Kan suksa khwam khongthon khong haloxifopmethyl nai din lae kha LC50.
1984
Rungsit Suwanketnikom | Montri Toopornsiri | Suwit Suraneeranart
Soil was clay consisting of 3.46 percent organic matter, 17 percent sand, 30 percent silt, 53 percent clay, 34 ppm phosphorus, 190 ppm potassium and pH 4.1. Soil was packed into the polyethylene column with 10.8 cm. diameter and 30 cm. length. Herbicide was applied at the rate of 0.125, 0.25, 0.5 and 1 kg (ae)/ha to the soil surface. After 0, 2, 4, 6, 8, 10, and 12 weeks of application, Suwan 1 corn and Gold Finger sorghum were used as indicator. Dry weight of both plants were compared with standard curve and calculated to determine herbicide concentration. It was found that haloxifopmethyl at the rate of 0.125, 0.25 and 0.5 kg (ae)/ha has disappeared in the soil within 6 weeks after application. At a very high rate of 1 kg (ae)/ha, it remained in the soil until 12 weeks at the concentration of 0.016 and 0.0332 ppm. Therefore, when haloxifopmethyl was applied at normal rate in cotton or soybean, the following crops, corn or sorghum can be grown without phytotoxicity. Puntius gonionotus Bleeker, with the length of 3.0 cm and weight of 0.61 gm. and Tilapia nilotica Linn, with the length of 3.0 cm. and weight of 0.9 gm. were used to study LC50 of haloxifopmethyl in the laboratory. The concentration of herbicide that killed 50 percent at P. gonionotus and T. nilotica was 1.89 ppm (0.66 - 2.48 ppm) and 4.97 ppm (3.59-6.89 ppm), respectively.
显示更多 [+] 显示较少 [-]