title: Complementary sex determination in the parasitic wasp Diachasmimorpha longicaudata.
abstract: We studied the sex determination in Diachasmimorpha longicaudata, a parasitoid braconid wasp widely used as biological control agent of fruit pest tephritid flies. We tested the complementary sex determination hypothesis (CSD) known in at least 60 species of Hymenoptera. According to CSD, male or female development depends on the allelic composition of one sex locus (single-locus CSD) or multiple sex loci (multiple-locus CSD). Hemizygote individuals are normal haploid males, and heterozygotes for at least one sex locus are normal diploid females, but homozygotes for all the sex loci are diploid males. In order to force the occurrence of diploid males in D. longicaudata, we established highly inbred lines and examined their offspring using chromosome counting, flow cytometry, and sex ratio analysis. We found that when mother-son crosses were studied, this wasp produced about 20% of diploid males out of the total male progeny. Our results suggest that this parasitoid may represent the second genus with multiple-locus CSD in Hymenoptera. Knowledge about the sex determination system in D. longicaudata is relevant for the improvement of mass rearing protocols of this species. This information also provides the necessary background for further investigations on the underlying molecular mechanisms of sex determination in this species, and a better insight into the evolution of this pathway in Hymenoptera in particular and insects in general.
authors: Institute of Entomology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Czech Republic; Instituto de Genética "Ewald A Favret," Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina.
authors: Leonela
authors: L
authors: Carabajal Paladino
authors: Instituto de Genética "Ewald A Favret," Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina.
authors: Irina
authors: I
authors: Muntaabski
authors: Instituto de Genética "Ewald A Favret," Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina.
authors: Silvia
authors: S
authors: Lanzavecchia
authors: Department of Botany, University of South Bohemia, Ceske Budejovice, Czech Republic.
authors: Yoann
authors: Y
authors: Le Bagousse-Pinguet
authors: Instituto de Microbiología y Zoología Agrícola, Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina.
authors: Mariana
authors: M
authors: Viscarret
authors: Instituto de Genética "Ewald A Favret," Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina.
authors: Marianela
authors: M
authors: Juri
authors: Instituto de Ecología y Desarrollo Sustentable, Universidad Nacional de Luján, Luján, Argentina.
authors: Luciana
authors: L
authors: Fueyo-Sánchez
authors: Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina; Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina.
authors: Alba
authors: A
authors: Papeschi
authors: Instituto de Genética "Ewald A Favret," Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina.
authors: Jorge
authors: J
authors: Cladera
authors: Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina; Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina; Instituto de Ecología, Genética y Evolución de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina.
authors: María José
authors: MJ
authors: Bressa
mesh_terms: D000483:Alleles; D000818:Animals; D005075:Biological Evolution; D004171:Diploidy; D005260:Female; D006238:Haploidy; D008297:Male; D019849:Sex Determination Processes / Q000235:genetics*; D012744:Sex Ratio; D014863:Wasps / Q000235:genetics* / Q000502:physiology