• Journal of Life Science
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• v.20 no.10
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• pp.1468-1475
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• 2010

Sulfate reduction rates (SRR) using $^{35}SO_4^{-2}$, sulfide producing rates (SPR) using gas chromatography, the number of sulfate reducing bacteria (SRB) using the most probable number (MPN) method, and soil components (moisture, ammonium, total nitrogen, total organic carbon, total carbon, total inorganic phosphorus, total phosphorus, and sulfate) using standard methods in the organic/conventional rice paddy soils, cleaned/polluted reservoir soils, and cleaned/polluted foreshore soils were studied with the change of seasons. The average SRR was more related to the number of SRB and soil components (especially nitrogen and phosphorus) than sulfate concentration. SRR was also recorded to be highest in October soil samples. However, SPR was higher in foreshore soils containing a high concentration sulfate than in fresh water soils, and it was also recorded to be higher in the polluted areas than in clean areas. From these results, we can conclude that the SRR and SPR of anaerobic environments were affected by the number of SRB, soil components and temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.2
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• pp.113-118
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• 2016

This experiment was conducted to identify the variations in inorganic nutrients and plant growth in millet (Panicum miliaceum L.) due to soil salinity. The soil series was Munpo and soil texture was silt loam. The experimental soil was amended so that the soil had salinities of $0.8dS\;m^{-1}$, $1.6dS\;m^{-1}$, $3.2dS\;m^{-1}$ and $4.8dS\;m^{-1}$. Millet was transplanted 15 days after sowing. As soil salinity increased, the degree of reduced growth was in the order of seed production > root dry matter > plant dry matter > culm length > tiller number > stem thickness > Panicle length. Seed production was decreased to 18.9% in soil salinity of $1.6dS\;m^{-1}$, 36.9% in of $3.2dS\;m^{-1}$, and 50.7% in EC of $4.8dS\;m^{-1}$. Root dry matter decreased to 35.8% in EC of $3.2dS\;m^{-1}$, and to 40.5% in EC of $4.8dS\;m^{-1}$. As soil salinity increased, Total nitrogen content increased in all aboveground parts, roots and seeds. However, There was no difference in CaO, $P_2O_5$, $K_2O$ and, MgO in soils of different salinity. On the other hand, $Na_2O$ content was higher in the order roots> shoots> seed, and in the case of roots, $Na_2O$ content increased to 1.02% in soil salinity of $4.8dS\;m^{-1}$. However, up to soil salinity of $1.6dS\;m^{-1}$, the $Na_2O$ content of the seed was similar to that in plant grown in the Control conditions($0.8dS\;m^{-1}$). In conclusion, taking into consideration economic factors, millet could be cultivated in soil with salinities of up to approximately $1.6dS\;m^{-1}$, and seed produced from reclaimedland would be suitable for human consumption.

• Journal of Plant Biology
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• v.35 no.2
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• pp.135-142
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• 1992

Shoot tip explants from germinated seeds of Alnus hirsuta were cultured on NT (Nagata and Takebe, 1971) mineral salts medium supplemented with 6% glucose, MS (Murashige and Skoog, 1962) vitamin mixture, polyvinylpyrrolidone (PVP) and $0-50\;\mu\textrm{M}$ 6-benzylaminopurine (BAP). Five $\mu\textrm{M}$ BAP was found to give the highest shoot multiplication rate. Accordingly about 200 shoots were obtained for further experiments by multiplying shoots on this medium for 4-5 months. Regardless of carbon sources, NT mineral medium produced 3-12 times of shoots than MS mineral medium did. On NT mineral medium, 3% sucrose, 3% glucose and 6% glucose yielded no significant differences. It was observed that media consisting of 1/4-1/2 strength NT mineral salts, 3% sucrose and $1-8\;\mu\textrm{M}$ IBA produced about 100% rooting rate. Almost 100% of the resulting plantlets survived after transfer to the soil by decreasing humidity stepwise.epwise.

