Geographic patterns of inversion polymorphism in the second chromosome of the cactophilic Drosophila buzzatii from northeastern Argentina

IGNACIO M. SOTO; EDUARDO M. SOTO; VALERIA P. CARREIRA; JUAN HURTADOD; JUAN J. FANARA; ESTEBAN HASSON

JOURNAL OF INSECT SCIENCE

UNIV ARIZONA

Lugar: MADISON; Año: 2010 vol. 10 p. 1 - 11

1536-2442

The inversion polymorphisms of the cactophilic Drosophila buzzatti Patterson and Wheeler(Diptera: Drosophilidae) were studied in new areas of its distribution in Argentina. A total ofthirty-eight natural populations, including 29 from previous studies, were analyzed using multipleregression analyses. The results showed that about 23% of total variation was accounted for by amultiple regression model in which only altitude contributed significantly to population variation,despite the fact that latitude and longitude were also included in the model. Also, inversionfrequencies exhibited significant associations with mean annual temperature, precipitation, andatmospheric pressure. In addition, expected heterozygosity exhibited a negative association withtemperature and precipitation and a positive association with atmospheric pressure. The closesimilarity of the patterns detected in this larger dataset to previous reports is an indication of thestability of the clines. Also, the concurrence of the clines detected in Argentina with thosereported for colonizing populations of Australia suggests the involvement of natural selection asthe main mechanism shaping inversion frequencies in D. buzzatii.Keywords: