|
|
||||||||
Brief Communication |
2 Department of Botany and Plant Sciences, University of California, Riverside, California 92521-0124 USA 3 Wisconsin State Herbarium, Department of Botany, University of Wisconsin, Madison, Wisconsin 53706-1381 USA 4 Departamento de Biología y Geología (Area de Biodiversidad y Conservación), ESCET, URJC 28939 Madrid, Móstoles, Spain 5 Département Recherche et Développement, Etablissement Vanille de Tahiti, Raiatea BP 912-98735, French Polynesia 6 Centro de Investigaciones Tropicales, Universidad Veracruzana, Xalapa, Veracruz 91019 Mexico
ABSTRACT
Absent in the wild, Tahitian vanilla (V. tahitensis) is a gourmet spice restricted in distribution to cultivated and feral stands in French Polynesia and Papua New Guinea. Its origins have been elusive. Our objective was to test the purported hybrid derivation and parentage of V. tahitensis from aromatic, neotropical progenitors. Nucleotide sequences from V. tahitensis and neotropical Vanilla were assayed for phylogenetic relatedness in two independently inherited genomic regions, the nuclear ITS region, and the trnH-psbA noncoding region of chloroplast DNA. As predicted to occur for early generation hybrids, placement of V. tahitensis was nonconcordant. All V. tahitensis clustered with V. planifolia from analysis of cpDNA sequences, suggesting V. planifolia as the maternal genome contributor. Phylogenetic reconstruction of ITS sequences showed that most V. tahitensis nested incongruently with V. odorata, but others remained sister to V. planifolia. Recovery of ITS clones in V. tahitensis related to both V. planifolia and V. odorata also supports its biphyletic origin from these two taxa. We interpret the high percentage (95%) of additive polymorphic sites in V. tahitensis relative to its parents as indication of a recent, and probably human-mediated, evolutionary origin.
Key Words: crop origins French Polynesia hybridization Mesoamerica Orchidaceae Tahitian vanilla Vanilla
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |