Multiple paternity in a natural population of a wild tobacco fly, Bactrocera cacuminata (Diptera: Tephritidae), assessed by microsatellite DNA markers

Abstract

Mating frequency has important implications for patterns of sexual selection and sexual conflict and hence for issues such as speciation and the maintenance of genetic diversity. Knowledge of natural mating patterns can also lead to more effective control of pest tephritid species, in which suppression programmes, such as the sterile insect technique (SIT) are employed. Multiple mating by females may compromise the success of SIT. We investigated the level of polyandry and sperm utilization in a Brisbane field population of the tropical fruit fly, Bactrocera cacuminata (Hering), using seven polymorphic microsatellite loci. The offspring of 22 wild-caught gravid females were genotyped to determine the number of males siring each brood and paternity skew, using the programs gerud and scare. Our data showed that 22.7% of females produced offspring sired by at least two males. The mean number of mates per female was 1.72. Paternal contributions of double-sired broods were skewed with the most successful male having sired between 76.9% and 87.5% of the offspring. These results have implications for SIT, because the level of remating we have identified would indicate that wild females could mate with one or more resident fertile males.

Offspring genetic structure reveals mating and nest infestation behaviour of an invasive parasitic fly (Philornis downsi) of Galápagos birds

“…However, SIT may still be effective in suppressing populations of species in which females remate (e.g. melon fly: Steiner et al 1965), particularly if sterile males are released continuously (Song et al 2007). Proven to be a successful control method for agricultural pests (e.g.…”

“…An increased understanding of the reproductive behaviour of invasive insect parasites is central to the study of their population dynamics, life-history evolution and genetic structure, and may lead to more effective management strategies (Hendrichs et al 2002;Chevillon et al 2007;Song et al 2007). Genetic studies of parasitic, myiasis-causing flies have focused primarily on species of agricultural relevance, or have been mainly concerned with taxonomy and phylogenetics (Otranto and Stevens 2002;Azeredo-Espin and Lessinger 2006).…”

“…Two aspects of reproductive behaviour in parasitic insects that can be revealed through molecular techniques are female multiple mating and host infestation behaviour. Female multiple mating has implications for effective population size, rates of gene flow and maintaining genetic variation (Bonizzoni et al 2002;Song et al 2007). Oviposition behaviour in parasitic insects may vary with host density and distribution and determine parasite intensity and impact among hosts (Minkenberg et al 1992;Cronin and Strong 1999).…”

“…Highly variable molecular genetic markers (e.g. microsatellites) can uncover the occurrence of multiple mating and patterns of oviposition behaviour using offspring genotypes alone (Chapman et al 2003;Wang 2004;Song et al 2007;Zavodna et al 2007). Molecular genetic methods therefore offer the opportunity to examine withinhost genetic structure and mating behaviour of avian parasitic flies, while allowing the efficiency of control methods such as SIT to be assessed prior to, or in aid of, laboratory and field-based experiments (Bonizzoni et al 2002;Song et al 2007).…”

Potential Inbreeding in a Small Population of a Mass Flowering Species, <i>Xanthorrhoea johnsonii</i> (Xanthorrhoeaceae): Is Your Mother My Father?

“…AnAnalysis of the seedling radicals was used to identify the progeny genotypes. DNA extraction from all seedling tissue followed a modification of a Hair Lysis Extraction protocol [31]. Small amounts (2 -3 mm) of unfrozen seedling tissue were combined with 100 L of lysis ex-nealing temperatures were reduced by 2˚C -4˚C for some individuals.…”