Scientia Horticulturae 212 (2016) 240–250 Contents lists available at ScienceDirect Scientia Horticulturae journal homepage: www.elsevier.com/locate/scihorti Molecular and microclimatic characterization of two plantations of Vanilla planifolia (Jacks ex Andrews) with divergent backgrounds of premature fruit abortion Verónica Borbolla Pérez a , Lourdes Georgina Iglesias Andreu a,∗ , Eder Alan Escalante Manzano b , Jaime Martínez Castillo b , Matilde Margarita Ortiz García b , Pablo Octavio Aguilar c a Instituto de Biotecnología y Ecología Aplicada (INBIOTECA) de la Universidad Veracruzana (UV), Campus para la Cultura, las Artes y el Deporte, Av. de las Culturas Veracruzanas No. 101, Col. Emiliano Zapata, C.P. 91090, Jalapa, Veracruz, Mexico b Laboratorio de Marcadores Moleculares de la Unidad de Recursos Naturales del Centro de Investigación Científica de Yucatán, A.C. (CICY), Calle 43, Col. Chuburná de Hidalgo, C.P. 97200, Mérida, Yucatán, Mexico c Centro de Investigaciones Biológicas (CIB), Universidad Autónoma del Estado de Hidalgo (UAEH), Ciudad del Conocimiento, Carretera Pachuca-Tulancingo Km.4.5, Col. Carboneras, C.P. 42184, Mineral de la Reforma, Hidalgo, Mexico a r t i c l e i n f o Article history: Received 27 April 2016 Received in revised form 27 September 2016 Accepted 3 October 2016 Keywords: Heterozygosis Environment-dependent inbreeding depression Genetic diversity and structure SSR ISSR a b s t r a c t In order to elucidate the influence of genetic diversity and microclimatic conditions on Premature Fruit Abortion (PFA) in this study was performed the molecular and microclimatic characterization of two V. planifolia plantations with divergent backgrounds of PFA. The genetic diversity was investigated using microsatellite markers (SSR) and intergenic simple sequence repeats (ISSR) markers. The SSR markers were highly monomorphic and therefore were used only as a reference point to indicate the level of heterozygosity from codominant markers. In contrast, the level of resolution of the ISSR markers in this study was sufficient to distinguish individual differences between the plantations. Overall, the entire analysis performed in this study with ISSR markers pointed to a higher genetic diversity in the El Palmar plantation, which interestingly, does not show evidence of PFA. In this regard, the number of private loci, Shannon’s diversity index and the expected heterozygosity estimates were higher for El Palmar than for Calle Grande. These results are consistent with the information generated by the AMOVA and UPGMA analysis. In addition, the low levels of heterozygocity detected with both markers suggest the likelihood that the V. planifolia are showing a reduction in their adaptive capacity due to inbreeding depression processes. Moreover, the records of environmental conditions in recent years showed that during the periods when the PFA had worsened, the environmental temperatures reached up to 45 ◦ C. Finally, our results of correlation analysis pointed out that a low genetic diversity and high environmental temperatures were significantly associated with PFA. © 2016 Elsevier B.V. All rights reserved. 1. Introduction The genus Vanilla Plumier ex Miller belongs to a basal lineage of the orchid family (Soto-Arenas, 1999). Within this genus, Vanilla planifolia Jacks ex Andrews is the most valued species because ∗ Corresponding author. E-mail addresses: veronicabor1@hotmail.com (V. Borbolla Pérez), liglesias@uv.mx, liauv2016@outlook.com (L.G. Iglesias Andreu), alancin82@hotmail.com (E.A. Escalante Manzano), jmartinez@cicy.mx (J. Martínez Castillo), ortiz.matilde@gmail.com (M.M. Ortiz García), aguilpo@yahoo.com.mx (P. Octavio Aguilar). natural vanillin is extracted from its fruit (Kanisawa et al., 1994). Currently, vanilla is regarded as the world’s second most expensive spice (Divakaran et al., 2008). In recent years, the natural habitat of V. planifolia has been severely fragmented, and the conservation of this species is critical. Wild V. planifolia individuals are extremely rare, and no wild populations deemed healthy in demographic or genetic terms have been reported (Soto-Arenas, 1999). Hence, V. planifolia is considered a species with a high degree of genetic ero- sion and is officially subject to special protection (Pr) under the Mexican standard NOM-059-SEMARNAT-2010 (SEMARNAT, 2010). To date, the largest source of available V. planifolia germplasm comes from commercial plantations that show complex and diverse issues (Bory et al., 2008a). However, despite its impor- http://dx.doi.org/10.1016/j.scienta.2016.10.002 0304-4238/© 2016 Elsevier B.V. All rights reserved.