A new approach to the control of predatory wasps (Vespa spp.) Of the honeybee (Apis mellifera L.)
R. C. Mishra, Jitender Kumar, And J. K. Gupta
Among five overripe fruits tested as bait for Vespa spp. in an apiary, pear attracted the maximum number of wasps when compared with other fruits. Feeding of poisoned bait ad lib. to the wasps in cages revealed that LT50 values were 180.9, 62.1 and 28.8 min at 100, 200 and 300 mg fenitrothion kg-1 jaggery, respectively. In the newly developed 'capsule cup' technique, one load of poison bait on the thorax of a wasp was shared by more wasps, but the total number of wasps killed did not decrease. With the increase in concentration of bait there was corresponding decrease in LT50 values. A load of 110 mg poison bait (with 1000 ppm fenitrothion) could easily kill 30-35 wasps. In the two field experiments, by sending 25 and 16 loads of poisoned bait, respectively, nests of V. cincta were completely destroyed.