|De Leon, Jesus|
|SETAMOU, MAMOUDOU - Citrus Center|
|GASTAMINZA, GERARDO - Estacion Experimental Agroindustrial Obispo Colombres (EEAOC)|
|BUENAHORA, JOSE - National Agricultural Research Institute(INIA)|
|WLOSEKSTANGRET, CARLOS - Collaborator|
|YAMAMOTO, PEDRO - Fundecitrus - Brazil|
|LOGARZO, GUILLERMO - South American Biological Control Lab(SABCL)|
Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 5/2/2010
Publication Date: 6/2/2010
Citation: De Leon, J.H., Setamou, M., Gastaminza, G.A., Buenahora, J., Wlosekstangret, C.R., Yamamoto, P.T., Logarzo, G. 2010. Two founding events identified in Asian citrus psyllid populations collected in the Americas, pp. 51-58. In: VI Congreso Argentino de Citricultura, 2-4 June 2010, San Miguel de Tucuman, Tucuman, Argentina.
Interpretive Summary: A genetic analysis of Asian citrus pysllid (ACP) populations collected in the American continent was undertaken with eight populations from South America and 14 populations from North America for a total of 121 individuals. A portion of the mitochondrial COI gene was sequenced in order to determine the number of founding events or invasions in the American continent. The results uncovered COI variation as 19 haplotypes (hp) were identified in the populations. The haplotypes, however, fell into two groups, hp1-8 were identified in populations from South America (Group 1), whereas, hp9-19 were identified in populations from North America (Group 2). Sharing of haplotypes was not observed between the two groups, indicating haplotype structure. Haplotypes 1 and 9 were present in the highest frequencies within each population and within their respective groups, suggesting that the ancestral or founding haplotypes were identified within each group. Analyses of the evolutionary relationships among haplotypes using two phylogenetic network programs distinguished the two groups, while identifying hp1 and 9 as the ancestral or founding haplotypes within their respective groups. The data highly suggest that two founding events of ACP populations occurred in the American continent, one in South America and one in North America. This information is important because ACP has been in Brasil for 70 years and the data suggests that ACP did not invade North America from South America, but rather, each sub-continent was probably invaded by a different Asian country. The practical use of this information is that the source for collection of natural enemies for ACP may be different for each sub-continent.
Technical Abstract: A phylogeographic analysis inferred from the partial mitochondrial cytochrome oxidase subunit I gene (COI) (433-bp) was performed with 22 populations (n=121) of Diaphorina citri collected in the Americas. Eight populations (n=46) from four countries in South America and 14 populations (n=75) from four countries in North American were analyzed. Haplotype variation was uncovered as 19 haplotypes were identified. The haplotypes fell into two groups, hp1-8 were identified in populations from South America (Group 1) and hp9-19 were identified in populations from North America (Group 2). Hp1 and 9 were present in the highest frequencies within each population and within their groups, 84-85% in both sub-continents. Sharing of haplotypes was not observed between the two groups. A change in nucleotide (#48) in 100% of individuals within each group allowed for their discrimination, ‘G’ in Group 1 and ‘A’ in Group 2. An analysis of molecular variance uncovered significant genetic structure (FCT=0.73308; P=0.000) between the two groups. A phylogenetic analysis of the haplotypes distinguished the two groups as each clustered into separate clades in a parsimonious phylogram with strong bootstrap support. Evolutionary analyses were performed with two intra-specific phylogenetic network programs. ParsimonySplits and Statistical Parsimony networks discriminated the two groups, while hp1 and 9 were identified as the ancestral or founding haplotypes within their respective group. The current data suggest that two founding events of D. citri occurred in the Americas, one in South America and one in North America.