Abstract:
Tribolium castaneum (Red Flour Beetle) is a cosmopolitan storedproduct
pest. Commercially available pheromone traps baited with its
aggregation pheromone 4, 8-dimethyldecanal (4, 8 DMD) have a low
trapping efficiency. Effects of biorational insecticides on orientation of T.
castaneum have been reported. However, no such investigation has been
carried out using spinetoram. Therefore, the objective of our study aimed
to determine the effect of spinetoram on traps to catch of T. castaneum
adults. The attraction of spinetoram pre-exposed to T. castaneum
adults to pheromone traps were investigated under laboratory
(experiment 1) and warehouse (experiment 2) conditions. Under
laboratory conditions, the trapping of adults pre-exposed to spinetoram
significantly differed from the respective control at each concentration.
The highest trap catch (61.33%) was recorded on exposure to 31.25 ppm
of spinetoram. The lowest trapping occurred at 0 ppm of spinetoram
(water control). Under warehouse conditions, the highest trap catch was
at 31.25 ppm and 46.875 ppm of spinetoram with no significant difference
among them. The lowest trapping occurred at 0 ppm of spinetoram/ water
control. The value obtained at 62.5 ppm was not significantly different
from the value at 0 ppm. Our study showed that the pre-exposure to
spinetoram enhanced the orientation of T. castaneum adults to
pheromone traps baited with 4, 8 DMD, and the response was dose
dependent. The observations made in this research may be useful in
enhancing trapping efficiency of commercially available pheromone traps.
