Wolbachia pipiens in laboratory strains of Anastrepha fraterculus and Diachasmimorpha longicaudata

CONTE CLAUDIA ALEJANDRA; JURI MARIANELA; PARREÑO MARIA ALEJANDRA; MANNINO MARIA CONSTANZA; SEGURA DIEGO FERNANDO; BERRETA MARCELO; CLADERA JORGE LUIS; LANZAVECCHIA SILVIA BEATRIZ

Panamá

Congreso; 8vo Congreso Hemisférico de la mosca de la fruta; 2012

Dirección Nacional de Sanidad Vegetal del MIDA, el Organismo Internacional Regional de Sanidad Agropecuaria (OIRSA), el Programa Centroamericano de Maestría en Entomología de la Universidad de Panamá y USDA.

Wolbachia pipiens (Alphaproteobacteria: Rickettsiales) are maternally inherited endosymbionts associated to reproductive tissues of many arthropod species. Its presence produces alterations in their hosts, including cytoplasmic incompatibility, parthenogenesis induction, males death and males feminization. It is also involved in multiple physiological processes such as, iron metabolism, insulin signaling and immune response. In the artificial rearing of the parasitoid Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae) the immune response of the host organism (fruit flies) against the parasitation event plays a key role in the host-parasitoid interaction. This interaction is influenced by the presence of microorganisms such as Wolbachia. In the present work we assessed the presence of Wolbachia pipiens in laboratory populations of D. longicaudata and in its host Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) by PCR (Polymerase Chain Reaction) and sequencing techniques. Seven loci (16S rDNA; Wsp; GatB; HcpA; ftsZ; CoxA and FbpA) were targeted with specific primer pairs. The sequences of the amplified products were compared with those available in Wolbachia database. Only in the case of A. fraterculus, Wolbachia-specific sequences for all loci were obtained. The absence of specific PCR products in D. longicaudata presupposes the absence of infection. Phylogenetic analysis of the Wolbachia sequences obtained from A. fraterculus clustered the bacterium strain within the clade A - group WmelA. In order to determine the influence of this bacterium in the interaction A. fraterculus: D. longicaudata, we investigated the effectiveness of antibiotic treatments of A. fraterculus larvae to clean Wolbachia and we used this material to perform a preliminary study of parasitism rate by D. longicaudata. Different concentrations (0.01; 0.1; 0.2 and 0.03 %) of rifampicin and tetracycline were evaluated in larval diet and percentage of adult emergence was registered. The persistence of Wolbachia was assessed by PCR (16SrDNA and Wsp). Both antibiotic treatments were equally effective in cleaning Wolbachia at the lowest concentration tested, without affecting the rate of adults recovery. Parasitism rate analysis is in progress. We discuss the results obtained in the context of the host-parasitoid interactions, D. longicaudata artificial rearing productivity and the utility of Wolbachia-free lines of A. fraterculus.