Alternative fumigants to methyl bromide for the control of pest infestation in grain and dry food products

The primary aim of the current study is to evaluate the potential use of the known isothyiocyanates (ITC) as compared to a new ITC isolated from Eruca sativa (salad rocket) as fumigants for the control of stored products insects. The biological activity of methyl iodide (CH3I), carbon disulphide (CS2), benzaldehyde (C7H60) and essential oils were also evaluated. The toxicity of the various fumigants was assessed against adults and larvae of a number of major stored-product insects. ITCs are potential candidates because only very low concentrations are needed for the control of stored-product insects. It should be mentioned that Eruca sativa is used worldwide as a food supplement. Methyl thio-butyl ITC the main bioactive component in this plant has high toxicity against insects, but lower mammalian toxicity as compared to other active ITCs. Comparative studies with CH3I, CS2 and C7H60 showed that the first was the mot active compound against stored-product insects followed by the second and the third. CH3I was found less sorptive and to be less penetrative in wheat than CS2. The activity of some essential oils was also evaluated. In this context, we should keep in mind that a general consensus is very difficult to achieve in order to introduce broadspectrum fumigants like methyl bromide or phosphine. Because of this, alternative fumigants could be developed against particular species of insects or to be used for specific food product commodity. Keywords: Fumigants; Isothiocyanates; Methyl iodide; Carbon disulfide; Benzaldehyde