Patterns of introduction and diversification of Vanilla planifolia (Orchidaceae) in Reunion Island (Indian Ocean)

Abstract

The cultivated species Vanilla planifolia is a typical example of a crop introduced from its area of origin (America) to new regions where natural pollinators are absent. Although the Vanilla cultivars are exclusively vegetatively propagated, a high degree of phenotypic variation is observed among the cultivars in their introduction areas such as Reunion Island. To test several hypotheses explaining this variation-different introduction events, somatic mutations and sexual reproduction (through manual pollination)-we used AFLP markers to elucidate the patterns of introduction of V. planifolia. Most of the accessions cultivated in the world were derived from a single accession, possibly the Mexican cultivar Mansa. The patterns of diversification of this cultivated species were also studied and compared with other cultivated (V. tahitensis) and wild (V. pompona and V. bahiana) species. Except for one particular phenotype ('Aiguille'), which may come from sexual reproduction, cultivated accessions exhibit very low levels of genetic diversity. They have evolved by the accumulation of point mutations through vegetative multiplication. The genetic diversity revealed could not explain the phenotypic diversity, which may be related to epigenetics or polyploidy. This new understanding of the basis of genetic diversity of vanilla may assist to improve management of genetic resources.

Caracterización estomática de cinco especies del género Vanilla.

“…V. planifolia G. Jackson, la especie más cultivada, presentó valores intermedios de LE, AE de 41,864 y 31,682 µm, respectivamente, en la parte abaxial de la hoja. V. insignis Ames y V. odorata Presl fueron las que presentaron estomas más grandes en la parte adaxial de la hoja, estos resultados coinciden con lo registrado por Bory et al (2008) ). NEE= Número de estomas por el envés.…”

“…V. planifolia G. Jackson es la especie más importante por sus características aromáticas y demanda en la industria alimentaria, debido a que el 95% de la producción mundial proviene de esta especie (Bory et al, 2008).…”

“…Bory et al (2008), trabajaron en la diversificación de Vanilla planifolia G. Jackson (Orchidaceae) en Isla Reunión, donde clasificaron a los estomas según su tamaño. En México donde se considera centro de origen de V. planifolia G. Jackson no se reportan trabajos relacionados con estomas.…”

A new vanilla species from Costa Rica closely related to V. planifolia (Orchidaceae)

“…Morphologically, the VanL plants showed most similarity with V. planifolia and V. ×tahitensis, a species having a hybrid origin involving V. planifolia and V. odorata (Lubinsky et al 2008). However, compared to these two species VanL plants had much smaller leaves, flowers and fruits (Fig.…”

Colombian vanilla and its microbiota. III. Diversity and structure of the endophytic community

“…Vanillas are the only edible orchids known to date, and about a hundred species are currently accepted (Soto-Arenas and Cribb 2010). Vanilla planifolia is an important aromatic crop that is propagated asexually, so its genetic base is narrow and it is prone to devastating infections by pathogenic microorganisms (Bory et al 2008, Gamboa-Gaitán 2014, Ordóñez et al 2012. Studying naturally-associated endosymbionts of Vanilla is important since endophytes have been broadly proposed as potential antagonists of disease-causing microorganisms, so they can play an important role in plant defence and biological control (Herre et al 2007, Mejía et al 2008, Otero et al 2013.…”