Current Issue 2018. Vol.37, Iss.1

Orginal Articles

• Short-Term Fertilization with Hairy Vetch, Compost and Chemical Fertilizer Affect Red Pepper Yield and Quality and Soil Properties

  Gopal Selvakumar, Pyoung Ho Yi, Seong Eun Lee, Seung Gab Han / Korean Journal of Environmental Agriculture / 2018 / v.37, no.1, 9-14

  https://doi.org/10.5338/KJEA.2018.37.1.10

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  The use of green manure and compost as organic fertilizer may increase crop yield and soil fertility due to improved soil nutrient availability and soil organic matter content (SOM). This study aimed to investigate the effects of hairy vetch (Vicia villosa L.) and compost application on red pepper growth, yield, fruit quality and soil health.

  METHODS AND RESULTS:

  The treatments were no fertilizer (CON), chemical fertilizer (CF), hairy vetch (HV), and livestock compost+HV (LC+HV). Red pepper seedlings (70 days old) were transplanted and maintained in experimental plots for 140 days. Plant dry weight, microand macronutrient contents of plants and soil chemical properties were determined. All fertilizer treatments significantly increased plant dry weight. Fruit yield was significantly highest with HV treatment. As for nutrient content, plants in HV and LC+HV treatments have significantly higher K and Ca contents than the other treatments. Regarding soil properties, HV and LC+HV application significantly altered the soil chemical properties. Significantly higher SOM was observed in HV and LC+HV treated soils.

  CONCLUSION:

  The results of this study suggest that short-term application of hairy vetch and compost is an effective alternative to the conventional chemical fertilizer to increase fruit yield red pepper and improve soil health.

• Elevated Temperature Treatment Induced Rice Growth and Changes of Carbon Content in Paddy Water and Soil

  Sung-Chang Hong, Seung-Oh Hur, Soon-Kun Choi, Dong-Ho Choi, Eun-Suk Jang / Korean Journal of Environmental Agriculture / 2018 / v.37, no.1, 15-20

  https://doi.org/10.5338/KJEA.2018.37.1.01

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  The global mean surface temperature change for the period of 2016∼2035 relative to 1986~2005 is similar for the four representative concentration pathway (RCP)’s and will likely be in the range of 0.3℃ to 0.7℃. Climate change inducing higher temperature could affect not only crop growth and yield, but also dynamics of carbon in paddy field.

  METHODS AND RESULTS:

  This study was conducted to evaluate the effect of elevated temperature on the carbon dynamics in paddy soil and rice growth. In order to control the elevated temperatures, the experiments were set up as the small scale rectangular open top chambers (OTCs) of 1 m (width)×1 m (depth)×1 m (height) (Type 1), 1 m (W)×1 m (D)×1.2 m (H) (Type 2), and 1 m (W)×1 m (D)×1.4 m (H) (Type 3). The average temperatures of Type 1, Type 2, and Type 3 from July 15 to October 30 were higher than the ambient temperatures at 0.4℃, 0.5℃, and 0.9℃, respectively. For the experiment, Wagner’s pots (1/2,000 area) were placed inside chambers. The pots were filled with loamy soil, and chemical fertilizer and organic compost were applied as recommended after soil test. The pots were flooded with agricultural water and rice (Shindongjin-byeo) was planted. It was observed that TOC (total organic carbon) of the water increased by the elevated temperatures and the trend continued until the late growth stage of the rice. Soil TOC contents were reduced by the elevated temperatures. C/N ratios of the rice plant decreased by the elevated temperature treatments. Thus, it was assumed that the elevated temperatures induced to decompose soil organic matter. Elevated temperatures significantly increased the culm length (P<0.01) and culm weight (P<0.05) of rice, but the number and weight of rice panicle did not showed significant differences.

  CONCLUSION:

  Based on the results, it was suggested that the elevated temperatures had an effect on changes of soil and water carbons under the possible future climate change environment.

• Measurement of Exchangeable Cations in Salt Accumulated Vinyl Greenhouse Soils

  Jong-Bae Chung, Yong-Se Lee, Byeong-Ryong Jeong / Korean Journal of Environmental Agriculture / 2018 / v.37, no.1, 21-27

  https://doi.org/10.5338/KJEA.2018.37.1.04

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  Although 1 M NH₄OAc (pH 7.0) is predominantly used as the extractant of exchangeable cations in agricultural soils, this method is unsuitable for extracting the cations in saline and calcareous soils. This study was performed to select a proper method to determine exchangeable cations in vinyl greenhouse soils.

