Abstract:
Studies on the attractiveness of various coloured targets for Glossina brevipalpis and G. austeni in
South Africa showed black and pthalogen blue (p.blue) combinations to be the most effective for both
species. A 2 m wide (all targets 1 m high) black/p.blue/black (colour ratio 1 :2: 1) conformation caught
nearly three times more G. brevipalpis and nearly five times more G. austeni than a 1,5 m wide black
standard control target. For G. brevipalpis the black/p.blue/black (1 :2:1) target should be at least 2 m
wide in order to increase catches significantly while a 1,5-2,0 m wide target is optimal for G. austeni.
The p.blue section of a 2 m black/p.blue/black target should not make up less than 20 % of the total
target width for either species. The most effective combination of practical target sizes and colour
ratios were a 1,75 m wide black/p.blue/black (1 :1,5:1) or 2 m wide target (1,5:1 :1,5). Between 61-95%
of G. brevipalpis and 34-90 % of G. austeni that were attracted, settled first on the black section of
black/p.blue targets (> 1 m wide). Further studies revealed that for G. brevipalpis only the black parts
of the 2 m wide target need to be treated with insecticide, while the entire 1,75 m wide target should
be treated. For G. austeni the total width of either target should be treated with insecticide since this
species readily settles on both blue and black.