Technical improvement of the Detia Degesch Phosphine Tolerance Test Kit

Phosphine is the most important commonly used fumigant for the control of stored product insects in warehouses and processing facilities globally. However, the improper and extensive use has led to reduced susceptibility to phosphine for several insect species and strains in many parts of the world. To evaluate and quantify this phenomenon, Detia Degesch developed the Detia Degesch Phosphine Tolerance Test Kit (DDPTTK) more than 10 years ago. The use of DDPTTK is based on the exposure of the insects on a high concentration of phosphine (e.g. 3000 ppm) for short exposure periods (e.g. 8-15 min). This kit can be used on site by the fumigation and food industry, and can provide immediate results on the tolerance status of the insect strains that are to be treated. So far, the instructions of DDPTTK refer only to a six insect species. In this work, data for the expansion of knowledge about other species is provided, in order to broaden the spectrum of cases where the kit can be used. Moreover, certain improvements for the use of the kit are introduced, i.e. practical recommendations on the procedure and safety instructions.