Investigating mating system of white pine weevil, Pissodes strobi (Coleoptera: Curculionaidae) using microsatellite DNA markers

• Main Author: Liewlaksaneeyanawin, Cherdsak
• Format: Others
• Language: English
• Published: 2009
• Online Access: http://hdl.handle.net/2429/11372

White pine weevil is one of the most destructive and economically important forest pests in British Columbia because it causes damage to natural forest and plantation. The mating system, which is essential information for assessing possibility of sterile insect release programs and determining genetic diversity of insect populations, was studied from breeding experiments with varying number of females and males. Four polymorphic microsatellite markers were used for the mating system analysis. All microsatellite loci segregated in a Mendenlian fashion. The results of 1 Female: 2 Males mating showed that sperm precedence occurs in 82% of the studied replications. The 1 Female: 4 Males mating revealed not only mixed paternity, but supported the occurrences of sperm precedence as well. In this experiment, female weevils mated to four different males had a mean paternity of 2.8. The existences of sperm mixing were observed in both 1 Female: 2 Males and 1 Female: 4 Males matings. In addition, the possibility of sperm depletion was also observed in both of the 2 Females: 1 Male and 4 Females: 1 Male matings. The evidences of sperm precedence and multiple paternity will influence the style of "the Integrated Pest Management". Sperm precedence has important implications on the ability of sterile insect techniques. Also, the incidence of multiple paternity seems likely to affect the long-term outcome of tree breeding program via the adaptation of white pine weevils to overcome resistant trees. === Forestry, Faculty of === Graduate