Efficacy of ethylenesulphonyl fluoride against stored grain psocids, Liposcelis bostrychophila Badonnel and Liposcelis entomophila (Enderlein)

Phase-out, impending ban, and developing insect resistance to the commonly used insecticides for stored grains pose serious challenges to the scientific community and it is imperative to develop effective pest management strategies. Identification and testing of new compounds are potential options to deal with the growing threat. Ethylenesulphonyl fluoride (ESF), a new synthetic compound, is one of the most promising alternative fumigant insecticides that can be used to control the insect pests in stored-grains. However, limited evidence is available to support its efficacy to control the stored-product psocids. This study evaluates the ESF as a prospective control reagent to exterminate different life stages of the psocids Liposcelis bostrychophila Badonnel and L. entomophila (Enderlein). We conducted a 4 h toxicity trials and 12 h simulated efficacy trials with adults of the two species in wheat. Adults and nymphs were highly susceptible to ESF. Complete adult and nymph mortality (LD99) was also recorded at dosages ranged from 1.97 μL/L to 3.80 μL/L. Moreover, complete (LD99) egg mortality was recorded at dosages between 3.59 μL/L and 7.60 μL/L. Remarkably, the mortality of adults decreased with increasing depth of the grain bulk. Our study establishes ESF as a potential reagent that can be used effectively to control a variety of commonly known stored grain psocids.