Author
FRANKS, STEVE - Fordham University | |
Pratt, Paul | |
TSUTSUI, NEIL - University Of California |
Submitted to: Conservation Genetics
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 8/27/2010 Publication Date: 9/12/2010 Citation: Franks, S., Pratt, P.D., Tsutsui, N. 2011. Direct evaluation of a genetic bottleneck in a recently introduced biological control insect. Biological Control. 12(1):201-211. Interpretive Summary: We examined phylogeography and population genetics of the melaleuca psyllid Boreioglycaspis melaleucae, which was introduced from Australia to Florida as a biological control agent of the invasive plant Melaleuca quinquenervia. We sampled psyllids in the native and introduced ranges as well as individuals stored from the original founding population. This allowed us to examine the bottleneck directly by sampling the individuals that actually were the bottleneck. There were only 2 mtDNA haplotypes found in the introduced range compared to 7 in the native range, consistent with a loss of genetic diversity following a bottleneck. The haplotypes found in the introduced range were also found in the quarantine populations. Overall there was strong evidence of a population bottleneck, particularly from the mtDNA data. For biological control introductions to be successful, it may be important to collect from widespread locations in the native range even when there is low genetic structure in order to avoid the loss of rare alleles and to maintain the potential for evolution following introduction. Technical Abstract: We examined phylogeography and population genetics of the melaleuca psyllid Boreioglycaspis melaleucae, which was introduced from Australia to Florida as a biological control agent of the invasive plant Melaleuca quinquenervia. We sampled psyllids in the native and introduced ranges as well as individuals stored from the original founding population. This allowed us to examine the bottleneck directly by sampling the individuals that actually were the bottleneck. We used mtDNA sequence data and 4 variable microsatellite loci (SSRs). The mtDNA haplotypes showed a clear geographic cline in the native range and were congruent with the known introduction history. There were only 2 mtDNA haplotypes found in the introduced range compared to 7 in the native range, consistent with a loss of genetic diversity following a bottleneck. The haplotypes found in the introduced range were also found in the quarantine populations. Assignment tests using microsatellite data grouped together individuals from several native populations, and revealed a distinct quarantine collection. However, there was relatively low genetic structure in the native and introduced ranges, and hierarchical ANOVA showed that only 0.7% of genetic variation was among source locations. Overall there was strong evidence of a population bottleneck, particularly from the mtDNA data. For biological control introductions to be successful, it may be important to collect from widespread locations in the native range even when there is low genetic structure in order to avoid the loss of rare alleles and to maintain the potential for evolution following introduction. |