Abstract

Caryedon serratus, groundnut seed-beetle, is a major pest of groundnut (Arachis hypogaea).Structuring of its biotype is subservient to the host plant that has already been established, whiledifferences in the life history and ecology of the populations have led to the study of their genetic relationship, although a potential structure of these populations is seen in different biotypes. The aim of this work is to identify the different haplotypes circulated in the West African sub-region and to assess the phylogenetic affinities between ecological populations of C. serratus. Molecular marker and DNA sequences were used to assess genetic diversity and population structure of C. serratus on the West of Africa. Sequences analysis of mitochondrial (Cytb) and ribosomal (28S) DNA and the phylogenetic reconstructions by parsimony and maximum likelihood assigned the presence of haplogroup withmaintained gene flow between the sampled populations. The result shows that genetic distance is not significant between localities, even if it appears that the variability which is quite strong and peculiar are retained for populations of Niger and the Senegal-Gambia border. Geographical isolation effect on population genetic structure tested with correlation test confirms this result.

Key words: Caryedon serratus, DNA sequences Cyt b, 28S, haplotype, groundnut, West Africa.