• Korean Journal of Soil Science and Fertilizer
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• v.49 no.5
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• pp.409-419
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• 2016

With increasing social concerns for healthy food, the studies on the cultivation of crops to increase accumulation of functional metabolites in crops have been investigated. Accumulation of the metabolites in crops is highly affected by various types of stress, such as nutrient deficiency, water deficit (WD), extreme temperature and UV-B radiation as well as their own life cycle. This review summarizes the previous studies on the effects of environmental stresses, especially WD and UV-B radiation, on accumulation of functional metabolites in crops. UV-B radiation and WD during specific period (mainly at maturation stage) activates the adaptation and/or defense system in crops, thereby increasing biosynthesis of the metabolites. Although WD and UV-B radiation tend to decrease in crop yield, the decrease can be compensated by the production of high value crops having high content of functional metabolites.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.474-481
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• 2013

Understanding the microbial community structure of agricultural soils is important for better soil management in order to improve soil quality. Phospholipid fatty acid analysis has been popularly used in determining the microbial community structure in different ecosystems. The microbial community structure of paddy soil under long-term fertilizer treatments was investigated after 45 years using PLFA analysis. Treatments were control (no fertilization, Con), compost (COM), NPK, NPK+compost (NPKC), PK, NK, and NP. Soil chemical properties were mainly affected by the addition of compost and inorganic P fertilizer. Total nitrogen and organic matter contents were significantly higher in treatments with compost while available $P_2O_5$ and exchangeable calcium were significantly higher in treatments with added inorganic P fertilizer. It was found that microbial communities were responsive to the different fertilizer treatments. PLFA results showed that the soils were dominated by gram-negative bacteria, followed by the actinomycetes, then gram-positive bacteria, and fungi. Principal component analysis of the soil chemical properties and PLFA composition proved to be a more reliable tool because it was more responsive to the changes in soil chemical properties.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1314-1319
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• 2011

This study was carried out to investigate the surface soil organic carbon fractions affecting by different land use types, including needle-leaf forest (FN), broad-leaf forest (FB), pasture, annual upland cropping land (upland), and paddy rice land (paddy). We chose seven regions across Korean inland, considering sea level altitude, and measured soil organic carbon content and physico-chemical properties such as bulk density at a depth of 0~15 cm using core samples in April for the each land use type. In addition, labile organic carbon fractions in soil including light fraction and hot water extractable carbon were investigated. From this study, organic carbon storage (Mg C per ha) in the upper 15-cm soils was highest in FB (37.8), and decreased in the order of pasture (29.1), FN (28.8), paddy (21.9), and upland crop (19.9). In forest, more than 20% of soil organic carbon existed as light fraction, the free organic matter. Hot-water extractable carbon contents of soils in five land use types were lower than 7% of their soil organic carbon content.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.6
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• pp.648-657
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• 2015

Soil organic matter (SOM) plays an important role in the continuous production and environmental conservation in arable soils. In particular, the decomposition of organic matter in soil might promote soil organic matter and fertility due to the mineralization of N. In this study, to evaluate the effect of organic matter amendment on the C mineralization and N dynamic, $CO_2-C$ flux, extractable N and $N_2O$ emission were determined using closed chamber for 4 weeks at 10, 15, $20^{\circ}C$ of incubation temperature after the mixture of $2Mgha^{-1}$ rice straw compost and rye in sandy loam and clay loam. Regardless of soil texture, decomposition rates of rice straw compost and rye at $10{\sim}20^{\circ}C$ of incubation temperature ranged from 0.9 to 3.8% and 8.8 to 20.3%, respectively. Rye application in soil increased $NH_4-N$ and $NO_3-N$ content as well as the $N_2O$ emission compared to the rice straw compost. After incubation for 4 weeks, total C content in two soils was higher in rice straw compost than in rye application. In conclusion, application of rice straw compost and rye to soil was able to improve the soil organic matter and fertility. However, organic matter including the recalcitrant compounds like rice straw compost would be effective on the management of soil organic matter and the reduction of greenhouse gases in soil.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.4
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• pp.312-317
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• 2015

This study was conducted to evaluate effects of diethylene triamine penta acetic acid (DTPA) treatment on growth of red pepper and nutrient availability to salt accumulated soil in the plastic film house. The treatments were no application (Control), chemical fertilizers (NPK), DTPA (0.06, 0.13, and 0.19 mM) and the half of chemical fertilizers (NPK) with DTPA 0.06 mM. Fruit yield of red pepper showed no significant difference between the treatments (control, NPK, DTPA 0.06 mM, 0.13 mM, except for DTPA 0.19 mM. Red peppers were killed by DTPA 0.19 mM treatment because the high concentration of DTPA was toxic to crop. However, dry mass (stem and leave) and nutrient uptake of red pepper in DTPA 0.06 mM treatment increased significantly compared with those of control. In particular, nutrient uptake of red pepper in DTPA 0.06 mM treatment increased in the order of Fe, Mn, and Zn > Ca and Mg > K, as the magnitude of the stability constants of DTPA. Thus the application of DTPA 0.06 mM was the most effective for the alleviation of nutrient accumulation in the plastic film house soils.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.417-425
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• 2013

