Reproductive compatibility among different populations of Anastrepha fraterculus: disentangling the importance of sexual behavior, chemical communication and postzygotic compatibility.

JUAN RULL; SOLANA ABRAHAM; ADALECIO KOVALESKI; CLARA LIENDO; MARIANA MENDOZA; A. BARTOULCCI; DIEGO SEGURA; M. TERESA VERA

Brisbane

Congreso; 2nd RESEARCH COORDINATION MEETING “Resolution of Cryptic Species Complexes of Tephritid Pests to Overcome Constraints to SIT Application and International Trade”; 2012

As a follow up of the studies initiated to evaluate the reproductive compatibility among different populations of Anastrepha fraterculus, mating compatibility evaluations were carried out with the colonies available at the International Atomic Energy Agency Laboratories in Seibersdorf, Austria: Xalapa (Mexico), Piura (Perú), Vacaria, Piracicaba and Pelotas (Brazil) and Tucumán (Argentina). Different degrees of sexual isolation were found among the tested populations: Mexico and Peru were isolated from all the populations from which they were evaluated while the populations from southern Brazil (Vacaria and Pelotas) were found to be compatible with the one from Argentina. In the later case, mating duration was not affected by fly origin and there was no evidence of spatial partition of mating location. Homotypic and heterotypic crosses for all possible combinations displayed similar levels of fertility and yielded F1 adults without distortion of the sex ratio. F1 hybrid and parental adults produced equally viable F2 eggs. The population from Piracicaba showed an intermediate level of isolation when confronted with the population from the putative A. sp. 1 aff. fraterculus from Argentina. Put together, our results suggest that a large area ranging from Buenos Aires to the surroundings of São Paulo could be managed using a single A. fraterculus strain. At the northern margin of this area two A. fraterculus morphotypes appear to coexist in sympatry. Additionally we evaluated the remating behaviour of females mated with males from their own origin or from another population. The time elapsed between the first and second copula (refractory period) was similar for the all the mating combinations while the remating rates were different. Finally, we performed pheromone collections and initiated studies to characterize male accessory glands’ proteins.