• Korean Journal of Weed Science
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• v.9 no.1
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• pp.56-68
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• 1989

aA series of experiments were conducted to investigate the effect of plant growth regulator treatments on the growth and lateral root formation in soybean sprouts in order to establish the effective method of producing root-less or short-rooted soybean sprouts with larger diameter in the hypocotyl. Major results can be summarized as follows. 1. Soybean sprouts showed fairly uniform elongation rate from 3 to g days after imbibition with daily increase of 3.8cm. The speed of elongation of hypocotyl was reduced whereas that of root accelerated 7 days after imbibition. Lateral roots began to emerge fairly evenly from 5 to 9 days after imbibition with a daily increase of 4.4. 2. Auxins(IAA, IBA, NAA, 2,4-D) inhibited hypocotyl elongation and formation of lateral roots and increased hypocotyl diameter without influencing root length and hook diameter at higher concentrations. The dry weight of cotyledon was increased significantly as compared to that of hypocotyl and root. Among the tested auxins, 2, 4-D was the most effective. 3. BA and 4PU-30 significantly reduced elongation of hypocotyl and root and resulted in the biggest diameter of hypocotyl when treated at higher concentrations. The lowest effective concentration of BA to prevent the formation of larval gal roots was 12.5ppm. The formation of lateral roots could be completely prevented by BA and 4PU-30 treatment but kinetin, zeatin, zeatin riboside resulted in many lateral roots and increased thickness of soybean sprouts with little influence. Cotyledon deformation was found in soybean sprouts treated by 4PU-30. 4. 2, 4-D was the most effective for increasing the hypocotyl diameter while 4PU-30 was the most effective for reducing no. of lateral roots. 5. It can be concluded that among the plant growth regulators tested, BA was effective in reducing root length and increasing hypocotyl diameter. BA 12.5 ppm or 15 ppm may thus be the more practical for production of soybean sprouts. 6. ABA showed no significant effect of growth parameter, however ABA 25 ppm inhibited only no of lateral roots with little influence on the growth of seedling. 7. Ethephon inhibited the elongation of hypocotyl and root and increased hypocotyl diameter at higher concentrations. 8. The combined effect of cytokinins and ethephon was very similar to result of BA treatment alone. As the ethephon concentration increased, hypocotyl diameter and dry weight of cotyledon tended to increase.

• Korean Journal of Environmental Agriculture
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• v.20 no.4
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• pp.297-302
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• 2001

To compare the relationship between the vertical distribution of heavy metals in paddy soil and soil pH near four abandoned metal mines, 40 paddy surface soils $(0{\sim}15\;cm)$ and 12 soils with soil depths ($0{\sim}20$, $20{\sim}40$, $40{\sim}60$, $60{\sim}80$ and $80{\sim}100$ cm) were collected. Both total and extractable heavy metal contents in soils were analyzed after acid digestion $(HNO_3:HClO_4:H_2SO_4)$ and 0.1 N-HCl extraction, respectively. The 0.1 N-HCl fraction ratio over total contents of Cd, Cu, Pb, and Zn were 57, 30, 23, and 19% respectively. Vertical distribution of heavy metals varied considerably among the different mines. In Choil mine, there was no difference in concentrations of all the metals with soil layers. However, Cu and Pb contents in Gahak mime were high at $0{\sim}20\;cm$ depth, and Zn was high at $0{\sim}40\;cm$ depth. In Sinyemi mine, Cd and Cu contents were high at $0{\sim}40\;cm$ depth. Cd, Cu, and Pb contents in Okcheon mine were high through all soil profiles up to 100 cm soil depth. The 0.1 N-HCl fraction ratio over total contents of heavy metals with soil layers were very high at $0{\sim}20\;cm$ depth. As soil depth increased, fraction ratio of heavy metals decreased at the high soil pH (Gahak, Sinyemi, and Choil mines). However, the ratios of Cd, Cu, and Pb in Okcheon mine, having a relatively lower soil pH than other sites, were relatively similar through all the soil profiles up to 100 cm soil depth. Therefore, it was estimated that the mobility and availability of heavy metals in soils were affected by soil pH.

