Origen de las poblaciones del picudo del algodonero en Argentina, Brasil y Paraguay: una hipótesis basada en el estudio de genes mitocondriales

CONFALONIERI, VIVIANA A.; SCATAGLINI, MARIA A.; LANTERI, ANALÍA A.

Fortaleza, Brasil

Workshop; Cotton in the Southern Cone, Integrated Pest Management of the Cotton Boll Weevil in Argentina, Brazil and Paraguay - CFC-ICAC/04, Final International Workshop.; 2001

Project Integrated Pest Management of the Cotton Boll Weevil in Argentina, Brazil and Paraguay - CFC-ICAC/04,

Origen of boll weevil populations in Argentina, Brazil and Paraguay: a hypothesis based on two mitochondrial genes. The main goal of the present contribution is to test our previous hypothesis on the origin of boll weevil populations in Argentina, Brazil and Paraguay, based on RAPD technique, by means of a phylogeographic analysis, using sequences of the mitochondrial genes Cytochrome Oxidase I and II (COI and COII). Phylogeographic studies contribute to understand the evolutionary history of species and its geographic dispersal. One population is considered ancestral when it includes several haplotypes (variants of mitochondrial DNA) and as recent or colonizing, if it has one or few haplotypes. Our results indicate that populations from Tecomán (México) and Iguazú (Argentina) have the highest number of different haplotypes, seven in the former and five in the latter. This is typical of ancestral populations established since prehistoric times. In the remaining South American samples the number of haplotypes is lower than in México and Iguazú: four in Londrina (Brazil), two in Puerto Península (Argentina), one in Caacupé (Paraguay) and one in Laguna Naick Neck (Argentina). Among them, Londrina would be the population established for longer. The haplotype we have called “A” is present in all samples except those from Tecomán and Iguazú. Therefore, we interpret that South American populations with “A” haplotype are related to Texas sample, thus, with the “Southeastern form” of the boll weevil. On the contrary, the population from Iguazú, coming from a non-cotton growing area, it is genetically different and morphologically closer to the “mexican form”of  A. grandis.