• Journal of Environmental Impact Assessment
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• v.31 no.5
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• pp.296-309
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• 2022

This study investigated the mobility of inorganic elements (As, Cd, Pb, and Zn) that existed as acid extractable and reducible forms in flooded soils with a pot experiment involving rice cultivation. In general, it is known that soil inorganic elements that existed as an acid extractable form which includes exchangeable, carbonates, non-specifically sorbed, and specifically sorbed have mobility. However, the result of the experiment revealed that each inorganic elements of rice roots grown from flooded soils had different characteristics. The concentrations of Arsenic existed as both forms and the concentrations of cadmium and lead existed as a reducible form in the soils showed a high causal relationship with the concentrations of those elements in the roots of rice plants. The concentrations of zinc, an essential plant element, didn't show a causal relationship. Therefore it is necessary to consider the soil's environmental characteristics such as drained/flooded condition, oxidation/reduction condition, etc. for the mobility assessment of inorganic elements. The concentrations of the reducible form of arsenic, cadmium, and lead in flooded environment such as a paddy field should be also considered because the mobility of these elements combined with Fe/Mn increases in the reduction condition.

• Journal of Bio-Environment Control
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• v.14 no.1
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• pp.38-45
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• 2005

This research was conducted to determine the effect of fertilization programs on crop growth, nutrient uptake and yield of strawberry and salt accumulation in PE film house soil. To achieve these, experiments were conducted through two years with various fertilization program such as traditional fertilization(A), recommended fertilization of Rural development administration (B), Tochigi prefectural experiment station (C) and Nonsan strawberry experiment station (D), and control (E). In 1st year, statistical differences in growth characteristics were not observed among treatments except (E). Yield per 10 was the highest in (D) followed by (A), (B), (C) and (E) and there was the statistical difference between (D) and (E). In the 2nd year experiment, growth characteristics and yield showed similar trends to those of 1st year experiment. In the results of soil analysis of 2nd year, the soil pH of all treatments were in the acceptable range, while electrical conductivity of (A) and (D) were 2.36 and 2.19 %$dS{\cdot}m^{-1}$, respectively. After finishing of strawberry cultivation, nitrate concentration in soil solution of (A) and (D) were 74.6 and 65.0%$mg{\cdot}L^{-1}$ and Na in those were 3.71 and 3.53 $cmol+kg^{-1}$, respectively. Above results indicated that (A) and (D) were good fertilization program for strawberry cultivation, but those also resulted in accumulation of $NO_{3-}N$ and Na in PE house soil.

• Journal of Bio-Environment Control
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• v.11 no.3
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• pp.121-126
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• 2002

This study was conducted to investigate the effect of high concentration of sodium salts and chlorides in soil on the growth of tomato and the uptake of minerals. The growth inhibition rates of plant height and dry weight were different depending on salts, but they were not related to the electric conductivities (EC) and acidities (pH) in the soil solution. The orders of growth inhibition were Cl, SO$_4$, CO$_3$, PO$_4$＞NO$_3$ in the sodium salts series, and Na, K, Mg, NH$_4$＞Ca in the chlorides. The growth inhibition rates of the sodium salts series tended to be larger than those of the chloride series. Yield was lower 30%~10% in the sodium salt and chloride series than in the control. Chlorophyll content, photosynthetic rate and stomatal conductance were lower in the sodium salts and chloride series than in the control. Mineral concentration was lower in sodium salts and chlorides than in control. The nitrate absorption was inhibited in all salts except for NaNO$_3$ and NH$_4$Cl, and specially in NaCl and Na$_2$SO$_4$ treatments of the sodium salts and in KCl treatment of chloride series. K concentration was reduced NaCl and Na$_2$SO$_4$ treatments compared with the other salts. In the sodium salt series, calcium and magnesium concentration were decreased antagonistically when sodium concentration was increased.

• Journal of Bio-Environment Control
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• v.14 no.2
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• pp.119-127
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• 2005

This study was carried out to investigate the effect of magnesium concentrations in fertilizer solution on growth and cut flower quality of chrysanthemum 'Biarritz'. The nutrient concentrations in plant tissue and soil solution of root media were also determined. Magnesium deficiency appeared on older leaves with interveinal yellow-green chlorosis. Marginal chlorosis and necrosis also developed on some of older leaves. Elevation of Mg concentration in fertilizer solution increased cut flower weight at harvesting stage resulting in the 8.84g in 1.5mM treatment. Dry weight of whole above ground plant tissue increased as Mg concentrations in fertilizer solution were elevated within the range from 0 to 15mM, but that of 20mM decreased compared to 15mM treatment. The dry weight of 0.5, 1.0 and 1.5mM treatments were 8.42, 8.75 and 8.848 and tissue Mg contents of those based on the youngest fully expanded leaves at harvesting stage were 0.34, 0.53 and $0.71\%$, respectively. Based on dry weight and tissue Mg contents, Mg fertilization to maintain tissue contents higher than $0.64\%$ is necessary to ensure flower quality and yield. By considering the concentration in 15mM treatment, Mg concentration in soil solution of root media should be higher than $3.68mg{\cdot}L^{-1}$ at harvesting stage.

