• Horticultural Science & Technology
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• v.31 no.1
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• pp.8-13
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• 2013

This research was conducted to investigate the effect of climatic factors on fruit growth in 'Niitaka' pear (Pyrus pyrifolia). For ten years from 2000 to 2010, average full bloom date was April 19th and standard deviation was 4.2 days. Average fruit diameter 160 days after full bloom (DAFB) was 102.4 mm and standard deviation was 7.5 mm. Variance coefficients among climatic factors were higher in rainfall amount and sunshine hours than temperature. Only sunshine hours of climatic factors accumulated during the 160 DAFB had significant positive relationship ($r=0.68^*$) with fruit diameter 160 DAFB. Between full bloom date and fruit diameter 160 DAFB had no significant relationship. Fruit growth in 2004, as continuous rain fall and short sunshine hours, showed opposite pattern compared to that in 2009. Therefore, fruit growth of 'Niitaka' pear was more influenced by the accumulated sunshine hours than accumulated temperature.

• Current Research on Agriculture and Life Sciences
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• v.20
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• pp.99-105
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• 2002

To develop good soybean varieties for sprouts. 285 indigenous lines and 16 recommending varieties were evaluated by the sprout and agronomic characteristics. The range of whole length, hypocotyl length, root length, and yield rate of sprouts was 9.5~23.0cm, 5.9~15.1cm, 3.2~9.2cm, and 121~695%, respectively. Yield rate of sprouts was the highest, 409%, in the lines of mixed seed coat color. At the same time, it was reversely proportional to seed weight : the smaller the seed weight, the higher the yield rate as in all other reports. The number of roots was significantly fewer in the lines of the black and the green seed coat color than others. Based on whole length, rate of root length, and yield rate of sprouts, many indigenous lines were evaluated much better than recommending varieties. In the hypocotyl color of sprouts, the brightness was higher in improved variety than indigenous lines but vice versa in redness and yellowness in general.

• Current Research on Agriculture and Life Sciences
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• v.20
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• pp.1-8
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• 2002

This study was conducted to obtain the information of varietal development using wild soybean through investigation of variation and heredity of major agronomic characters in $F_2$ generation of interspecific cross between Glycine max and G. soja. In segregating populations of two crosses, all characters observed except 100-seed weight showed transgressive segregation. Days to flowering showed normal distribution; mean days to flowering in $F_1$, and $F_2$ was approximately mean of parent. Mean of $F_1$ for 100-seed weight was 6.2g and 5.7g for Eunhakong/KLG10084 and Sohaegnamulkong/KLG10084, respectively, which were somewhat skewed distribution to small seeded parents. Mean seed yield of $F_2$ was about mean of two parents. Degree of vine was 6.4 and 5.7 in $F_1$ for two crosses but it was 6.0 in $F_2$ for Eonbakong/KLG10084, which revealed the degree of vine as partial dominance while 4.6 for Sobaegnamulkong/KLG10084, somewhat different results from the previous cross. Broad-sense heritability($h^2B$) for plant height, days to flowering, pods per plant, seed yield, and degree of vine was comparatively high and narrow-sense heritability($h^2B$) for 100-seed weight which is the moot important character in the development of small seed-size sprout soybean was 52.3% and 65.6% for Eunhakong/KLG10084 and Sohaegnamulkong/KLG10084, respectively, which indicated that selection for the character in early generation was possible.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.55-60
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• 2015

Skin blackening is a serious postharvest disorder occurring in 'Fuyu' persimmon fruits (Diospyros kaki, 'Fuyu'). Phenolic content, polyphenol oxidase (PPO) and peroxidase (POD) activity, and lipid saturation were investigated in skin tissue of 'Fuyu' fruits. The phenolic compounds were accumulated unevenly on fruit skin depending on sunlight exposure, i.e., the most accumulation on sunny side and the least on the opposite, shaded side. The fruits harvested from shaded branches inside the canopy showed relatively even distribution of phenolic compounds in the skin. The activity distribution of PPO and POD were also uneven but only in fruits suffering f rom skin b lackening disorder, w ith the h ighest and the lowest a ctivity of PPO and P OD, respectively, in the blackened area of the fruit. When the sunny, southern sides of fruits were marked at harvesting time and fruits were stored at low temperature, a round black spot, as a symptom of skin blackening disorder, developed during storage exactly on the marked region. In addition, the sunny side of fruit showed higher lipid saturation, thus indicating adaptation to high temperature caused by the sunlight. These results suggest that the skin blackening disorder of 'Fuyu' fruits can be considered as a kind of chilling injury symptom that develops on the high-temperature-acclimated skin tissue of sunlight-exposed fruits when they are later exposed to low temperature.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.263-268
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• 2008

