Sub-lethal effect of combination of Metarhizium anisopliae and imidacloprid on life table of Myzus persicae (Hem.: Aphididae)

The sub-lethal effect of Metarhizium anisopliae and imidacloprid as well as combination of the two control agents was examined on life table parameters of Myzus persicae on different cultivars of canola under laboratory condition at 25 ± 1 ºC, 85% RH and photoperiod of 16L: 8D. The offspring resulting from fungus-infested adults were placed onto leaf discs in Petri dishes separately to record their development time till they reached to adulthood. The number of nymphs produced by each adult aphid was recorded daily. The intrinsic rate of increase(rm) had no significant differences among the three cultivars, and was nearly similar to the net reproductive rate (R0). The concurrent application of M. anisopliae and imidacloprid significantly shortened the aphid longevity on the RGS003 cv compared to the other cultivars. The type of cultivars had no impact on the finite rate of increase (λ) of green peach aphid in any of the treatments. The values of T showed that there was no significant difference among the treatments. Despite having no significant effect on life table characteristics of M. persicae by most of the treatments, the method would be a favorable procedure to control the aphid by raising the fungal concentration. Conducting such research would be worthwhile since there are no antagonistic interactions between the entomopathogenic fungus and the insecticide.