• Title/Summary/Keyword: %EC%83%81%EC%A7%95

Search Result 2, Processing Time 0.018 seconds

Distribution of Pesticide Applied with Different Formulations and Rice Growing Stages in Paddy Fields (벼 재배환경에서 생육단계에 따른 제형별 살포농약의 분포특성)

  • Park, Byung-Jun;Park, Sang-Won;Kim, Jin-Kyoung;Park, Kyung-Hun;Kim, Won-Il;Kwon, Oh-Kyung
    • The Korean Journal of Pesticide Science
    • /
    • v.12 no.1
    • /
    • pp.74-81
    • /
    • 2008
  • To elucidate the exposure of pesticide in agricultural environment and to investigate distribution of pesticide in paddy fields. This experiment was carried out to clarify pesticide distribution in paddy fields applied with different formulations and growing stages. Initial dissipation rate of applied butachlor EW and oxadiazon EC before rice planting were more than 90% within 3 days in paddy fields. The distribution of a.i. in the pesticide formulations tested depended upon the elapsed time at each growing stage of rice plant after application. Most of pesticides applied within 15 days after transplanting of rice seedlings, more than 95%, were located in the surface water and soil regardless of pesticides; butachlor, thiobencarb and molinate GR. The distribution of iprobenfos GR, tricyclazole WP and phenthoate EC, after application 2 hours in middle growing stage (46 days after rice planting) were shown as 16.1, 48.9 and 38.9% in surface water, 83.6, 15.4 and 10.7% in soil, and 0.3, 35.7 and 50.4% in rice plants of paddy fields, respectively. Also tricyclazole WP and phenthoate EC, after application 2 hours in the late rice growing stage (90 days after rice planting) were distributed to 7.8 and 9.8% in surface water, and 21.7 and 5.1% in soil, and 70.5 and 85.1% in rice plants of paddy fields, respectively.

Optimization of Analytical Methods for Ochratoxin A and Zearalenone by UHPLC in Rice Straw Silage and Winter Forage Crops (UHPLC를 이용한 볏짚 사일리지와 동계사료작물의 오크라톡신과 제랄레논 분석법 최적화)

  • Ham, Hyeonheui;Mun, Hye Yeon;Lee, Kyung Ah;Lee, Soohyung;Hong, Sung Kee;Lee, Theresa;Ryu, Jae-Gee
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.36 no.4
    • /
    • pp.333-339
    • /
    • 2016
  • The objective of this study was to optimize analytical methods for ochratoxin A (OTA) and zearalenone (ZEA) in rice straw silage and winter forage crops using ultra-high performance liquid chromatography (UHPLC). Samples free of mycotoxins were spiked with $50{\mu}g/kg$, $250{\mu}g/kg$, or $500{\mu}g/kg$ of OTA and $300{\mu}g/kg$, $1500{\mu}g/kg$, or $3000{\mu}g/kg$ of ZEA. OTA and ZEA were extracted by acetonitrile and cleaned-up using an immunoaffinity column. They were then subjected to analysis with UHPLC equipped with a fluorescence detector. The correlation coefficients of calibration curves showed high linearity ($R^2{\geq_-}0.9999$ for OTA and $R^2{\geq_-}0.9995$ for ZEA). The limit of detection and quantification were $0.1{\mu}g/kg$ and $0.3{\mu}g/kg$, respectively, for OTA and $5{\mu}g/kg$ and $16.7{\mu}g/kg$, respectively, for ZEA. The recovery and relative standard deviation (RSD) of OTA were as follows: rice straw = 84.23~95.33%, 2.59~4.77%; Italian ryegrass = 79.02~95%, 0.86~5.83%; barley = 74.93~97%, 0.85~9.19%; rye = 77.99~96.67%, 0.33~6.26%. The recovery and RSD of ZEA were: rice straw = 109.6~114.22%, 0.67~7.15%; Italian ryegrass = 98.01~109.44%, 1.65~4.81%; barley = 98~113.53%, 0.25~5.85%; rye = 90.44~108.56%, 2.5~4.66%. They both satisfied the standards of European Commission criteria (EC 401-2006) for quantitative analysis. These results showed that the optimized methods could be used for mycotoxin analysis of forages.