Geometric morphometric approach on the sexual dimorphism of Cydia pomonella (Lep.: Tortricidae) in the North West of Iran

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Abstract

In order to study the sexual dimorphism of codling moth, Cydia pomonella (L.), nine geographical populations were collected from four provinces, East Azarbayjan, West Azarbayjan, Ardebil and Zandjan, in the North West of Iran in autumn 2003. By transforming the landmark geometric data into partial warp scores, 26 and 18 scores were obtained for the fore and hind wings, respectively. Relative warp analysis was performed and wings relative variations in two sexes were determined. Allometry test was carried out after estimating centroid size of individuals. Population-sex interaction was significant in two wings. To determine the contribution of uniform and non-uniform shape variables in explaining populations and sexes differences, MANOVA was performed separately for each type of variables. The result revealed that the non-uniform variables were more effective in determining sex differences in different populations especially in the hind wing. Simple analysis of variance (ANOVA) indicated that the centroid size of females was significantly greater than that of males. Allometry test revealed non significant association between centroid size and wing shape variations in males and females. RWA showed well discrimination between sexes, especially based on the hind wing landmarks. Overall shape deformation indicated wider basal part of wing in females compared with males especially in the hind wing.

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