• Journal of Food Hygiene and Safety
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• v.30 no.1
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• pp.59-64
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• 2015

This study compared the content change of physiological active substances according to the extraction condition when we generally drink the extractive of Schisandra fruit with using water. Physiological active substances of the Schisandra fruit, schizandrin, gomisin A and gomisin N were analysed with HPLC. The results of extracting 1 dose of the Schisandra fruit tea, which is some as 1 g of Schisandra fruit, in 100 mL of water by differing the extraction type, extraction temperature and extraction time were of the followings. The total content of schizandrin, gomisin A and gomisin N of powder type in $26^{\circ}C$ leaching was the highest (p < 0.05) as the leaching content of 24 hours (5.54 mg/g) showed difference with different times and the contents of raw type Schisandra fruit were less than 0.1 mg/g in all of extraction time. The contents of powder type Schisandra fruit in $60^{\circ}C$ heating extraction was over 4.50 mg/g except for the 5 minute (2.94 mg/g), and the contents of raw Schisandra fruit were less than 0.3 mg/g. In case of $100^{\circ}C$ heating extraction, the contents of powder type Schisandra fruit showed over 5.10 mg/g in every time zone, and the raw type Schisandra fruit was less than 1.0 mg/g.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.4
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• pp.282-290
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• 1992

Based on surplus production models using fishery data for the last 20 years, a stock assessment was conducted for the small yellow croaker in Korean waters. The maximum sustainable yields (MSY) from the Schaefer and Fox models were estimated to be 37,000 metric tons (mt) and 33,450 mt. Zhang's model using time-series biomass with instantaneous coefficients of fishing mortality (F) and using time-series biomass and catch yielded MSY estimates of 45,328 mt and 40,160 mt, respectively. A yield-per-recruit analysis showed that the current yield per recruit of about 20g with F= 1.11 $yr^{-l}$, where the age at first capture $(t_c)$ is 0.604, was much lower than the maximum possible yield per recruit of 43g. Fixing $t_c$ at the current level and reducing fishing intensity (F) from 1.11 $yr^{-l}$ to 0.4 $yr^{-l}$ yielded only a small increase in predicted yield per recruit, from 20 to 25g. However, estimated yield per recruit increased to 43g by increasing $(t_c)$ from the current age (0.604) to age three with F fixed at the current level. This age at first capture corresponded to the optimal length which was obtained from the $F_{0.1}$ method. According to the analysis of stock recovery strategies employing the Zhang model, the optimum equilibrium biomass $(B^*_{MSY})$ which produces the maximum yield could be achieved after approximately five years at the lower fishing intensity (F=0.5).

• Korean journal of applied entomology
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• v.53 no.2
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• pp.149-156
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• 2014

The resistance levels of the green peach aphid, Myzus persicae (Sulzer), against 10 insecticides was checked and selected the applicable insecticide resistance markers. We conducted our study in 5 cabbage cultivation regions (Pyeongchang, Hongcheon, Bongwha, Muju, and Jeju) of Korea, over 3 successive years (2009-2011). We selected a multi-resistant (MR) strain from among the 5 field-collected populations. We analyzed esterase over-expression and mutation(s) in the target sites, by using native isoelectric focusing (IEF) and quantitative sequencing (QS). We detected esterase over-expression and StoF mutation in the acetylcholinesterase 1 gene (ace1) in all of the field-collected populations, including the MR strain. We did not detect the LtoF mutation, which is a well-known knockdown resistance (kdr) mutation in the para-type sodium channel gene (para), in the MR strain; however, the value of the MR strain for bifenthrin was 3,461-fold higher than that of the susceptible strain. Our results indicate that insecticide resistance is more effectively evaluated using molecular markers than by conducting a bioassay. The molecular markers StoF in ace1 and MtoL in para can easily be applied in diagnostic methods such as QS or PCR amplification of specific alleles (PASA). These methods may be extended to management of M. persicae resistance in the field.

