Geometric Morphometric Study on Geographic Dimorphism of Coding Moth Cydia Pomonella (Lepidoptera, Tortricidae) from North West of Iran

During years 2003-2004, nine geographical populations of codling moth Cydia pomonella (Linnaeus) from 4 north western provinces of Iran were collected. By preparing 575 images from fore wings and 564 from hind wings, a total of 15 and 11 landmarks were determined for fore and hind wings, respectively. With transforming of landmark's geometrical data into partial warp scores, 26 and 18 scores were obtained for fore and hind wings, respectively. Canonical correlation analysis (CCA) revealed significant correlation between environmental parameters and wing shape variables. Among environmental parameters, wind speed showed the highest correlation with wing shape variables whereas, the correlation between latitude, relative humidity as well as amount of precipitation and wing shape variables was low. Considering the effect of various environmental parameters on wing shape, wind speed was determined as important parameter affecting geographic dimorphism. Among the populations collected from different regions, two geographic population pairs; Meshkinshahr-Mahneshan and Zandjan-Khoramdareh were selected as representative of low and high windy regions, respectively. Relative warp analysis (RWA) of fore and hind wings shape variables in the areas with high and low wind showed shorter and wider fore wings as well as slender and narrower hind wings in populations from high windy regions compared with populations from low wind regions. Centroid size of fore and hind wings in high windy area populations were smaller compared with those from low windy ones as revealed by t-test. The results showed aerodynamic shape and small size of wings are as adapted traits for powerful flight and its control in high windy regions.