• Korean Journal of Soil Science and Fertilizer
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• v.51 no.1
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• pp.71-78
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• 2018

This study was conducted to investigate the application effect of liquid fertilizer using pig cadavers on potato and corn cultivations in upland field. Field experiments were designed with control (Cn), liquid fertilizer (LF), inorganic fertilizer (IF), and LF + IF treatments. Crop yields in potato and corn cultivations were higher in the order of $LF+I{\geq_-}IF{\geq_-}LF$ > Cn treatments. The potato and corn yields in LF + IF treatment were 237% and 29% greater than those in Cn treatment, respectively. Following crops harvest, soil status was improved, showing greater soil chemical properties in the LF treated areas compared to those in the Cn treatment. In addition, total $CO_2$ fluxes in LF + IF treatment during potato and corn cultivations were significantly increased compared with Cn and IF treatments. Therefore, these results suggest that LF application was effective on crop cultivation and improvement of soil fertility.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.1
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• pp.73-78
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• 1983

In order to investigate the relation between weather factors, soil water, and tobacco yield grown by nonnulching and mulehing cultivations, a regression analysis was conducted for data collected from 8 years (1971 to 1978) for a flue-cured variety of Hicks. The soil water was calculated by Smith's method. 1 . Tobacco yield was largely correlated to soil water deficit during draught time for nonmulclung cultivation; $Y=6.146+8.6185\times-0.0925$\times2(R=0.935)^{***})$ 2. Tobacco yield was more largely correlated to soil water in flexible draght time interval than in fixed time interval during maximum growing phase.3. This field test was supposed that the optimal soil water condition was 65%field caps city. In this condition tobacco yield was 197. 1-216.5kg/10a for non-mulching cultivation. But the soil water deficit in draught season was little matter for mulching cultivation. The relation between xield and evaporation during May to June was Y: -1199.55+9.4 353$\times$:O. 0155$\times$2 (R=0.904") Maximum tobacco yield was expected to 223.6-251.4kg/10a for mulching cultivation. 5 . Tobacco required high temperature and light even in drying season (maximum growing phase) for mulching cultivation.tion.

• Korean Journal of Organic Agriculture
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• v.19 no.2
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• pp.229-243
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• 2011

Consumers' interest and government's support for the fruits rapidly increased organic fruit productions. This study was examined to compare the soil physicochemical and microbial properties of orchards soil in conventionally and organically management systems. Organic cultivation had lower soil bulk density, solid phase, and penetration resistance than the conventional cultivation. Soil pH and organic matter contents increased from March to August, and the values were greater in the organic cultivation than the conventional cultivation. Total nitrogen (N) and phosphorous concentrations decreased from March to August, and the organic soils had greater N but lower phosphorous concentrations than the conventional soils. Soil microbial carbon biomass increased 36% and 15% for organic and conventional cultivations, respectively, from March to August. Soil microbial N biomass was greater in June than March or August, and the organic cultivation had a greater biomass N compared to the conventional cultivation. Soil dehydrogenase and chitinase activities were greater in June than in March or August. ${\beta}$-glucosidase activity declined in both cultivations, while the phosphatase activity increased. Organic cultivation had greater enzyme activities in March, June, and August, except for the acid phosphatase activity in June.

• International Journal of Advanced Culture Technology
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• v.8 no.1
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• pp.182-187
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• 2020

Silver nanoparticles (AgNPs) have been manufactured in recent years and widely used in various fields. Reactive oxygen species (ROS), which occur in AgNPs, destroy cell membranes. It is widely accepted that ROS generated in this manner inhibit microorganisms growth and causes toxic effects, However, it does not affect cell membranes directly but positively affects growth in plants with cell walls. The nanoball used in this experiment is a new material that generates ROS stably and is used in aqueous solution. Results of this study indicate a 30% increase in yield of Ginseng mixed with culture soil. The analysis of soil condition after cultivation showed that the possibility of repetitive cultivation in soil mixed with Nanoball was high. This suggests that Nanoball is an antimicrobial active material due to the microbial / extermination effect of pathogenic microorganisms. Therefore, there may be potential applications in agricultural cultivation sites as a repetitive cultivation technology that reuses soil.

• Korean Journal of Weed Science
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• v.17 no.1
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• pp.73-79
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• 1997

Governments and industry have a growing interest in the harmonization of environmental test methods and risk assessment procedures. OECD are currently producing a set of harmonised test guidelines for studying the environmental fate and ecological effects of pesticides. FAO has published an environmental risk assessment procedure. This procedure, which is similar to those used in US and Europe, is based on calculating the ratio of the toxicity of a pesticide to indicator organisms to their level of exposure to the pesticide. The exposure depends on both the concentration of the pesticide and its bioavailability. Ratios which indicate a pesticide will not produce a harmful effect have been established using ecological field studies. Examples are presented for assessing the risk to aquatic ecosystems, earthworms and honeybees. Long-term field studies(up to 20 years) have also shown that pesticides can be used indefinitely without harming soil fertility. Herbicides can be used to avoid the ecologically damaging effects of using soil cultivations excessively for weed control.