  METHODS AND RESULTS:

  Exchangeable cations (Ca, Mg, K, Na) in saline vinyl greenhouse soils were determined after extraction with 1 M NH₄OAc (pH 7.0 and 8.5) and 1 M alcoholic NH₄Cl (pH 8.5). Sum of exchangeable cations of the soils extracted with 1 M NH₄OAc at pH 7.0 was 1.9-2.5 times greater than soil cation exchange capaity determined at pH 7.0, even though soluble salts were pre-removed. A similar result was found when the cations were extracted with 1 M NH₄OAc at pH 8.5. Those results are mostly due to the overestimation of exchangeable Ca and Mg, linked to a partial dissolution of sparingly soluble salts in NH₄OAc solution. When extracted with 1 M alcoholic NH₄Cl at pH 8.5, extractable Ca and Mg decreased significantly due to the lower solubility of Ca and Mg carbonates in the extractant. And the sum of exchangeable cations was very close to the corresponding exchange capacity of soils.

  CONCLUSION:

  Alcoholic NH₄Cl (pH 8.5) is proposed as a reliable extractant in determination of exchangeable cations in saline vinyl greenhouse soils. And soluble salts should be removed prior to the extraction of exchangeable cations.

• Effects of Incorporation of Green Manure Crops on the Growth of Watermelonand Soil Nitrate Nitrogen Concentration

  Tae-Jun Lim, Jin-Myeon Park, Seong-Eun Le / Korean Journal of Environmental Agriculture / 2018 / v.37, no.1, 28-33

  https://doi.org/10.5338/KJEA.2018.37.1.06

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  In this study, we evaluated the effects of soil incorporation of hairy vetch (HV) or ryeas a green manure on the growth and yields of watermelon and soil nitrate nitrogen in a green house.

  METHODS AND RESULTS:

  HV and rye were cultivated for 151 days after sowing on October 30th and incorporated into soil before transplanting watermelon. The amount of N added by soil incorporation of HV and rye were 79 kg/ha and 88 kg/ha, respectively. Five different N treatments for each of HV and rye were included as follows: green manure, green manure with urea at 25%, 50%or 75%, and 100% ureafor the N recommendation rate. The growth and fruit yield of watermelon were not different among the treatments of both HV and rye. Soil nitrate N content at both HV and rye treatments decreased continuously with the lapse of days after planting (DAP) and was lowest at 75 DAP: 44 mg/kg and 52 mg/kg the for the HV and rye treatment without urea, respectively.

  CONCLUSION:

  These results indicate that the N mineralized from the soil incorporated HV or rye accounts for an important portion of N available for the growth and fruit yield of watermelon. It can be suggested that the green manures, comparable to ureacould ensure the yield of watermelon, if soil nitrate N content isabove 40 mg/kg by soil incorporation of HV and rye during watermelon cultivation. However, further studies on the relationship between soil nitrate N content during cultivation periods and the fruit yield of watermelon are required.

• In vitro Antifungal Activities of Fungicides against Japanese Plum Fruit Anthracnose Fungi

  Byeong-Ryong Jeong, Tae-Yi Lee, Min-Jung Park, Da-Hee Ha, Jong-Bae Chung, Yong-Se Lee / Korean Journal of Environmental Agriculture / 2018 / v.37, no.1, 34-40

  https://doi.org/10.5338/KJEA.2018.37.1.03

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  In order to select a fungicide that can effectively control anthracnose disease in Japanese plum fruit, mycelial growth inhibition effect and spore germination inhibition effect of six fungicides were tested in vitro against six isolates of Colletotrichum acutatum and five isolates of C. gloeosporioides that were isolated from diseased Japanese plum fruit.

