Behavior of herbicide pyrazolynate and its hydrolysate in paddy fields after application.
Behavior of the herbicide pyrazolynate, 4-(2,4-dichlorobenzoyl)-1,3-dimethylpyrazol-5-yl p-toluenesulfonate, in paddy water and soil after application to paddy fields was investigated to evaluate the hydrolyzation to destosyl pyrazolynate (DTP), 4-(2,4-dichlorobenzoyl)-1,3-dimethyl-5-hydroxypyrazole. The respective maximum concentrations of pyrazolynate and DTP were 440-1,240 and 200-260 μg/L, respectively, in the paddy water, and 610-860 μg/kg dry and 460-730 μg/kg dry in the paddy soil. The applied pyrazolynate was drained from the paddy fields as DTP. The runoff ratios of DTP from the paddy fields were calculated as 19 % ± 14 %. The respective mean values of the half-lives of pyrazolynate and DTP were 0.87 ± 0.091 and 17 ± 1.4 days in the paddy water and 2.2 ± 0.70 and 26 ± 2.1 days in the paddy soil, respectively.
Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Niigata, Niigata 956-8603, Japan.
Takuya
T
Kubo
Masaki
M
Ohno
Shunsuke
S
Nagasawa
Tomohiro
T
Kose
Kuniaki
K
Kawata
D000383:Agriculture; D004784:Environmental Monitoring; D006540:Herbicides / Q000032:analysis*; D008956:Models, Chemical; D012275:Oryza; D011720:Pyrazoles / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D006540:Herbicides; D011720:Pyrazoles; D014874:Water Pollutants, Chemical; C534728:destosyl pyrazolate