Concentration-time relationships in phosphine fumigation on different species and strains: the UTH protocol

Abstract: We evaluated different monitoring protocols for phosphine efficacy in adults of
several major stored product beetle species. Different concentrations with exposure time were used here. After the termination of each fumigation, the vials were kept under stable conditions at 25 °C and 65 % relative humidity. Population growth was measured after each exposure interval. Our results show that, the most effective combination (concentration × exposure time) was at 300 ppm for 5 days, which can be utilized further in designing a widely adopted standardized protocol.