Photodegradation of Butachlor and Pyrazosulfuron-ethyl in Rice Paddy Water under Natural Sunlight

• Published in: Hanguk hwangyeong nonghak hoeji Vol. 33; no. 2; pp. 134 - 137
• Main Authors: Ok, Junghun, Watanabe, Hirozumi, Cho, Junglai, An, Nanhee, Lee, Byungmo
• Format: Journal Article
• Language: English
• Published: 한국환경농학회 30.06.2014
• Subjects: 농학
• ISSN: 1225-3537; 2233-4173
• DOI: 10.5338/KJEA.2014.33.2.134

BACKGROUND: Dissipation of herbicides in paddy watervaries significantly, being dependent on environmentalconditions such as sunlight. The photodegradation undernatural sunlight may be one of natural degradation routes ofherbicides dissipation. Therefore, the aim of this study wasto monitor the degradation of butachlor and pyrazosulfuronethylin paddy water under natural sunlight. METHODS AND RESULTS: The 12 water sample bottlesof treatment were covered by quart glass plates, whichallow about 90% of UV radiation (280-2000 nm) to passthrough, to minimize the UV attenuation. The other 12water sample bottles of the control were covered by glasslids and wrapped with aluminum foils to prevent thesunlight. The concentration of butachlor and pyrazosulfuronethylin paddy water samples bottles was monitored underambient conditions with and without natural sunlight. Theconcentration of butachlor and pyrazosulfuron-ethyl fortreatment decreased from 355.3 μg/L to 37.8 μg/L and from10.5 μg/L to 3.9 μg/L, respectively, during consecutive 21days after herbicide application under natural sunlight. CONCLUSION: The concentration of butachlor in paddywater decreased quickly under ambient conditions withnatural sunlight. The degradation of butachlor in paddywater was enhanced by the natural sunlight. However, thedegradation of pyrazosulfuron-ethyl was insignificantunder natural sunlight. KCI Citation Count: 1