• Korean Journal of Soil Science and Fertilizer
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• v.47 no.1
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• pp.16-22
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• 2014

This study was conducted to determine the changes in soil chemical properties and the growth of seedling according to the different dredged soil improving methods at slope of Saemangeum sea dike. Undersea dredged soil was improved by five different methods. Seedlings of Ulmus davidiana var. japonica, Chionanthus retusa, Celtis sinensis, and Pinus thunbergii were planted after 9 month of experience site installation, then soil pH, NaCl concentration in soil, soil organic matter (SOM), and survival rate and height of seedling was measured. Initial soil pH was highest in the control plot but it decreased to the similar level with other soil improving plots after 35 months. There were no differences in NaCl concentration between the control and soil improving plots, and it showed decreasing tendency during the study period. In the control plot, initial SOM was lowest among that of other plots during the study period. The survival rate of 36 months after planting of P. thunbergii was highest among the species. The gap of the tree growth of P. thunbergii between the control plot and the soil improving plots was small, however, other species showed relatively higher tree height in the soil improving plots than the control plots. Creation forest with P. thunbergii might be a cost effective afforestation in coastal reclaimed land since it rarely needs additional improvement of dredged soil.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.112-117
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• 2011

This research was conducted to determine the effect of the pre-treatment of mulberry charcoal on the salt tolerance response in Kentucky bluegrass 'Perfection'. As this results, 400 mM NaCl treatment reduced turf growth such a fresh and dry weight, and induced physiological damages like decreased chlorophyll content and increased electrolyte leakage. The pre-treatment of mulberry charcoal, however, mitigated those growth and physiological responses associated with NaCl stress, regardless of the concentrations of charcoal solution. Furthermore, it was observed that higher K ion concentration by mulberry charcoal pre-treatment reduced Na ion in shoot. This research suggests to be a possibility of planting turf grasses in reclaimed land or higher salt accumulated area using a mulberry charcoal treatment.

• Journal of Radiation Industry
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• v.4 no.4
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• pp.307-312
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• 2010

Plants have evolved physiological, biochemical and metabolic mechanisms to increase their survival under the adverse conditions. This present study has been performed to select salt-tolerant rice mutant lines through in vivo and in vitro mutagenesis with gamma-rays. For the selection of the salt-tolerant rice mutants, we conducted three times of selection procedure using 1,500 gamma ray mutant lines resulted from an embryo culture of the original rice cv. Dongan (wild-type, WT): first, selection in the a nutrient solution with 171 mM NaCl; second, selection under in vitro condition with 171 mM NaCl; and third, selection in a reclaimed saline land. Based on a growth comparison of the entries, out of the mutant lines, two putative 2 salt tolerant (ST) rice mutant lines, ST-87 and ST-301, were finally selected. The survival rate of the WT, ST-87 and ST-301 were 36.6%, 60% and 66.3% after 7 days in 171 mM NaCl treatment, respectively. The WT and two salt tolerant mutant lines were used to analyze their genetic variations. A total of 21 EcoRI and Msel primer combinations were used to analyze the genetic relationship of among the two salt-tolerant lines and the WT using the ABI3130 capillary electrophoresis system. In the AFLP analysis, a total of 1469 bands were produced by the 21 primer combinations, and 700 (47.6%) of them were identified as having polymorphism. The genetic similarity coefficients were ranged from 0.52 between the ST-87 and WT to 0.24 between the ST-301 and the WT. These rice mutant lines will be used as a control plot for physiological analysis and genetic research on salt tolerance.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.3
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• pp.171-178
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• 1998

This experiment was conducted to study on forage utility of Diplachne fusca L. which live in reclaimed saline land of midwest region of Korea. The primary experiment was conducted to know on germination characteristics of Diplachne fusca L. according to storage condition after seed harvesting, light, temperature, flooding depth, salinity and soil covering. The results obtained are summarized as follows; 1. The germination percentage, average days to germination, germination rate and coefficient of germination were not different in existence of light, combination with existence of light and storage condition, but those were higher different in storage condition. 2. The germination characteristics were more higher on the condition of alternating temperature than constant temperature, and it was the highest on the condition of alternating temperature with $35/25^{\circ}C$ and constant temperature with $35^{\circ}C$. 3. There were apparently significant in germination percentage, average days to germination, germination rate and coefficient of germination according to flooding depth. The germination characteristics of D. fusca L. were the highest on the wndition of flooding depth with Ocm and did not germinate on the condition of flooding depth more than 3cm. 4. There were apparently significant in germination percentage, average days to germination, germination rate and coefficient of germination according to salinity. Germination characteristics were the highest on the condition of salinity with 0.2%. There was more than 30% of germination percentage on the condition of salinity with 1% SO Diplachne fuaca L. was suitable to cultivate in reclaimed saline land. 5. The germination percentage, average days to germination, germination rate and coefficient of germination were significantly difference between soil covering. So Germination characteristics were the highest on the condition of soil covering with 0.2cm. But they scarcely germinated on the condition of more than 1cm of the soil covering.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.3
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• pp.179-186
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• 1998

