A geometric morphometric study on geographical Iranian populations of the pod borer, Helicoverpa armigera (Lepidoptera: Noctuidae)

Abstract

Multivariate analyses of the morphological variation in five geographical populations of the pod borer, Helicoverpa armigera (Hübner), was performed using 15 and 12 landmarks selected from the fore- and hindwings respectively. Using their geometric morphometric characters (26 in the forewings and 20 in the hindwings), 287 and 277 images of fore- and hindwings were made respectively. Analyses of size showed the wings of the females are bigger than those of the males (forewing: F = 3.98, P = 0.047; hindwing: F = 14.62, P = 0.000) on populations tested. The discriminant function analysis (DFA) of fore- and hindwings differentiated five geographical populations with 86.1% and 69.3%, respectively. The multivariate analysis of variance (MANOVA) of shape variables in fore- and hindwings indicated significant differences among populations as well as sexes (at least for one of the shape variables). Sex interaction within the populations was significant in fore- and hindwings, particularly based on the hindwing landmarks. The relative warp analysis (RWA) showed well-supported discrimination between sexes. The results showed significant difference between the sexes and also within the populations.

Keywords

• geometric morphometric
• sexual dimorphism
• helicoverpa armigera
• geographical populations