دانلود رایگان مقاله تمایز تخم آئدس اجیپتی و آادس notoscriptus با میکروسکوپ الکترونی روبشی

Abstract

Aedes notoscriptus and Aedes aegypti are both peri-domestic, invasive container-breeding mosquitoes. While the two potential arboviral vectors are bionomically similar, their sympatric distribution in Australia is limited. In this study, analyses of Ae. aegypti and Ae. notoscriptus eggs were enabled using scanning electron microscopy. Significant variations in egg length to width ratio and outer chorionic cell field morphology between Ae. aegypti and Ae. notoscriptus enabled distinction of the two species. Intraspecific variations in cell field morphology also enabled differentiation of the separate populations of both species, highlighting regional and global variation. Our study provides a comprehensive comparative analysis of inter- and intraspecific egg morphological and morphometric variation between two invasive container-breeding mosquitoes. The results indicate a high degree of intraspecific variation in Ae. notoscriptus egg morphology when compared to the eggs of Ae. aegypti. Comparative morphological analyses of Ae. aegypti and Ae. notoscriptus egg attributes using SEM allows differentiation of the species and may be helpful in understanding egg biology in relation to biotope of origin.

4. Discussion

Our results demonstrated significant variation in length to width ratio between Ae. aegypti and Ae. notoscriptus eggs, which could be useful for differentiation, as suggested by Linley (1989). Furthermore, intraspecific variations in egg length to width ratio have previously enabled differentiation between multiple Anopheles aquasalis populations (Linley et al., 1993b) as well as several C. quinquefasciatus populations (Suman et al., 2009). Our results also demonstrated between-population variations in egg length to width ratio within both species studied here. Outer chorionic cell morphology has previously been useful in morphometrically distinguishing some Aedes species (Linley et al., 1992). Anterior outer chorionic cell width varied between all eggs excluding Sydney and Adelaide Ae. notoscriptus, and Cairns and Charters Towers Ae. aegypti. Additionally, posterior outer chorionic cell width varied between all groups excluding Sydney and Adelaide and therefore outer chorionic cell width may be, in this case, species specific. The presence of an anterior ring surrounding the micropylar apparatus is also useful in differentiating Ae. aegypti eggs from Ae. notoscriptus eggs.