• Weed & Turfgrass Science
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• v.5 no.4
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• pp.213-218
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• 2016

Timely application and the choice of herbicides are crucial for red pepper production since the yield is significantly reduced by weed occurrence. Experiments were conducted to provide efficient weed control methods in red-pepper fields. The results suggest the followings: 1) in the field of prevalent grass weeds, application of pendimethalin EC as pre-emergence herbicide after transplanting followed by tank-mix with pendimethalin and fluazipfop-P-butyl EC as post-emergence at 3-5 leaf stage of Digitalia species gave a good control for 80 days without crop injury, 2) as for grass and other weeds occurrence, sequential application of tank-mix with glufosinate-ammonium SL and pendimethalin at 30 days after transplanting (DAT) followed by glufosinate-ammonium. at < 20 cm of weed height with 30 days' interval provided better weed control than 2-time application of glufosinate-ammonium. single application for 80 days in this trial. 3) To prevent from drifting of non-selective herbicide spray mist into red-pepper at furrow application, glufosinate-ammonium. should be applied at 15 cm of spray nozzle height at 20 DAT (18 cm tall of red pepper), and the spray nozzle should be placed below 30 cm above ground to keep spray drift minimum to red pepper with > 40 cm plant height at 40 DAT.

• Journal of the Korean Society of Tobacco Science
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• v.25 no.2
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• pp.154-159
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• 2003

Using sucker agents for tobacco can lead some advantages including saving labor, increasing yield and reducing the spread of diseases. At present, the sucker control agents used in China mainly depended on importing. The agents includes two groups, systemics (Maleic hydrazide: MH, etc) and partial systemics (Butralin, Flumetralin, Pendimethalin, etc). Now, Pendimethalin(a.i. 33%, wp) was used extensively all over the tobacco field in China. Sucker control agents will also be used for tobacco production in China. Because of the high price of the imported agents, China has studied on the domestic production of tobacco sucker control agents and has made some progresses.

• Applied Chemistry for Engineering
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• v.18 no.6
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• pp.537-544
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• 2007

This study was carried out to investigate adsorption characteristics of residual pesticides on an adsorbent. $Bauxsol^{TM}$ and mackban-stone as adsorbent were used. Analytical method for residual pesticides was established by GC/NPD and $GC/{\mu}ECD$. Pesticides used in this study were ${\alpha}$-endosulfan, ${\beta}$-endosulfan, pendimethalin and chlorpyrifos-methyl, fenitrothion, and recovery rates were more than 97%. Adsorption rate on an adsorbent was decreased in order of endosulfan, chlorpyrifos-methyl, pendimethalin, fenitrothion. Organochlorine pesticides showed higher removal rate than the other pesticides. $Bauxsol^{TM}$ gave both chemical decomposition and physical adsorption. Mackban-stone gave only physical adsorption on the other hand. The high pH and chloric ions structure of eluted solution have greatly affected at chemical resolution. The removal rate of pesticides was increased due to the physical property of adsorbent, i.e. high porosity. The above adsorbent is to be a candidate to remove residual pesticides in water and pond of links.

• Journal of Animal Science and Technology
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• v.61 no.4
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• pp.185-191
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• 2019

The aim of this study was to evaluate different herbicides for optimum growth, yield and nutritive value of corn-soybean mixed forage under randomized complete block design. The experimental site was selected and divided equally into 3 blocks. Each block was further divided into 5 plots that each plot had 15 square meter space ($3{\times}5$). Five herbicidal treatments were randomly applied over 5 plots and herbicides were used under 5 herbicidal treatments, viz. 1) No herbicide (control); 2) Pendimethalin; 3) Linuron; 4) S-metolachlor and 5) Ethalfluralin. The collected data were analyzed using ANOVA through SAS 9.1.3 software. The results indicated that growth characteristics were not influenced (p > 0.05) by any herbicide. However, arithmetically corn stalk height was highest in the field of Pendimethalin treatment, whereas highest soybean height was found in the field of S-metolachlor. Arithmetically dry matter (DM) yield was increased with herbicidal treatments as compared to that of control treatment. Relatively highest DM yield (130%) was recorded in the treatment of Ethalfluralin followed by Pendimethalin (126%), S-metolachlor (126%) and Linuron (108%) as compared to that of control treatment. The weed emergence was significantly reduced in all herbicidal treatments as compared to that of control (p > 0.05), but the difference among herbicidal treatments was non-significant. It was concluded that weed emergence can be effectively controlled by use of any tested herbicide. However, optimum DM yield can be achieved through using herbicides; Ethalfluralin, Pendimethalin and S-metolachlor.

• Korean Journal of Weed Science
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• v.18 no.1
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• pp.63-68
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• 1998

This experiment was carried out to select some herbicides for edible wild greens, Album monanthum, Petasites japonicus, and Aster scaber. The herbicides tested were napropamide 21.8% EC, nitralin 50% WP, and pendimethalin 31.7% EC. Dorminant weeds in the field were Echinochloa crus-galli, Digitaria sanguinalis, Persicaria hydropiper, Chenopodium album, and Siegesbeckia pubescens. Simpson's index was calculated to 0.26~0.30, which showed that weed occurrence in the field was quite various. Control efficacy in the field treated with napropamide EC 872g(ai/ha)., nitralin WP 1,000g(ai/ha), and pendimethalin EC 634g(ai/ha) were 81.4%~85.6%, 79.4%~82.8%, and 86.8%~92.2%, respectively. The typical phytotoxic symptoms to herbicides were germination inhibition, growth retardation, and malformation.

• Korean Journal of Environmental Agriculture
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• v.25 no.4
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• pp.297-305
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• 2006

The field lysimeter experiment were undertaken to investigate the runoff and erosion loss of four pesticides from sloped land by rainfall and to assess the influence of pesticide properties, environmental factors and agricultural practices on them. The pesticide losses from soybean planted field and bare field were measured using field lysimeters. Pesticide losses from a series of lysimeter plots of sloped land by rainfall ranged $0.1{\sim}0.6%$ for alachlor, $1.1{\sim}4.5%$ for ethalfluralin, $8{\sim}31%$ for pendimethalin and 0.03% for ethoprophos, which were $1/3{\sim}2.5$ times to them in the simulated rainfall study. The erosion loss rates of pesticides from soybean-plots were $21{\sim}75%$ lower than the ones from bare soil plot. The effect of slope conditions was not great for runoff loss, but for erosion loss increased to maximum $4{\sim}12$ times by sloping degree and slope length. The peak runoff concentration in soybean-plots and bale soil plots were $3{\sim}278{\mu}gL^{-1}\;and\;6{\sim}450{\mu}gL^{-1}$ for alachlor, $1.1{\sim}11.4{\mu}gL^{-1}\;and\;0.9{\sim}16{\mu}gL^{-1}$ for ethalfluralin, $7{\sim}42{\mu}gL^{-1}\;and\;6{\sim}66{\mu}gL^{-1}$ for pendimethalin, and $2{\sim}53{\mu}gL^{-1}\;and\;0.1{\sim}113{\mu}gL^{-1}$ for ethoprophos, respectively, on nine different slope degree and slope length plots. Therefore, the differences of the peak runoff concentration between bare soil plots and soybean-plots were not great.

• Radioisotope journal
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• v.20 no.2
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• pp.20-24
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• 2005

• Analytical Science and Technology
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• v.30 no.4
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• pp.194-204
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• 2017