• Journal of Life Science
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• v.13 no.5
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• pp.596-603
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• 2003

Cells respond to an accumulation of unfolded proteins in the endoplasmic reticulum (ER) by increasing transcription of genes encoding molecular chaperones and folding enzymes. The information is transmitted from the ER lumen to the nucleus by intracellular signaling pathway, called the unfolded protein response (UPR). To obtain genes related to UPR from B. mori, the cDNA library was constructed with mRNA isolated from Bm5 cell lines in which N-glycosylation was inhibited by tunicamycin treatment. From the cDNA library, we selected 40 clones that differentially expressed when cells were treated with tunicamycin. Among these clones, we have isolated ATFC gene showing similarity with Hac1p, encoding a bZIP transcription factor of 5. cerevisiae. Basic-leucine zipper (bZIP) domain in amino acid sequences of ATFC shared homology with yeast Hac1p. Also, ATFC is up-regulated by accumulation of unfolded proteins in the ER through the treatment of ER stress drugs. Therefore we suggest that ATFC represents a major component of the putative transcription factor responsible for the UPR leading to the induction of ER-localized stress proteins.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.1
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• pp.183-192
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• 2015

This study aimed to produce fermented extracts with sugar made from lotus root (LR) and Platycodon grandiflorum (PG), using lactic acid fermentation, and confirmed their physiological and anti-oxidative activities as basic data for manufacturing functional drinks through sensory tests. For the final sugar concentrations, PG showed $48.1^{\circ}brix$ and LR showed $52.0^{\circ}brix$. Sugar concentrations during lactic acid fermentation following dilution of sugar to $12^{\circ}brix$, ranged from $11.5{\sim}12.1^{\circ}brix$ for PG and $11.9{\sim}12.4^{\circ}C$ for LR. During lactic acid fermentation, lactic acid bacteria numbers tended to decrease in both fermented LR and PG extracts with sugar as the fermentation period increased. For DPPH radical scavenging ability, LR was three times higher in control without lactic acid fermentation while PG showed significant increases in L. acidophilus (77%), L. brevis (90%), and L. delbrueckii (177%) during lactic acid fermentation. For total polyphenol content, LR showed a higher concentration than PG, and except for fermented L. delbrueckii extract showing similarity with the control, contents of fermented extracts decreased. In the case of PG, CUPRAC, increased significantly in L. brevis, whereas FRAP, increased significantly in L. delbrueckii with lactic acid fermentation. For reducing power, except for fermentation with L. brevis, all PG showed lower reducing power activities. In the sensory test of fermented LR and PG extracts with sugar, both fermented extracts showed better results with L. brevis or L. delbrueckii than control or those with L. acidophilus in every item. Based on these results, it is highly possible to develop fermented extract drinks with sugar using LR or PG. In particular, lactic acid bacteria such as L. delbrueckii and L. brevis showed generally higher activities with potential as a functional drink.

• Food Science and Preservation
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• v.21 no.1
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• pp.129-139
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• 2014

