Reproductive biology and pollination of Aechmea distichantha Lem. (Bromeliaceae)

Abstract

ABSTRACT(Reproductive biology and pollination of Aechmea distichantha Lem. (Bromeliaceae)). Reproductive biology, including phenology, fl ower biology, pollination, and the reproductive system in the bromeliad Aechmea distichantha were studied in an Araucaria forest in the state of Paraná. Phenology and reproduction in terricolous plants were followed in October 2006 and May -October of 2007. Flowering peaked from June to September and fruiting was from June to October. Flower anthesis lasted one day. Flowers were pollinated the most by the hummingbird Stephanoxis lalandi and the most common butterfl y visitor was Lychnuchoides ozias ozias. Nectar concentration declined during anthesis, while nectar volume was constant. Aechmea distichantha is self-compatible with 30-45% fruit formation in self-pollination tests. Sunlight infl uences reproduction: when controlling for bromeliad and infl orescence size, plants in sunlight produced more seeds per fruit than plants in the shade. Reproduction was also associated with infl orescence size when controlling for bromeliad size. Th at is, larger infl orescences in similar sized plants produced more fl owers and more seeds per fruit.

Effect of rosette size, clonality and spatial distribution on the reproduction of Vriesea carinata (Bromeliaceae) in the Atlantic Forest of Paraná, southern Brazil

“…Even small variation in tree crowns due to light availability may change the number of flowers produced by a plant (Maia et al 2013). Indeed, Aechmea distichantha bromeliads growing under sunny conditions had a larger reproductive effort than those in shaded conditions, when controlled for bromeliad size (Scrok & Varassin 2011). It is also possible that aggregated individuals are genetically more closely related (Lovett-Dust 1981;Izquierdo & Piñero 1998;Canela & Sazima 2003;Jacquemyn & Honnay 2008) and thus have the same reproductive potential.…”

“…In bromeliads, the spatial distribution of plants affects their sexual reproductive success (Scrok & Varassin 2011). The spatial distribution of bromeliads can be influenced by the local environment, including such factors as the presence of suitable substrate, light, temperature and humidity (Cogliatti-Carvalho et al 2001).…”

“…These environmental features are often spatially structured (Cottenie 2005) and may influence plant reproduction in a complex way. For example, neighboring individuals may compete for pollinators (Grindeland et al 2005;Brys & Jacquemyn 2010), and so changes in fecundity may be related to variation in spatial arrangement (Aarssen & Taylor 1992;Scrok & Varassin 2011). Furthermore, the balance between clonal and sexual growth in clonal plants may change according to microenvironmental heterogeneity (Coelho et al 2008a;Izquierdo & Piñero 1998).…”

“…These traits are associated with an epiphytic habitat and include: 1) sexual reproduction coupled with bird-pollination (mostly hummingbirds) and 2) presence of "entangling seeds" (i.e., those able to attach to a host), such as wind-dispersed comose seeds or animaldispersed seeds from fleshy fruits. Vriesea is the third largest bromeliad genus with approximately 280 species (Costa et al 2015), which have monocarpic and clonal reproduction via axillary buds in the basal leaf sheaths (Costa et al 2014), and are mostly pollinated by hummingbirds (Araújo et al 1994;Sazima et al 1995a;1996;Martinelli 1997;Machado & Semir 2006;Varassin & Sazima 2012), but also by bats (Sazima et al 1995b;1999;Martinelli 1997;Kaehler et al 2005), bees (Kaehler et al 2005) and butterflies (Scrok & Varassin 2011;Varassin & Sazima 2012). The comose seeds are dispersed by wind (Costa et al 2015).…”

Desenvolvimento floral e do óvulo e aspectos da reprodução em Aechmea sp. e Vriesea sp. (Bromeliaceae)

“…A nexina é composta pela endonexina e "foot Segundo Frankie et al (1983), atributos morfológicos e anatômicos da flor estão diretamente relacionados ao processo de polinização, podendo facilitar ou dificultar a ação dos visitantes seja pela associação entre o tamanho corporal dos animais e as dimensões florais, ou pela localização dos recursos na flor, sendo que quando essas características convergem, podem resultar no sucesso reprodutivo. Aliados aos estudos de caracterização morfoanatômica, aspectos da biologia floral relacionados ao processo de polinização, tais como variações morfológicas da flor, horário da antese, viabilidade e germinação de grão de pólen e receptividade do estigma, auxiliam na compreensão do processo reprodutivo permitindo a aplicação de práticas de manejo e melhoramento mais apropriadas (PARTON et al, 2002;VERVAEKE et al, 2003;LENZI;MATOS;ORTH, 2006;RIBEIRO, 2006;SILVA et al, 2006;SCROK;VARASSIN, 2011 BROWN, 1988;STAHL et al, 2012), horário da antese, receptividade do estigma, morfologia, viabilidade e germinação de grão de pólen (WEN; PARTON et al, 2002;VERVAEKE et al, 2003;SOARES et al, 2011) e a presença de recursos e atrativos florais relacionados aos polinizadores (BERNARDELLO; GALETTO; JULIANI, 1991).…”