Direct injection (DI) and solid phase extraction (SPE) methods for the simultaneous determination of pendimethalin (PDM) and dinoseb (DNS) in environmental water have been optimized using the ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. The limits of quantification (LOQs) of PDM and DNS were $0.01{\mu}g/L$ using the DI method and $0.0001-0.0002{\mu}g/L$ using the SPE method. The precision by SPE UPLC-MS/MS was less than 11 % for intra-day and inter-day analyses. When the proposed SPE method was used to analyze two analytes in environmental water, PDM was detected in a concentration range of $0.0002-0.011{\mu}g/L$ in 31 samples of the 114 surface water samples, and DNS was detected in a concentration range of $0.0005-0.045{\mu}g/L$ in 17 samples of the 114 surface water samples analyzed. When the DI method was used to analyze target compounds in the same samples, the detected concentrations of the two analytes were within 21% in samples with concentrations above $0.01{\mu}g/L$. The DI UPLC-MS/MS method can thus be used for the routine monitoring of PDM and DNS in environmental water, and the SPE LC-MS/MS method can be used for the determination of the ultra-trace PDM and DNS residues in environmental water.

• Korean Journal of Environmental Agriculture
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• v.36 no.2
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• pp.80-86
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• 2017

BACKGROUND: Pesticides is exposed in an aquatic environment and effected to benthic animals. Especially, sediment-associated pesticides is required for determination of sediment toxicity on aquatic organisms. This study was conducted to evaluate the impact of six pesticides (chlorfluazuron, difenoconazole, dithianon, flufenoxuron, flutianil, pendimethalin) on Chironomus riparius in aquatic ecosystems. METHODS AND RESULTS: Chlorfluazuron, difenoconazole, dithianon, flufenoxuron, flutianil and pendimethalin were used as a model compounds, which have a sediment-associated potential ($K_{oc}$>3). Acute and chronic toxicity tests on Chironomus riparius were performed at six concentrations of each pesticide with four replicates of each based on OECD test guideline 235 and 218. The calculated 48-h $EC_{50}$ values of chlorfluazuron, flutianil, pendimethalin, difenoconazole, dithianon and flufenoxuron were 6.72, 2.55, 2.27, 0.77, 0.30 and 0.11 mg/L, respectively. Flufenoxuron was the lowest 48-h $EC_{50}$ value in this study. The No Observed Effective Concentration (NOEC) and the Lowest Observed Effect Concentration (LOEC) of flufenoxuron for Chironomus riparius in 28-days test were 30 and $60{\mu}g/kg$, respectively. CONCLUSION: Pesticides of the sediment-associated have the potential effect for Chironomus riparius in aquatic ecosystems. Therefore, sediment toxicity assessment of these pesticides should be further investigated to evaluate the impact to benthic organisms.

• Asian Journal of Turfgrass Science
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• v.10 no.3
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• pp.263-270
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• 1996

This experiment was conducted to investigate the loss of various herbicides by means of vola-tility from the turfgrass field and the hare ground with the different soil moisture contents and temperatures. Different herbicides were applied at the rates of 375 g a.i. /l0a of pendimethalin,250 g a.i. /l0a of napropamide, and 96.4 g a.i. /l0a of dicamba with 200 \ulcorner/10a of spray volume in the turfgrass(Zoysia japonica cut off 5cm) grown in pots(265.8 $cm^2$) and bared soil. The pots were placed in the growth chamber with 10,000 lux of light intensity(12h per day) at 25 and 35˚C for 7days. Amberlite XAD polymeric resin(20/50 mesh) was used as sampling media for herbicide airborne residues. Air flow was maintained at 10 \ulcorner /min by vacuum pump regulated with a factory calibrated flow meter. Herbicide airborne residues were extracted from the XAD resin with 300 ml of 1:1 acetone and hexane. The extracts were concentrated by rotary evaporation at 35˚C and dissolved in 1 ml MeCN for HPLC analysis. The airborne losses of the herbicide applied in the turfgrass and bare soil increased as the temperature and soil moisture contents were increased, regardless of the kinds of herbicide. Higher airborne residues was observed in the turfgrass pots than the bare soil pots. Pendimethalin and dicamba with higher vapor pressure gave rise to the increased loss of airborne herbicides, showing that 6.26 and 6.4% of average airborne loss in pendimethalin and dicamba, respectively, compared to 0.56% in napropamide. The amount of airborne losses in turfgrass was highest at one day after application and then a declined trend was observed as the time was prolonged. Key words. Herbicides, Turfgrass field, Bare ground, Volatility.