This study was conducted in order to investigate the optimal fermentation periods of the Smilax china L. leaves as a fermented tea via Aspergillus oryzae for 0 (non-fermented), and 10, 20, and 30 days (NF, F10, F20, F30). It was also observed for its quality characteristics. In the color and spectrum (400~700nm) of 1% tea water extract, NF was light yellow, whereas fermented tea (F10~F30) was light red color, and the F10 among F10~F30 has the clearest color and spectrum. Furthermore, acceptabilities of aroma and brightness were insignificantly different between NF and F10~30, while the mouth feel and overall acceptabilities were insignificantly distinct among all of the fermented teas. Therefore, these results suggest that the appropriate fermentation period for tea fermentation is 10 days. On the other hand, the total polyphenol and flavonoid content in the NF was the highest among all of the fermented teas. In the antioxidant parameters, EDA (electron donating ability), FRAP (ferric reducing antioxidant power), and LPOIA (lipid peroxidation inhibitory activity) in the NF were the highest among all fermented teas. Meanwhile, the XOI (xanthine oxidase inhibitory activity) was low, as well as insignificantly different from NF and F10~F30, whereas the AOI (aldehyde oxidase inhibitory activity) was markedly higher (38.09~41.70%) by the hot water tea extract (with or without fermentation), particularly the AOI that has increased via fermentation. In conclusion, the overall antioxidant activity tended to be reduced by fermentation; however, the EDA, FRAP and LPOIA in the fermented tea for 10 days was higher than the activities during 20~30 days of fermentation. There was a similar result in the color and acceptability of fermented tea for 10 days, which was remarkably better than those of 20-30 days. Therefore, fermented tea from the leaves of Smilax china L. could be expected to be used as a functional tea without the loss of inhibitory activity of both the XO and AO via fermentation.

• Journal of Korean Society of Forest Science
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• v.110 no.3
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• pp.341-354
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• 2021

A large part of Gapyeong is occupied by Korean pine (Pinus koraiensis) and Japanese larch (Larix kaempferi) plantations. Abies holophylla stands are scattered throughout Gapyeong, but little information on their distribution is available. This study explored the potential of succession from planted species to native A. holophylla in plantations. Trees were inventoried and regeneration of A. holoplhylla and stand management history were examined in Korean pine, Japanese larch, and A. holophylla-dominated stands. The importance percentage of A. holophylla was the highest among species with a range of 36.1% to 79.1% in all stands and the density of A. holophylla in understory (DBH <2 cm or <1.3 m height) ranged from 50 to 5,820 trees ha^-1. Non-metric multidimensional scaling classified stands into four types, AN, AP, AM, and P. The AN type showed a reverse J-shape DBH distribution, which was similar to that in natural A. holophylla stands. Both AP and AM types included Korean pine plantations with A. holophylla seed trees within stands. For AP, A. holophylla competed with planted species in overstory and deciduous broadleaved species in understory. The AM type was once thinned from below, thus stem density in the mid DBH classes was lower than upper or lower DBH classes. The P type consisted of plantations without A. holophylla seed trees. However, understory regeneration of A. holophylla was abundant through seed supply from A. holophylla in adjacent stands. Plantations with A. holophylla seed trees within or in adjacent stands showed vigorous natural regeneration of A. holophylla, highlighting the potential for succession from planted species to native A. holophylla in the Gapyeong area. Further studies can help develop techniques to restore plantations to native species-dominated natural stands using ecological succession.

• Journal of Korea Water Resources Association
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• v.55 no.1
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• pp.1-10
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• 2022

Irrigation water supplied to the paddy field is consumed in the amount of evapotranspiration, underground infiltration, and natural and artificial drainage from the paddy field. Irrigation return flow is defined as the excess of irrigation water that is not consumed by evapotranspiration and crop, and which returns to an aquifer by infiltration or drainage. The research on estimating the return flow play an important part in water circulation management of agricultural watershed. However, the return flow rate calculations are needs because the result of calculating return flow is different depending on irrigation channel water loss, analysis methods, and local characteristics. In this study, the irrigation return flow rate of agricultural watershed was estimated using the monitoring and SWMM (Storm Water Management Model) modeling from 2017 to 2020 for the Heungeop reservoir located in Wonju, Gangwon-do. SWMM modeling was performed by weather data and observation data, water of supply and drainage were estimated as the result of SWMM model analysis. The applicability of the SWMM model was verified using RMSE and R-square values. The result of analysis from 2017 to 2020, the average annual quick return flow rate was 53.1%. Based on these results, the analysis of water circulation characteristics can perform, it can be provided as basic data for integrated water management.