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It became clear during the discussions that there is still a considerable amount of information lacking with respect to the ecology of LGB. In particular it would be useful to know whether LGB is principally a pest of maize / cassava or rather a wood borer that only sporadically and secondarily attacks these crops. It was likewise unclear why LGB has spread rapidly in some countries and relatively much more slowly in others. Linked to this it was suggested that more effort should be spent looking at flight activity patterns of LGB with the proviso that pheromone trap catch data be interpreted with care.
Although LGB has yet to be found breeding in the wider environment it was pointed out that it has been shown capable of breeding in cassava stems as well as occurring in maize stems and in flame trees.
Participants were reminded of the importance of LGB to the inter-African grain trade but at the same time the of danger that commerce itself poses as a major means of spread of the insect. It was agreed that it was important that treatment of stocks destined for export should be properly treated and that in order to engender confidence in the recipient countries fumigation, quarantine and inspection methods should be improved in the affected countries.
Some concern was shown at the possibility of LGB developing insecticide resistance in the field as it has clearly been shown capable of doing under laboratory conditions. It was however noted that despite the importance of testing for resistance, it could not be considered a priority for financially hard pressed national programmes. At the same time it was pointed out that T. nigrescens, as has been shown, is susceptible to those insecticides currently used against LGB, and that would affect both the efficacy and the sphere of activity of the insect after its release.