• Research in Plant Disease
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• v.15 no.1
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• pp.41-45
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• 2009

In order to study a relationship between soil nutrients and rice brown spot occurrence, paddy field soils, rice grains and straws collected from different paddy fields with different disease degrees of brown spots were analyzed for inorganic nutrients. Brown spot was prevalent in the rice grown in nutrient-deficient soils, which is especially low in macronutrient elements (phosphoric acid, potassium, silicic acids) and micronurients (calcium, magnesium). The soil, however, was high in sodium while organic nutrients and pH level were similar to others. The rice straws with severe brown spot were low in inorganics such as ferrous, copper, T-N, and $P_{2}O_{5}$ while the rice grains with brown spot were low in ferrous, MgO, Zn, and Mn. In the analysis of field type and nitrogen level, the highest disease severity was found in sandy-type field soil, followed by salty-type field soil and disease severity decreased as application level of nitrogen fertilizer increased. As a summary, the most important factor for effective brown spot control in rice is maintenance of proper nutrients in sandy-type field and control of sodium level in salty-type field soil.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.4
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• pp.345-350
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• 1997

Characteristics of electrical conductivity(EC) of seventy one-greenhouse soil located in southern part of Korea were surveyed to obtain the basic information for sustainable management of plastic film house soils. The averaged soil EC were 5.84 and 2.49dS/m for top-and sub-soil, respectively, showing distribution of 11.3% for top-soils and 50.7% for sub-soils within the optimum level of 2.0 dS/m. On the whole, the soils with flowering plants revealed higher EC than those with fruiting vegetables showing 2.75~6.34dS/m for the former and 2.29(sub-soils)~5.13dS/m(top-soils) for the latter. In a view of soil sampling time, the soils at Feb., 1996 marked 4.3~37.7% and 10.3(top-soils)~11.3%(sub-soils) higher EC compared with the soils at Sept. and Dec., 1995, respectively. The linear regression correlation coefficients of soil minerals to EC were in oder of $Mg^{2+}$ > $NO_3{^-}$ > $Cl^-$ > $Ca^{2+}$ > $SO_4{^{2-}}$ > $K^+$ for top-soils and were $Cl^-$ > $SO_4{^{2-}}$ > $NO_3{^-}$ > $Ca^{2+}$ > $Mg^{2+}$ > $K^+$ for sub-soils. In especial, the concentration of soil EC accompanied the increasing population ratio of soil fungi to bacteria and/or actinomycetes.

• Journal of Bio-Environment Control
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• v.14 no.2
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• pp.128-136
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• 2005

The objective of this study was to determine the effect of calcium concentrations in fertilizer solution on growth and cut flower quality of chrysanthemum 'Biarritz' To achieve this, deficiency symptom and growth characteristics as influenced by controlled Ca concentrations in fertilizer solution were investigated. The analysis of plant tissue and soil solution of root media were also conducted to secure optimum concentration for plant growth. Calcium deficiency developed on the very youngest leaves and the young leaves developed 'cupped' shape as they expand. The cut flower length of 0, 3.0 and 6.0 mM treatments were 105.8, 106.5, and 107.3cm, respectively. Elevated Ca concentration within the range from 0 to 6.0mM in fertilizer solution increased cut flower weight. The cut flower weight of control and 6.0mM treatment were 51.6 and 59.4 g, respectively. The tissue Ca content of 6.0mM treatment in which crops showed the highest growth among treatments was $3.09\%$ based on the dry weight of the youngest fully expanded leaves. From the results, it seems necessary to maintaining tissue Ca content higher than $2.8\%$. Soil Ca concentrations increased as K concentrations in fertilizer solution were elevated. Ca concentration in 0.0, 1.5, 3.0, 4.5 and 6.0mM treatments were 5.0, 7.4, 12.1, 16.5 and $28.2mg{\cdot}L^{-1}$, respectively, at harvesting stage. It is suggested that Ca concentration higher than $25.4mg{\cdot}L^{-1}$ in soil solution of root media is required to maintain normal growth.