Estimates of genetic gain (in volume growth) and diversity (expressed as status number, $N_s$) were determined in a clonal seed orchard of Pinus koraiensis. The genetic thinning was based on clonal breeding values (represented by general combining ability) obtained from progeny tests, clonal fertility estimated by strobilus production, and clonal size variation determined by the ramet numbers per clone. Parental GCA values for volume growth were calculated, based on height and diameter at breast height measured from field trials. Clonal fertility was estimated from the assessments of strobilus production over twelve years from 1991 to 2003, and used for the calculation of status number. There are 179 clones and 5,268 ramets in 12ha area of P. koraiensis clonal seed orchard. Genetic gain and diversity estimates were determined under assumptions of 30% pollen contamination and inferior genetic value of contaminating pollen. Genetic gain increased as thinning rates were set from 10% to 60%. However, for the higher thinning intensities, the increase of genetic gain was not remarkable. Genetic thinning by means of truncation selection resulted in a greater genetic gain but a large decrease in status number. Status number was represented around 40 clones for 10% through 60% thinning intensities, but for the higher thinning intensities, it was a bit fluctuated. Based on the present results, it could be concluded that thinning rate should not be stronger than 60% to optimize genetic gain while conserving genetic diversity. Consequently 50% or 60% thinning rate might be appropriate for genetic thinning in the clonal seed orchard of P. koraiensis. The effect of pollen contamination on the genetic gain and the consequence of genetic thinning for seed production in the clonal seed orchard, and seed orchard management scheme were also discussed.

• Geophysics and Geophysical Exploration
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• v.13 no.2
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• pp.137-143
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• 2010

An earthquake with local magnitude $(M_L)$ 3.7 on December 9, 2000 occurred offshore Yeongdeok area, South Korea. In case of applying Chang and Baag (2006) crustal velocity model, the epicenter is $36.4462^{\circ}N\;and\;129.9789^{\circ}E$, which belongs to the inside of the Korean Peninsula Continental Shelf. Although we use the modified model reducing crustal thickness of Chang and Baag (2006) model by 5 km considering the transition from continental crust to oceanic crust in the East Sea, the epicenter was little changed. We carried out the waveform inversion analysis to estimate focal depth and focal mechanism of this event. The focal depth is estimated to be 11 ~ 12 km. The seismic moment is estimated to be $1.0{\times}10^{15}N{\cdot}m$, and this value corresponds to the moment magnitude $(M_W)$ 3.9. The offshore Yeongdeok event including May 29, 2004 offshore Uljin one show typical thrust faulting, and the direction of P-axis is ESE-WNW. The moment magnitude estimated by the spectral analysis is 4.0, which is similar to that by the waveform inversion analysis. Average stress drop is estimated to be 3.4 MPa.

• Korean Journal of Plant Taxonomy
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• v.35 no.1
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• pp.7-23
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• 2005

Molecular phylogenetic studies were conducted to evaluate interspecific relationships in 40 populations of Viola including 35 Korean taxa, four Japanese populations and one outgroup using nuclear ribosomal ITS sequences. The phylogenetic analyses were conducted using parsimony and neighbor-joining methods. Subsection Trigonocarpae of section Nomimium appeared as the most basal clade within the Korean Viola. Section Dischidium and Chamaemelanium was monophyletidbootstrap 100%) and placed between subsect. Trigonocarpae and three other subsections of sect. Nomimium. Sect. Nomimium was paraphyletic. Although each subsectional grouping was in accordance with previous infrageneric classification based on morphological characters, yet discordance remained at the series level. Two evolutionary trends observed in the ITS tree were as follows. First, subsect. Trigonocarpae(x=10) was derived from the outgroup(x=6); Second, subsects. Bilobatae and Vaginatae(x=10 or 12), and subsect. Patellares(x=12) of sect. Nomimium were originated from sects. Dischidium and Chamaemelanium(x=6). Viola albida complex including three very closely related taxa was recognized as independent group within subsect. Patellares in parsimony tree. This result suggested that they should be treated as a taxa in series Pinnatae. Phylogenetic position of a putative hybrid species, Viola woosanensis was not supported with previous morphological hypothesis.

