/Al_2O_3$ decreased uniformly from early to late stage of weathering processes. 4) It was proved that weathering potential of granite was larger than that of basaltic rock. 5) The order of mobility in major elements was Ca, Na, K>Si>Mg>Fe, Al.

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.08a
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• pp.124-125
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• 2005

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.3
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• pp.145-149
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• 1988

The effects of temperatures, salinities and diets on the larvae of the fresh water prawn, Macrobrchium koreana were studied. Survival rates were decreased with increasing salinity concentrations, and the second larval stages were almost died in 48 hours in over $40\%$ sea weter$(13.7\%)$. The intermolt duration of the each stage were shortend with increasing water temperature, and the optimum temperatures of the larvae were from $22^{\circ}C\~26^{\circ}C$ The larvae fed with the meat of Tapes japonicus showed the highest survival rate. When the larvae were fed with the eggyolk powder, all the lauvae died before fourth zoea. Under starved condition moltings were continued up to third zoea.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.4
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• pp.237-244
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• 2013

Radar remote sensing is appropriate for monitoring rice because the areas where this crop is cultivated are often cloudy and rainy. Especially, Synthetic Aperture Radar (SAR) can acquire remote sensing information with a high temporal resolution in tropical and subtropical regions due to its all-weather capability. This paper analyzes the relationships between backscattering coefficients of rice measured by RADARSAT-2 SAR and growth parameters during a rice growth period. We examined the temporal variations of backscattering coefficients with full polarization. Backscattering coefficients for all polarizations increased until Day Of Year (DOY 222) and then decreased along with Leaf Area Index (LAI), fresh weight, and Vegetation Water Content (VWC). Vertical transmit and Vertical receive polarization (VV)-polarization backscattering coefficients were higher than Horizontal transmit and Horizontal receive polarization (HH)-polarization backscattering coefficients in early rice growth stage and HH-polarization backscattering coefficients were higher than VV-polarization backscattering coefficients after effective tillering stage (DOY 186). Correlation analysis between backscattering coefficients and rice growth parameters revealed that HH-polarization was highly correlated with LAI, fresh weight, and VWC. Based on the observed relationships between backscattering coefficients and variables of cultivation, prediction equations were developed using the HH-polarization backscattering coefficients.

• Horticultural Science & Technology
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• v.35 no.1
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• pp.88-97
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• 2017

This study explored the physicochemical and nutritional changes associated with storage duration of fresh tomatoes. Fruits of the 'TY Megaton' and 'Yureka' tomato cultivars were harvested at the pink stage and stored at $12^{\circ}C$ for 20 days. During storage, firmness, weight loss, skin color (Hunter L, a, b, a / b values), soluble solids content (SSC), titratable acidity (TA), pH, antioxidant contents (lycopene, ascorbic acid, and total phenolics) and antioxidant activity were evaluated. Firmness was above the minimum marketable limit and fresh weight loss was below maximum acceptable weight loss after 3 weeks of storage, and no deleterious effect on antioxidant contents or activities were observed. Significant differences in SSC, TA, and pH were seen between varieties, but not between fruits stored for different durations. In both varieties, Hunter a values increased more than five-fold after 8 days of storage; this correlated with a more than four-fold accumulation of lycopene after two weeks of storage. The antioxidant activity of tomatoes was highest at the beginning of the storage period, likely because of the effective DPPH - reducing power of ascorbic acid and total phenolics. Antioxidant activity increased after 12 days of storage because of increasing lycopene content. Hence, this study indicates that pink - stage tomatoes may be stored at $12^{\circ}C$ for up to 3 weeks without affecting marketability or nutritional value.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.3
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• pp.190-194
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• 1993