  METHODS AND RESULTS:

  Inhibitory effects of fungicides on mycelial growth were investigated after inoculating each isolate on potato dextrose agar amended with four discriminatory concentrations of each fungicide for 7 days at 25℃. For spore germination inhibitory effect, each isolate of the Colletotrichum spp. was cultured in potato dextrose agar for 7-14 days at 25℃. After adjusting the concentration of spores of each isolate to 1×10⁶ mL^-1 by diluting with 0.025% PDB, the spore suspension was mixed with each fungicide (1:4, v/v), and 60 μL aliquots were dispensed to sterile hole slide glass. Hole slide glasses were placed in a humidified box and incubated for 15 hours at 25℃. Then, spore germination was observed under an optical microscope. At recommended concentration of fungicide prochloraz manganese showed the highest mycelial growth inhibitory effect and dithianon showed the lowest mycelial growth inhibition. The EC₅₀ values for the inhibition of spore germination by dithianon and pyraclostrobin were 0.069-0.126 μg/mL and 0.37-1.59 μ g/mL, respectively. Although benomyl, prochloraz manganese, azoxystrobin, and tebuconazole did not inhibit the spore germination, they appeared to restrain mycelial growth by abnormal growth of germ tube and mycelium after germination.

  CONCLUSION:

  Dithianon seemed to have preventive effect. Prochloraz manganese, azoxystrobin, and tebuconazole were likely to have control effect. Pyraclostrobin is considered to have both preventive and control effect against anthracnose disease of Japanese plum fruit.

• Residue Dissipation Behavior of Bistrifluron and Cyenopyrafen in Peach for the Cultivation Periods under Field Conditions

  Eun-Jin Hwang, Jung-Eun Park, Chan-Hyeok Kwon, Jin-Sook Kim, Hee-Ra Chang / Korean Journal of Environmental Agriculture / 2018 / v.37, no.1, 41-48

  https://doi.org/10.5338/KJEA.2018.37.1.07

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  This study was performed to calculate the biological half-lives and regression coefficient of bistrifluron and cyenopyrafen dissipation in peach and to estimate the Pre-Harvest Residue Limits (PHRLs).

  METHODS AND RESULTS:

  The bistrifluron and cyenopyrafen were prepared on the basis of good agricultural practice for peach and treated with a single application. Peaches were harvested at 0, 1, 3, 5, 7, 10 and 14 days after application, prepared for analysis, and analyzed by HPLC-DAD. The limits of quantitation (LOQ) of bistifluron and cyenopyrafen were 0.02 mg/kg and 0.04 mg/kg, respectively. The recoveries of bistrifluron and cyenopyrafen were 99.5~108.7% and 88.4~98.9% at two different concentration levels. The biological half-lives of field I (Sejong) and field II (Pyeongtaek) were 6.1 and 7.0 days for bistifluron, and 6.3 and 7.0 days for cyenopyrafen, respectively. The 95% confidence intervals of dissipation rate constants of bistrifluron in peach were 0.0805∼0.1457 and 0.0577∼0.1417 for field I and field II, respectively, and those of cyenopyrafen were 0.0911∼0.1278 and 0.0576∼0.1417, respectively.

  CONCLUSION:

  Residue dissipation of bistrifluron and cyenopyrafen in peach were similar to that of correction to sample weight difference during the harvest periods. This study suggests that residue dissipation rate would be helpful to set the PHRLs that protect public health.

• Removal Efficiency of Ammonia and Toluene using Mobile Scrubber

  Jae-Young Kim, Jang-Yoon Kim, Yeon Hee Lee, Min Sun Kim, Min-Su Kim, Hyun Ji Kim, Tae In Ryu, Jae Hyeong Jeong, Seung-Ryul Hwang, Kyun Kim, Jin Hwan Lee / Korean Journal of Environmental Agriculture / 2018 / v.37, no.1, 49-56

  https://doi.org/10.5338/KJEA.2018.37.1.02

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  The mobile vortex wet scrubber was developed to remove the harmful chemicals from accidental releases. However, there was a disadvantage that it was limitedly used for volatile organic compounds (VOCs) such as toluene according to the physicochemical properties. This study compared the removal efficiencies of an improved mobile scrubber on toluene and ammonia by applying diverse adsorption and absorption methods.