• Korean Journal of Plant Resources
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• v.22 no.2
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• pp.128-135
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• 2009

In this study, the selected 789 lines having agronomic values out of over 2,500 mungbean (Vigna radiata (L.) Wilczek) germplasms, examined the 27 characters including hypocotyl color and leaf size of 401 lines in 2005 and of 388 lines in 2006, and analyzed the contents of vitexin and isovitexin in these mungbean germplasms. The average contents of vitexin and isovitexin in mungbean of the 401 lines used in 2005 were 8.71($1.1{\sim}13.4$) and 9.54($0.9{\sim}15.9$) mg/g, respectively, and the correlation coefficiency ($R^2$) of the contents of vitexin and isovitexin was 0.958. Nine lines including VC3890B were selected to be the ones containing high vitexin and isovitexin. The average contents of vitexin and isovitexin in mungbean of the 388 lines used in 2006 were 10.17($2.0{\sim}15.9$) and 10.64($0.2{\sim}17.6$) mg/g, respectively, and the correlation coefficiency ($R^2$) of the contents of vitexin and isovitexin was 0.958. Six lines including VC4096-2B-4-B-2-B were selected to be the ones containing high vitexin and isovitexin. The contents of vitexin and isovitexin were higher in the mungbean with larger leaves and longer ripening period out of the main characters.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.577-589
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• 2021

Soil seed bank community contributes to the long-term conservation of plant diversity and vegetation dynamics, and their decreasing diversity and density with soil depth provide critical perspectives (deterministic and stochastic) for understanding the community disassembly process. We analyzed changes in species composition and diversity and structuring patterns by soil layer (top and bottom), including surface vegetation, in Gwangneung Forest, a mature forest with a vegetation climate in the temperate central part of the Korean Peninsula. From two layers of soil collected with a vertical difference of 10 cm, 934 specimens of 27 families, 40 genera, 44 species, three varieties, and 47 taxa, germinated. Although species diversity and germination density decreased in most comparative characteristics, including growth type, there was no statistical significance due to large deviations. Within-group variability of species composition was similar in the upper and lower soils, as was the decline pattern in co-occurred species (ζ-diversity) and change in species retention probability. The structuring process of the community composition in the two soil layers was fitted with an exponential correlation rather than a power function, demonstrating the dominance of the stochastic process. The pattern in diversity and species turnover according to soil depth in Gwangneung Forest was discovered to be structured by stochastic random events, such as seed vertical movement rather than interaction with trait characteristics.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.449-462
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• 2021

We analyzed the effects of temperature on the survival, development, and reproduction of the non-diapause Asian corn borer, Ostrinia furnacalis (Lepidoptera: Crambidae). A 16:8 h light:dark photoperiod was supplied to the non-diapause stages of O. furnacalis. The insects were raised on an artificial diet at seven constant temperatures between 15 and 35℃ for immature stages, and eight temperatures between 13 and 33℃ for the adult stage. The survival rate of eggs exceeded 70% at all temperatures, whereas survival of larvae was as low as 7.4% at 15℃. The developmental periods of the immature stages decreased with increasing temperature, but the larval period did not decrease further at 35℃. The pupal weight increased with increasing temperature, but the female weight decreased at 35℃. Variations with different last larval instars within the colonies at different temperatures were observed. Adults produced offspring at all tested temperatures. Adult longevity and the pre-oviposition and oviposition periods decreased with increasing temperature, but the pre-oviposition period increased at 33℃. Total fecundity exceeded 400 viable eggs at 22℃ and 31℃. The mean daily fecundity during the oviposition period and the mean daily fecundity on the day of oviposition increased with increasing temperature, but decreased at 33℃. Daily fecundity sharply increased at earlier adult ages and slowly decreased thereafter. The simulated oviposition frequency was greatest at 22℃. The lower developmental threshold temperatures were estimated to be the lowest at 9.7℃ for the first instar larva and the highest at 14.7℃ for the 5th to last instar larval stage, using a linear model.