Mobility and Adsorption Behavior of Flubendiamide in Soil

Increasing the amount of percolating water from 20 mL(equivalent to 51.92 mm rainfall) to 160 mL (equivalent to 415.42 mm rainfall) increased the downward mobility of flubendiamide. Major portion of the soil applied formulation of flubendiamide (67.22%) was recovered from the top 0-5 cm soil layer after passing 160 mL water. After percolating 160 mL of water (equivalent to 415.42 mm rainfall) analytical grade flubendiamide leached down upto 15-20 cm depth and 68.06% of the applied insecticide was retained in the top 5-10 cm layer. Metabolite desiodo flubendiamide was detected in 20-25 cm layer (9.47%) after passing 160 mL water because of its higher mobility. Adsorption of flubendiamide was positively related with organic matter content and negatively with pH. The sorption coefficient values studied in two different soil orders ranged from 1.07 in topsoil from Inceptisol and 2.13 in topsoil from Alfisol. The higher cumulative desorption and proportional desorption in topsoil from Inceptisol than in topsoil from Alfisol may be due to lower organic carbon content of the former than the latter.