This study investigated the runoff from rice paddy located on reclaimed fine sandy loam soil to provide data for the development of policies to protect water quality of estuaries. Total N (TN), Total P (TP) concentrations and runoff loads at outlet were monitored from 2006 to 2008. Soil phosphate adsorptivity was measured and compared with typical paddy soil in watersheds. TP concentration of the paddy water and TP runoff loads were much greater than those of typical paddy field in watershed because phosphate adsoptivity in reclaimed paddy field of fine sandy loam appeared to be a third of those of typical paddy soils by relatively low soil OM and high sand content of the reclaimed soil. Thus, nutrient runoff, particularly phosphate from the reclaimed paddy field needs to be managed more thoroughly to protect estuarine water quality.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.2
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• pp.194-199
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• 2016

In an experiment conducted at the research field of the National Institute of Agricultural Science, we investigated the effects of mineral fertilizer and rice straw compost on exchangeable potassium and K balances, and rice grain yield under a rice single system. The treatments were no fertilization (No fert.), inorganic fertilization (N), inorganic fertilizer (N, P, K) plus rice straw compost at rates of 7.5, 15.0, 22.5, and $30.0ton\;ha^{-1}$ (NPKC7.5, NPKC15.0, NPKC22.5, and NPKC30.0, respectively). The inorganic fertilizers(N, P, K) were added with standard fertilizer application rate in which nitrogen (N), phosphate ($P_2O_5$), and potassium ($K_2O$) were applied with $75{\sim}150kg\;ha^{-1}$, $70{\sim}86kg\;ha^{-1}$, $75{\sim}86kg\;ha^{-1}$, respectively. Exchangeable potassium for NPKC15.0 NPKC22.5, and NPK30.0 treatments was higher by $0.05{\sim}0.19cmol_c\;kg^{-1}$ than that of NPKC7.5 treatment. Increasing levels of rice straw compost resulted in an increase in the K balance from - $19.9kg\;ha^{-1}yr^{-1}$ (No fert.) to $41.9kg\;ha^{-1}yr^{-1}$ at NPKC22.5 treatment and $62.9kg\;ha^{-1}$ at NPKC30.0 treatment. Continuous application of rice straw compost with NPK fertilizers affected significantly the rice grain yields. The result of the study imply that the application of more than $22.5ton\;ha^{-1}$ of rice straw compost with NPK fertilizers are recommended as the best fertilization practice for enhancement of crop production and K supplying power of soil in the continuous rice cropping system.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.464-468
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• 2015

Our government has performed to support the nation-wide application of customized fertilizer based on soil-testing results and crop nutrient balance in order to promote the environment-friendly agriculture and to respond the global environment guide-line since 2010. This study was performed at the selected local paddy fields (Hwaseong-si, Uiseong-gun and Miryang-si) with different soil chemical properties in 2012. The contents of amino acids measured showed an increasing trend with fertilization, and glutamic acid was the most abundant amino acid followed by aspartic acid, leucine and alanine. However, valine, isoleusine, tyrosine and lysine were not significantly affected by fertilization. The significant differences in grain N, expressed as a crude protein, and amino acids dose was observed between experimental sites (p<0.001), treatments (p<0.01 to 0.001) and interaction of both factors (p<0.01 to 0.001). In our experiment the following order of carbon skeleton backbones to produce amino acids was observed irrespective of experiment sites and fertilization: ${\alpha}$-ketoglutarate > oxalate > pyruvate > 3-phosphoglycerate > phosphoenolpyruvate. In conclusion, customized fertilizer had no difference in amino acids compared to the conventional-NPK practice which was higher than in no fertilization, and also the normal paddy represented slightly higher amino acids compared to the reclaimed. Further study based on the present results is required to investigate what is main factor to amino acids between genetic and environmental factors.

• Weed & Turfgrass Science
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• v.3 no.3
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• pp.240-245
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• 2014

This study was carried out to determine the possible use of volcano eruption sand at Merapi mountain area compared with clayey soil, alfisol as turfgrass growing media. Indonesia has abundant source of eruption sand and clayey soil. Native zoysiagrass (Z. matrella) was collected from Sleman district and seashore paspalum (P. vaginatum) from Solo region. The experimental plots were treated with both organic and inorganic fertilizers. Zoysiagrass and seashore paspalum can grow on the mixture of eruption volcano sand and alfisol soil. Fertilizers application increased turf color, surface coverage rate and recovery rate of turfgrass. While fertilizer treated alfisol have no effect on the length and dry weight of zoysiagrass root. Mixing of volcano eruption sand on growing media resulted in longer root length, higher shoot dry weight of zoysiagrass than in alfisol soil. Type of fertilizer affected the pH, soil organic matter, total N, available P, available K and electrical conductivity of sand and alfisol after cultivation. Similarly to zoysiagrass, the recovery of seashore paspalum was increased by application of fertilizer, even the inorganic fertilizer showed faster recovery than organic fertilizer. Surface coverage of seashore paspalum was faster than that of zoysiagrass with or without fertilizer.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1009-1016
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• 2012

The purpose of this study was to determine the effects of organic fertilizers on soil properties and growth and quality of melon. Organic fertilizer was applied in soil at the rate of 0, 0.5, 1, 2N according to Rural Development Administration guideline in Korea. The fertilizer had no effects on plant growth-rate parameters, including plant height, leaf number, and leaf size. There were minor effects on the fruit quality parameters such as fruit weight, fruit length, fruit width, placenta and seed weights, sugar content, and starch content. Ascorbic acid level was decreased as fertilizer level was increased. The level of nitrate in groundwater increased with increased levels of N.