  METHODS AND RESULTS:

  The removal efficiencies on harmful chemicals were examined using various adsorption and absorption methods of water vortex process (C), phosphoric acid-impregnated activated carbon adsorption(PCA), pH-controlled water (pH 2.5) vortex process absorption with sulfuric acid (SWA) after ammonia exposure, granular activated carbon adsorption (GCA), and activated carbon mat adsorption (CMA) after toluene exposure. As a result, the best removal efficiency was shown in the SWA for ammonia and GCA for toluene. Also, the SWA and GCA methods were compared with different concentration levels. In the case of ammonia exposure (5, 10 and 25%), there was no difference by concentration levels, and the concentration in the outlet gradually increased, with pH change from acid to base. In the case of toluene exposure (50, 75 and 100%), the outlet concentration was higher relative to the exposure concentration in the initial 10 min, but the outlet concentration was remained steady after 10 min.

  CONCLUSION:

  The newly improved mobile scrubber was also effective in removing VOCs through adsorption techniques (activated carbon, activated carbon fiber, carbon mat filter etc.), as well as removing acid-base harmful chemicals by neutralization reaction.

• Analytical Method for Flusulfamide as Benzenesulfonamide Fungicide, Residues in Major Agricultural Commodities

  Kyung-Geun Ahn, Gi-Ppeum Kim, Young-Sun Hwang, In-Kyu Kang, Young Deuk Lee, Myoung-Gun Choung / Korean Journal of Environmental Agriculture / 2018 / v.37, no.1, 57-65

  https://doi.org/10.5338/KJEA.2018.37.1.05

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  An analytical method was developed using HPLC-UVD/MS to precisely determine the residue of flusulfamide, a benzenesulfonamide fungicide used to inhibit spore germination.

  METHODS AND RESULTS:

  Flusulfamide residue was extracted with acetone from representative samples of five raw products which comprised apple, green pepper, Kimchi cabbage, hulled rice, and soybean. The extract was diluted with large volume of saline water and directly partitioned into dichloromethane to remove polar co-extractives in the aqueous phase. For the hulled rice and soybean samples, n-hexane/acetonitrile partition was additionally employed to remove non-polar lipids. The extract was finally purified by optimized Florisil column chromatography. On an octadecylsilyl column in HPLC, flusulfamide was successfully separated from co-extractives of sample, and sensitively quantitated by ultraviolet absorption at 280 nm with no interference. Accuracy and precision of the proposed method was validated by the recovery experiment on every crop sample fortified with flusulfamide at 3 concentration levels per crop in each triplication.

  CONCLUSION:

  Mean recoveries ranged from 82.3 to 98.2% in five representative agricultural commodities. The coefficients of variation were all less than 10%, irrespective of sample types and fortification levels. Limit of quantitation (LOQ) of flusulfamide was 0.02 mg/kg as verified by the recovery experiment. A confirmatory method using LC/MS with selected-ion monitoring technique was also provided to clearly identify the suspected residue.

• Effect of Phosphorus Removal by Oyster Shell on Longevity of Constructed Wetlands

  Seong-Heon Kim, Hong-Chul Kim, Jong-Hwan Park, Seong-Ki Ryu, Se-Won Kang, Ju-Sik Cho, Dong-Cheol Seo / Korean Journal of Environmental Agriculture / 2018 / v.37, no.1, 66-72

  https://doi.org/10.5338/KJEA.2018.37.1.08

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  Constructed wetlands are low-cost alternatives for treating domestics sewage. However, previous study has reported that the removal of phosphorus in constructed wetlands was limited. Therefore, a new alternative was needed to extend the life of the constructed wetlands. The purpose of this study was to evaluate the effect of total phosphorus removal by oyster shell on longevity of constructed wetlands for treating domestic sewage.

  METHODS AND RESULTS:

  The changes of total phosphorus concentration and treatment efficiency in two constructed wetlands (CWs) classified as system A (coarse sand 100%) and system B (coarse sand 90%+oyster shell 10%) were investigated for 6 years. The actual saturation time of total phosphorus in the systems A and B was estimated to be longer than that of theoretical saturation by adsorption isotherm experiment. In particular, the saturation pattern of phosphorus in system A was maintained at a certain concentration level in the initial stage of operation, and finally saturation was reached as the saturation gradually progressed from the breaking point. In system B, the saturation period of phosphorus was prolonged as compared with system A due to the addition of oyster shells.

  CONCLUSION:

  Our results suggest that the longevity of the constructed wetlands can be extended due to the phosphorus saturation by adding the oyster shells to the coarse sands in constructed wetlands.