title: LTR-retrotransposons Tnt1 and T135 markers reveal genetic diversity and evolutionary relationships of domesticated peppers.
abstract: Plant genetic resources often constitute the foundation of successful breeding programs. Pepper (Capsicum annuum L.) is one of the most economically important and diversely utilized Solanaceous crop species worldwide, but less studied compared to tomato and potato. We developed and used molecular markers based on two copia-type retrotransposons, Tnt1 and T135, in a set of Capsicum species and wild relatives from diverse geographical origins. Results showed that Tnt1 and T135 insertion polymorphisms are very useful for studying genetic diversity and relationships within and among pepper species. Clusters of accessions correspond to cultivar types based on fruit shape, pungency, geographic origin and pedigree. Genetic diversity values, normally reflective of past transposition activity and population dynamics, showed positive correlation with the average number of insertions per accession. Similar evolutionary relationships are observed to that inferred by previous karyosystematics studies. These observations support the possibility that retrotransposons have contributed to genome inflation during Capsicum evolution.
authors.affiliation: Laboratoire de Biologie Cellulaire, UR501, Institut Jean-Pierre Bourgin, INRA, 78026, Versailles Cedex, France.
authors.forename: Sheh May
authors.initials: SM
authors.lastname: Tam
authors.forename: Véronique
authors.initials: V
authors.lastname: Lefebvre
authors.forename: Alain
authors.initials: A
authors.lastname: Palloix
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Sage-Palloix
authors.forename: Corinne
authors.initials: C
authors.lastname: Mhiri
authors.forename: Marie-Angèle
authors.initials: MA
authors.lastname: Grandbastien
mesh_terms: D005075:Biological Evolution; D002212:Capsicum / Q000235:genetics*; D018556:Crops, Agricultural / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D014644:Genetic Variation; D018745:Genome, Plant; D018626:Retroelements; D013045:Species Specificity; D020079:Terminal Repeat Sequences / Q000235:genetics*
chemical_list: D018744:DNA, Plant; D018626:Retroelements