Degradation of flubendiamide as affected by elevated CO2, temperature, and carbon mineralization rate in soil.

Abstract

An experiment was conducted under three levels of atmospheric CO2 [ambient (398 ± 10μmolmol(-1)), elevated (570 ± 10μmolmol(-1)) and open condition], three levels of temperature (4, 25, and 40°C) to study the degradation pattern of flubendiamide in soil and also carbon mineralization in soil. Results of this study revealed that flubendiamide was found to persist longer under outdoor condition (T1/2, 177.0 and 181.1days) than ambient (T1/2, 168.4 and 172.3days) and elevated condition (T1/2, 159.3 and 155.3days) at 1 and 10μgg(-1) fortification level, respectively. Results also revealed that flubendiamide dissipated faster at 40°C (T1/2, 189.4days) than 25°C (T1/2, 225.3days). Slower dissipation was recorded at 4°C (T1/2, 326.3days). Thus, increased CO2 levels and temperature following global warming might adversely affect flubendiamide degradation in soil. Laboratory study on microbial biomass carbon (MBC) and carbon mineralization (Cmin) in soil revealed that in des-iodo flubendiamide-treated soils, MBC significantly increased up to 45days and then decreased. Flubendiamide-treated soil showed a non-significantly decreasing trend of soil MBC with time up to the 15th day of incubation and after 15days significantly decreased up to 90days of incubation. In des-iodo flubendiamide-treated soil, the evolution of CO2 decreased up to 45days, which was increased after 45days up to 90days. In flubendiamide-treated soil, CO2 evolution decreased up to 30days and after 45days, it increased up to 90days.