Ramirez 2015 (Conference Paper) Mexico, Tillandsia

Reproductive biology in Mexican Tillandsias

Author(s):—I.M. Ramírez M. & D. Mondragón in Benko-Iseppon, A.M.; Alves, M. & Louzada, R. (2015) An overview and abstracts of the First World Congress on Bromeliaceae Evolution. Rodriguésia 66(2): A1-A66.

Publication:— (2015).

Abstract:—Genus Tillandsia L. is the largest bromeliaceous genus in the family with ca. 622 species (representing ca. 19% of the family). In Mexico, Tillandsia is also the largest bromeliaceous genus with ca. 175 species (53% of ca. 400 species reported in the country). Most of the species of Mexican Tillandsia belong to subgenus Tillandsia and few to subgenera Allardtia, Diaphoranthema, Pseudoalcantarea, and Pseudo-catopsis. Speciesin the subgenus Tillandsia are characterized by their epiphytic habit, inflorescences mainly racemes, odorless flowers with diurnal anthesis, tubular corollas, these lilac, yellow, purple or blue, with stamens and stigma exerted, and abundant nectar, suggesting xenogamy and pollination by hummingbirds. Tillandsia is one of the most important genera in horticulture in the world. We have data (from literature and our own) on breeding systems for more than 20 Tillandsia species native to Mexico, that show that even though floral morphology suggests xenogamy, based on fruit and seed production from experimental crosses, more breeding systems could be operating in nature. Breeding systems range from agamospermy (e.g. T. prodigiosa), self-incompatibility and pollinator dependent (T. streptophylla) to species with combined potential breeding systems such as selfing, unassisted pollination, and cross-pollination (T. dasyliriifolia). In order to know what breeding system(s) is (are) operating in self-compatible species, further genetic analysis should be performed as floral morphology and results on experimental crosses do not always support predictions. Examples on studies that integrate information from different fields on Mexican Tillandsia show that other factors besides breeding system play a more important role in the genetic composition of populations, such as seed dispersal distance (in T. elongata var. subimbricata), and clonal propagation (in T. brachycaulos).

Keywords:—Breeding System; Tillandsia; Genetics.