Reproductive system and fitness of Vriesea friburgensis, a self‐sterile bromeliad species

Abstract

Reproductive biology and plant fertility are directly related to many aspects of plant evolution and conservation biology. Vriesea friburgensis is an epiphytic and terrestrial bromeliad endemic to the Brazilian Atlantic rainforest. Hand‐pollination experiments were used to examine the reproductive system in a wild population of V. friburgensis. Plant fertility was assigned considering flower production, fruit and seed set, seed germination, and pollen viability. Self‐sterility observed from spontaneous selfing and manual self‐pollination treatments may be the consequence of late‐acting self‐incompatibility. Hand‐pollination results indicated no pollen limitation in the population studied. Floral biology features such as a few daily open flowers, nectar production, and sugar concentration corroborate hummingbirds as effective pollinators, although bees were also documented as pollinators. Components of fitness such as high flower, fruit, and seed production together with high seed and pollen viability indicate that this wild population is viable. From a conservation point of view, we highlight that this self‐sterile species depends on pollinator services to maintain its population fitness and viability through cross‐pollination. Currently, pollinators are not limited in this population of V. friburgensis. Conversely, the maintenance and continuous conservation of this community is essential for preserving this plant–pollinator mutualism.

Floral and reproductive biology of Alcantarea nahoumii (Bromeliaceae), a vulnerable endemic species of the Atlantic Forest

“…Inbreeding depression can occur with manual selfpollination, as reported by Vaughton et al (2010) for the species Cyrtanthus breviflorus and by Paggi et al (2013) for Vriesea friburgensis, although no studies have been carried out to evaluate the endogamic effects on the progeny of A. nahoumii. On the other hand, cross-pollination and/or open pollination promote gene flow between individuals, which can increase the genetic variability within and between populations, both of which are important features for diversification and maintenance of species (Vosgueritchian & Buzato 2006).…”

“…Allogamy and self-compatibility are present in the majority of species (Wendt et al 2001;2008;Matallana et al 2010;2016), but there are also records of agamospermy, autogamy, and selfincompatibility (Martinelli 1994;Scrok & Varassin 2011;Paggi et al 2013;Souza et al 2017). Studies of the floral and reproductive biology of A. nahoumii are important for formulating management and conservation programs, especially since this species is subjected to pressures from habitat fragmentation, including shortages of specific pollinators and reduced population sizes, which can lead to pollen limitation.…”

Are breeding system and florivory associated with the abundance ofTillandsiaspecies (Bromeliaceae)?

“…Flowering phenology can both influence and be influenced by pollinators and florivores. Studies regarding the community of hummingbird‐pollinated plants (which includes many Bromeliaceae) have shown that flowering periods of sympatric species are predictable, occur at different times throughout the year and present synchronous flowering; in addition, each individual produces few flowers every day with each flower producing a small quantity of high‐quality nectar (Canela & Sazima, ; Matallana et al ., ; Paggi et al ., ). These characteristics have been interpreted as a strategy to maintain the population of shared pollinators throughout the year, whereas differences in flower size between species have been proposed as a strategy to avoid hybridization (Kodric‐Brown et al ., ; Ackerman, Rodríguez‐Robles & Meléndez, ; Matallana et al ., ).…”

“…Experimental studies conducted in 88 species of bromeliads showed that 66% are self‐compatible (58 species), 8% are self‐compatible but pollinator dependent and 25% are self‐incompatible. Among the 58 self‐compatible species, 36 species have a high proportion of fruit set produced by autonomous self‐fertilization (Bush & Beach, ; Aizen & Feinsinger, ; Canela & Sazima, ; Lasso & Ackerman, , ; Ramírez‐Morillo, Fernández‐Concha & May, ; Cascante‐Marin et al ., , ; Ramírez‐Morillo et al ., ; Cascante‐Marín, Wolf & Oostermeijer, ; Matallana et al ., ; Kamke et al ., ; Paggi et al ., ; Mondragón, Valverde & Hernández‐Apolinar, ). Studies describing the breeding system of a community of epiphytes are scarce (Bush & Beach, ; Matallana et al ., ), making it possible that the overall pattern of the distribution of breeding systems among bromeliads could be biased towards self‐compatible species.…”

Seed morphology of Vriesea friburgensis var. paludosa L.B. Sm. (Bromeliaceae)

“…It is found in Brazil's southern, southeastern and northeastern regions, from Rio Grande do Sul to Pernambuco States (Martinelli et al 2008), occurring in the Atlantic Forest (Stehmann et al 2009) (figure 1a). However, wild populations of V. friburgensis have been reduced by recent destruction and fragmentation of its natural habitat due to human disturbance as well as illegal collections (Paggi et al 2013). According to Martinelli et al (2008), the conservation status of Vriesea friburgensis is endangered and vulnerable.…”