This experiment was conducted to study on forage utility of Diplachne fusca L. which live in reclaimed saline land of midwest region of Korea The secondary experiment was conducted to know on growth characteristics, forage yield and forage value of Diplachne fusca L. in order to get a necessary data on possible utilization of native plant as a forage crop and practical use of reclaimed saline land. The results obtained are summarized as follows; 1. The growth of Diplachne fusca L. was neary finished at heading stage. So plant height, leaf length, leaf width, stem diameter, tillering number, fresh weight and dry weight per plant were 137.5cm, 42.6cm, 4.65mm, 2.48mm, 15.3 tiller, 44.68 and 15.3g respectively. 2. Fresh weight was the highest with 4,460kg/10a at heading stage, dry weight was 1,530kg/10a at heading stage and 1,630kg/10a at 20 day after heading. The fresh weight was significantly difference between cutting height level according to cutting time, but total fresh weight was not significantly difference between cutting height level. Total dry weight was significantly difference between cutting height, so it was a large yield at cutting height of 10cm. 3. The contents of crude protein, available protein, digestible protein and TDN were the range of 12.3~3.7%, 12.3~3.7% 10.8~3.6% and 65.2~60.7% according to growth stage, respectively. The highest yield of crude protein, available protein, and digestible protein were showed at heading stage, that of TDN showed at 20 day after heading. The contents of ADF and NDF were the range of 36.4~50.0% and 62.7-80.5% according to growth stage. 4. The contents of P, Ca, K and Mg were the range of 0.31~0.20, 0.70~0.52, 1.74~1.28 and 0.19~0.18% according to growth stage, respectively. The highest yield of P, Ca and K was showed at heading stage, that of Mg showed at 20 day after heading. 5. The contents of ENE, NEL, NEM and NEG were the range of 1.42~1.29, 0.68~0.62, 0.68~0.61 and 0.40~0.35 McaVlb according to growth stage, respectively. The highest yield of ENE, NEL, NEM and NEG was showed at 20 day after heading by inuease after heading. 6. The grasseating ratio of Diplachne fusca L. of before and after heading by milk cattle was 96.5% and 95.3%, respectively.

• Korean Journal of Weed Science
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• v.12 no.4
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• pp.335-351
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• 1992

The identification of green algae which were collected from paddy rice fields of the whole nation was conducted in 1991, and also the reproduction processes of three important green algae were investigated. The green algae identified were 46 species in 16 families including 4 species in the Volvocaceae, 4 species in the Palmellaceae, 3 species in the Ulotrichaceae, 3 species in the Oocystaceae and 6 species in the Scenedesmaceae. It was recognized that the algae which have caused a large injury to the flooded direct-seeded rice in Seosan reclaimed saline land was the genus Cladophora. The green water blooms on paddy water were induced mostly by the concentrated populations of suspended green algae such as the genera, Chlamydomonas and Stichococcus. A rapid propagation of Hydrodictyon was resulted from the asexual reproduction forming autocolony in each mother cell. The sexual and asexual reproduction processes of Oedogonium and the sexual reproduction process of Spirogyra were observed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.2
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• pp.85-90
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• 2013

This study was conducted to examine the basis for the information to select the suitable potato varieties grown in new reclaimed land. The potatoes of five varieties were planted in the port with 4 different electrical conductivities of saturated extracts of soil taken the Saemangeum reclamation area, which was made of non-treatment salt and three concentrations of salt treatment, 1.6 dS $m^{-1}$, 3.2 dS $m^{-1}$, 4.8 dS $m^{-1}$, respectively. All of the potato varieties were uniformly emerged without missing plant in all treatment groups, even 4.8 dS $m^{-1}$ treatment group. According to the salt concentration of soil, required date to the emergence of the potato comparing to non-treatment salt was delayed 3-4 days in 1.6 dS $m^{-1}$, 6-10 days in 3.2 dS $m^{-1}$, 7-13 days in 4.8 dS $m^{-1}$, respectively, and the number of its branch decreased by 14-58% comparing to non-treatment salt depending on varieties. Since the increase of the salt concentration of the soil was more serious the decrease of the number of its branch, but plant height tended to increase when branch number per plant was small, which was depending on more number of its branch than salt concentration. Fresh tuber yield of potato comparing to non-treatment salt were decrease 33.7% in 1.6 dS $m^{-1}$, 59.5% in 3.2 dS $m^{-1}$, 79.3% 7-13 days in 4.8 dS $m^{-1}$, respectively. The threshold EC starting the growth inhibition of fresh weight decreased was 1.2 dS $m^{-1}$ for Chudong, 1.8 $m^{-1}$ for Chubeak, 1.9 $m^{-1}$ for Chugang and Chuyeong, and 2.0 $m^{-1}$ for Sumi, and EC which decreased 50% of dry weight index was 2.4 dS $m^{-1}$ for Chubaek, 2.45 dS $m^{-1}$ for Chudong, 2.81 dS $m^{-1}$ for Chugang, 3.03 dS $m^{-1}$ for Chuyeong, and 3.29 dS $m^{-1}$ for Sumi. The present results suggest that Sumi is considered to the suitable potato variety grown on saline soils.