• Korean Journal of Soil Science and Fertilizer
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• v.51 no.1
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• pp.61-70
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• 2018

This study was carried out to review and compare crop cultivations upon chemical properties of paddy soil and qualitative characteristics of rice in Sejong-city from a point of view of farming extension to rice farmers and to utilize the result of the study as a basic guideline for precise agricultural practice. The pH in soils of Sejong was about 6.1-6.6 and had no difference with an average pH of paddy soils in Chung-Nam with pH 6.1. However, the average of organic matter, calcium (Ca) and available silicate in Sejong was lower than the average of them in Chung-Nam. The yields of rice were higher in 2010 than in 2011 and 2012, and the protein contents of rice were the highest in 2011 while the lowest water contents of rice in 2011. The protein contents upon regions were the highest in 2011 with 6.1%, and the amylose contents were the highest in Yeondong-myun, Jeoneu-myun, and Yeonseo-myun in 2010 while Kumnam-myun and Jeondong-myun were the highest in 2012. With the increase of precipitation, the protein content level in rice was increased while the amylose content level tended to decrease. Correlations between the chemical properties of paddy soil and the quality of rice and between level of organic matter in soil and amylose contents were negative (r = -0.507), and the correlation between the moisture contents and amylose contents (r = 0.419) and between the water contents and whiteness (r = 0.485) were positive. Because the quantity and quality of rice yield is determined by the soil characteristics, the consultation to farmers for the proactive soil analysis and for the maintenance of stable level of pH, organic matter and available silicate based on historical results of analysis is highly recommended. Also, the analysis on the effect of the weather and the soil characteristics affecting the quality and quantity of rice would be another good way.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.579-584
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• 2001

This experiment was conducted to investigate the effect of soil moisture content on cut flower quality of Gypsophila paniculata L. 'Bristol Fairy' in spring and autumn cultivations. The soil moisture potential (SMP) set point for irrigation was either -3.2 or -10.0kPa in the vegetative growth stage, and -10.0, -31.6, or -79.4kPa after the budding stage. When soil moisture reached at each set SMP point, 10 mm water was drip-irrigated. Tendency of flowering was earlier as SMP set point was lower in both vegetative growth and after budding stages. No other flower characteristics were found among other treatments. In both spring and autumn cultivations, as SMP set point was lower, the low primary branch length and upper internode length were decreased, the stem firmness was increased, and curvature of cut flower stem was decreased. Especially, in autumn, the higher the SMP set point, the higher the low primary branch than the apex, thus the paniculate inflorescence was deeply destroyed. Yield in spring cultivation was not significantly different among treatments, while that in autumn cultivation increased as the lower the SMP value. It is thought that optimal imgation points during vegetative growth and after budding stages to produce high quality cut flowers are -10.0 and -79.4kPa, respectively.

• Weed & Turfgrass Science
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• v.2 no.4
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• pp.381-386
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• 2013

Recent climatic changes by global warming include increased amount and intensity of rainfall. This study was conducted to find out possible roles of turfgrasses to reduce the impact of climatic changes, especially surface soil erosion. Soil erosions by intensive rain were measured after each significant precipitation from the artificially sloped plots of zoysiagrass, cool-season grass mixture of Kentucky bluegrass and perennial ryegrass and other typical korean summer crops. Sodded zoysiagrass resulted in minimal annual soil erosion followed by strip-sodded zoysiagrass and cool-season turfgrass mixture while dry-field rice and bean cultivations eroded the surface soils of 5 to 10 MT $ha^{-1}yr^{-1}$ and pepper cultivation resulted in 7 to 14 MT $ha^{-1}yr^{-1}$ annual loss of surface soil. Annual loss of surface soil from bare land with hand weeding was up to 18 MT $ha^{-1}yr^{-1}$ while greatly reduced soil erosion was observed from weed grown treatment.

• Korean Journal of Organic Agriculture
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• v.23 no.2
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• pp.281-289
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• 2015

In sustainable viticulture, green manure represents a safe and non-polluting way to bring large quantities of organic matter into the soil. The cultivation of green manure crops plays an important role in soil quality and sustainability of agricultural system. This study was conducted to evaluate the effects of green manure fertilization on yield and quality of the Campbell Early grape variety in the organic vineyard. Hairy vetch was the more productive green manure crop, yielding higher dry materials. Average yields of grape were significantly greater in hairy vetch+rye ($13.02ton\;ha^{-1}$) than nature weed ($11.65ton\;ha^{-1}$), respectively. The concentrations of total as well as individual anthocyanins were consistently higher with hairy vetch treatment compared with rye and nature weed, thus making the green manure cultivation is an environmentally friendly cultivation to increase the yield and anthocyanin contents in organic grape.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.195-195
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• 2017

The water in the crop cultivation shows difference according to the variety of crop, cultivations period and climatic condition. The growth and development, quantity and fruit enlargements are affected by soil water conditions. In previous study, leaf area and photosynthesis are decreased by lower soil moisture. Other research reported that excess moisture condition at vegetative and reproductive growth period in cultivation of soybean caused highest reduction in crop growth rate (CGR) and dry weights of plant parts. In particular, the damage was bigger during vegetative growth stage than reproductive growth period. Soybean (Glycine max (L.) Merill) is useful and popular crop throughout the world. It is very popular crop in Korea, China, Japan and other Asian countries. Soybeans used in various way including soybean sprouts, paste, soymilk, oil and tofu. Two soybean cultivars grown in four different irrigation conditions were determined for physiological responses. In this study, we examined leaf area (LA), leaf dry weight (LDW), specific leaf area (SLA), root dry weight (RDW) and shoot height (SH) in different water conditions. 50mL/9day irrigation periods showed the lowest contents in LA, LDW, RDW, SH. Water deficit caused increase of leaf Water saturation deficits (WSD), Cheongjakong 3 and Taekwangkong showed increase of leaf water saturation deficits (WSD) in drought conditions and leaf water potential and stomatal conductance were decreased. Photochemical efficiency was decreased in 50mL/1day irrigation condition while, there was decrease of growth and development in 50mL/9day with drought.