Environ Monit Assess DOI 10.1007/s10661-013-3611-7
Influence of microbial community on degradation of flubendiamide in two Indian soils Shaon Kumar Das & Irani Mukherjee
Received: 30 August 2013 / Accepted: 23 December 2013 # Springer Science+Business Media Dordrecht 2014
Abstract Degradation of flubendiamide as affected by microbial population count in two Indian soils (red and alluvial) varying in physicochemical properties was studied under sterile and non-sterile conditions. Recovery of flubendiamide in soil was in the range of 94.7–95.9 % at 0.5 and 1.0 μg g−1, respectively. The DT50 of flubendiamide at the level of 10 μg g−1 in red soil under sterile and non-sterile conditions was found to be 140.3 and 93.7 days, respectively, and in alluvial soil under sterile and non-sterile condition was 181.1 and 158.4 days, respectively. Residues of flubendiamide dissipated faster in red soil (non-sterile followed by sterile) as compared to alluvial (non-sterile soil followed by sterile soil). A wide difference in half-life of red and alluvial soil under sterile and non-sterile conditions indicated that the variation in physicochemical properties of red and alluvial soil as well as the presence of microbes play a great role for degradation of flubendiamide. The results revealed that slowerdegrading alluvial soil possessed microbes with degradative capacity. The degradation rate in this soil was significantly reduced by some of its physicochemical S. K. Das : I. Mukherjee (*) Division of Agricultural Chemicals, Indian Agricultural Research Institute, New Delhi, India 110012 e-mail: [email protected] S. K. Das e-mail: [email protected] Present Address: S. K. Das ICAR RC for NEH Region, Sikkim Centre, Sikkim 737102, India
characteristics, despite sterile and non-sterile conditions, which was faster in red soil. Keywords Degradation . Residues . Sterile . Non-sterile . Red soil . Alluvial soil
Introduction Soil microorganisms play an important role in degradation of pesticides and are vital in ecosystem processes (Maisnam et al. 2009). They are responsible for decomposition of organic material and available nutrient cycle. The presence of huge diversity of microbial communities in soil provides the potential for a wide range of soil reactions, but it is very difficult to distinguish the roles of different microbial community composition and soil physicochemical properties in ecosystem processes. Probably this reduces the ability to predict the influence of environmental changes and different management strategies on ecosystem functions (Prosser 2002). Rate of degradation in soil depends on the microbial community present in soil and different physicochemical properties like soil texture (Choi et al. 1988), composition of organic matter (Xing and Pignatello 1997), soil pH (Walker et al. 2001), mode of action of pesticide, chemical structure, etc. Hence, degradation rate of pesticide varying between soils may therefore result from differences in soil physicochemical properties as well as microbial community composition. Flubendiamide, N2-[1,1-dimethyl2-(methylsulfonyl)ethyl]-3-iodo-N1-[2-methyl-
Environ Monit Assess
4-[1,2,2,2-tetrafluoro-1-trifluoromethyl)ethyl]phenyl]1,2-benzene dicarboxamide, belongs to phthalic acid diamide group. It is mainly effective for controlling lepidopteron pests including resistant strains in rice, cotton, corn, grapes, other fruits and vegetables (Tohnishi et al. 2005). It has a novel biochemical action as it affects calcium ion balance irrespective of sodium or potassium ion balance which causes contraction of insect skeletal muscle (Masaki et al. 2006). Flubendiamide has a favourable ecological, ecotoxicological and environmental profile with low mammalian toxicity and no genotoxic, mutagenic or oncogenic properties (Shane 2006). The logP and vapour pressure are approximately 4.2 and
Influence of microbial community on degradation of flubendiamide in two Indian soils Shaon Kumar Das & Irani Mukherjee
Received: 30 August 2013 / Accepted: 23 December 2013 # Springer Science+Business Media Dordrecht 2014
Abstract Degradation of flubendiamide as affected by microbial population count in two Indian soils (red and alluvial) varying in physicochemical properties was studied under sterile and non-sterile conditions. Recovery of flubendiamide in soil was in the range of 94.7–95.9 % at 0.5 and 1.0 μg g−1, respectively. The DT50 of flubendiamide at the level of 10 μg g−1 in red soil under sterile and non-sterile conditions was found to be 140.3 and 93.7 days, respectively, and in alluvial soil under sterile and non-sterile condition was 181.1 and 158.4 days, respectively. Residues of flubendiamide dissipated faster in red soil (non-sterile followed by sterile) as compared to alluvial (non-sterile soil followed by sterile soil). A wide difference in half-life of red and alluvial soil under sterile and non-sterile conditions indicated that the variation in physicochemical properties of red and alluvial soil as well as the presence of microbes play a great role for degradation of flubendiamide. The results revealed that slowerdegrading alluvial soil possessed microbes with degradative capacity. The degradation rate in this soil was significantly reduced by some of its physicochemical S. K. Das : I. Mukherjee (*) Division of Agricultural Chemicals, Indian Agricultural Research Institute, New Delhi, India 110012 e-mail: [email protected] S. K. Das e-mail: [email protected] Present Address: S. K. Das ICAR RC for NEH Region, Sikkim Centre, Sikkim 737102, India
characteristics, despite sterile and non-sterile conditions, which was faster in red soil. Keywords Degradation . Residues . Sterile . Non-sterile . Red soil . Alluvial soil
Introduction Soil microorganisms play an important role in degradation of pesticides and are vital in ecosystem processes (Maisnam et al. 2009). They are responsible for decomposition of organic material and available nutrient cycle. The presence of huge diversity of microbial communities in soil provides the potential for a wide range of soil reactions, but it is very difficult to distinguish the roles of different microbial community composition and soil physicochemical properties in ecosystem processes. Probably this reduces the ability to predict the influence of environmental changes and different management strategies on ecosystem functions (Prosser 2002). Rate of degradation in soil depends on the microbial community present in soil and different physicochemical properties like soil texture (Choi et al. 1988), composition of organic matter (Xing and Pignatello 1997), soil pH (Walker et al. 2001), mode of action of pesticide, chemical structure, etc. Hence, degradation rate of pesticide varying between soils may therefore result from differences in soil physicochemical properties as well as microbial community composition. Flubendiamide, N2-[1,1-dimethyl2-(methylsulfonyl)ethyl]-3-iodo-N1-[2-methyl-
Environ Monit Assess
4-[1,2,2,2-tetrafluoro-1-trifluoromethyl)ethyl]phenyl]1,2-benzene dicarboxamide, belongs to phthalic acid diamide group. It is mainly effective for controlling lepidopteron pests including resistant strains in rice, cotton, corn, grapes, other fruits and vegetables (Tohnishi et al. 2005). It has a novel biochemical action as it affects calcium ion balance irrespective of sodium or potassium ion balance which causes contraction of insect skeletal muscle (Masaki et al. 2006). Flubendiamide has a favourable ecological, ecotoxicological and environmental profile with low mammalian toxicity and no genotoxic, mutagenic or oncogenic properties (Shane 2006). The logP and vapour pressure are approximately 4.2 and