This experiment was conducted to investigate the effects of concentrated sulfate on the germination rate, growth rate and the productivity of weight of kudzu (Pueraria thwnbergiana Bentham). The germination rate of kudzu seed by one or two treatment retreatment with the concentrated sulfate for minutes of 5. 10, 15 and 20 were determined respectively. The results obtained were summarized as follows; 1. In the time of concentrated sulfate treatment, the germination rate was the highest in the once treatment for 20 minute. and the retreatment was higher than the once treatment in the germination rate. 2. The changes of plant length by growth stage was grown gradually until for 60 day and rapidly after for 60 day. The growth rate was the highest in treatment for 15 minute than in other treatments. 3. The stem diameter. stem weight. fresh weight and root weight by the treatment with sulfate 15 minute as the treatment with once were high degree of productivity. 4. The number of branch. number of nodes and root weight by the growth stage were higher growth rate before for 90 day than after for 90 day, however stem weight and fresh weight were high degree of productivity after for 60 day.

• Korean Journal of Medicinal Crop Science
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• v.12 no.3
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• pp.231-236
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• 2004

Crop productivity would be determined by relative capacity of source and sink. The study was carried out to measure the effects of shading and flower bud pinching on growth and yield of Atractylodes japonica Koidz. Shading treatment after transplanting was done at 100%, 65, 45 or 25% level of natural light intensity but the pinching treatment was to remove all the inflorescences formed after June 10, July 10, August 10 or none. Growth and yield at early and late stages were periodically measured. At the early stage, shading mainly influenced fresh weight rather than morphological characters. At the late stage, however, severer shading decreased numbers of stems, leaves, roots, fraction and total fresh weight. 65% shading from July 1 to September 30 after skipped the emerging and early growth stages showed nearly same growth and morphological characters but more rhizome yield per unit area than non-shading. In flower bud pinching treatment, earlier pinching increased number of roots, fraction fresh weights per plant and rhizome yield per unit area.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.5
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• pp.431-436
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• 1994

The objective of experiment was to investigate the effects of sowing dates on forage yield and growth characteristics of rye in paddy field cultivation in midwest region of Korea. The field experiment treated with 5 levels of sowing dates was carried out at Yesan from october 1990 to june 1991. The field emergence rate and winter survival rate were decreased with delay in sowing dates by the days from sowing to emergence were took a long period of time. The crop growth rate were increased with early in sowing date. The fresh and dry weight of rye were increased with early in sowing date, but there was no significant differences between sowing date from Oct. 5 to Oct. 25. The highest fresh yield was obtained at flowering stage and the highest dry yield was obtained at milky stage. The ratio of leaf blade and leaf sheath in rye plant were decreased with earlier sowing date and delayed harvest, but the ratio of stem and inflorescence was vice versa.

• Journal of Crop Science and Biotechnology
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• v.10 no.1
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• pp.33-38
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• 2007

Nitrogen management at the panicle initiation stage(PI) should be fine-tuned for securing a concurrent high yield and high quality rice production. For calibration and testing of the recommendation models of N topdressing rates at PI for target grain yield and protein content of rice, three split-split-plot design experiments including five rice cultivars and various N rates were conducted at the experimental farm of Seoul National University, Korea from 2003 to 2005. Data from the first two years of experiments were used to calibrate models to predict grain yield and milled-rice protein content using shoot fresh weight(FW), chlorophyll meter value(SPAD), and the N topdressing rate(Npi) at PI by stepwise multiple regression. The calibrated models explained 85 and 87% of the variation in grain yield and protein content, respectively. The calibrated models were used to recommend Npi for the target protein content of 6.8%, with FW and SPAD measured for each plot in 2005. The recommended N rate treatment was characterized by an average protein content of 6.74%(similar to the target protein content), reduced the coefficient of variation in protein content to 2.5%(compared to 4.6% of the fixed rate treatment), and increased grain yield. In the recommended N rate treatments for the target protein content of 6.8%, grain yield was highly dependent on FW and SPAD at PI. In conclusion, the models for N topdressing rate recommendation at PI were successful under present experimental conditions. However, additional testing under more variable environmental conditions should be performed before universal application of such models.