Different pepper cultivars affect performance of second (Myzus persicae) and third (Diaeretiella rapae) trophic levels

Abstract

Abstract While chemical application can control aphid outbreaks, the overuse of insecticides can make aphids more resistant to these insecticides. These effects make strategies such as host plant resistance combined with biological control agents as an important part of alternative control methods. In this study, the performance of the green peach aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) and its parasitoid wasp, Diaeretiella rapae (McIntosh) (Hymenoptera: Braconidae) were determined on different pepper cultivars (California, Hamedan, Minab, Sabz-Farangi, Sabz-Ghalami, Semnan, Shahroud, and Tehran) in a growth chamber at 25 ± 1 °C, 60 ± 5% RH and a 16:8 h L:D photoperiod. The intrinsic rate of increase (r) of the aphid on the above-mentioned cultivars was 0.3203, 0.3891, 0.3594, 0.3152, 0.3512, 0.3032, 0.3352 and 0.2787 day−1, respectively. Comparison of the intrinsic rate of increase (r) on different pepper cultivars revealed that Hamedan was the most susceptible and Tehran was the most resistant cultivar. The parasitoids reared on the aphids fed on the susceptible cultivar (Hamedan) had a higher intrinsic rate of increase (0.2641 day−1) than those (0.2259 day−1) reared on the resistant cultivar (Tehran). These results demonstrated that the quality of host plant affected the performance of M. persicae and its parasitoid D. rapae.