Climatically Isolated Populations of Habrobracon hebetor Say (Hymenoptera: Braconidae) Demonstrate Striking Differences in Life History Traits

Augmentative release of native natural enemies is a prominent strategy for suppression of crop pests. Intrinsic differences among populations of natural enemies may affect their efficiency in pest management programs. We characterized life history traits of 13 climatically and geographically isolated populations of Habrobracon hebetor Say (Hymenoptera: Braconidae) from different regions of Iran to assess their suitability for biological control of noctuid moths. All experiments were performed at 25±1°C, 65±5 RH and 16:8 (L:D) hours photoperiod regime. Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae) was used as a laboratory host. Our results revealed significant variation in female longevity, paralysis and parasitism rate, sex ratio, reproductive rate and host allocation among different H. hebetor populations tested. The highest number of offspring (124.2) and parasitized larvae (160.1) were observed in Bandar Lengeh and the lowest ones was observed in Urmia and Jiroft, respectively (3.4 and 9.3 for Urmia and 3.1 and 10.1 for Jiroft). Also, the wasps of Bandar Lengeh paralyzed more than 95% of the introduced host larvae. The longest female longevity and male production (21.3 days and 80.1, respectively) were in Bandar Abbas and Bandar Lengeh (21.3 days and 80, respectively), while the lowest ones were in Dehloran (12.9 days and 40.2, respectively). Gorgan population deployed the highest number of Ephestia kuehniella larvae in foraging behavior test. These results show considerable variation in the life history traits of various populations of H. hebetor, which may affect performance of these populations under field condition.