Pollination of Campomanesia phaea (Myrtaceae) by night‐active bees: a new nocturnal pollination system mediated by floral scent

Abstract

Bees are the most important diurnal pollinators of angiosperms. In several groups of bees a nocturnal/crepuscular habit developed, yet little is known about their role in pollination and whether some plants are adapted specifically to these bees. We used a multidisciplinary approach to investigate the reproductive biology and to understand the role of nocturnal/crepuscular bees in pollination of Campomanesia phaea (Myrtaceae), popularly named cambuci. We studied the floral biology and breeding system of C. phaea. We collected the floral visitors and tested the pollinators' effectiveness. We also determined the floral scents released at night and during daytime, and studied behavioural responses of crepuscular/nocturnal bees towards these scents. The flowers of cambuci were self-incompatible and had pollen as the only resource for flower visitors. Anthesis lasted around 14 h, beginning at 04:30 h at night. The flowers released 14 volatile compounds, mainly aliphatic and aromatic compounds. We collected 52 species of floral visitors, mainly bees. Nocturnal and crepuscular bees (four species) were among the most frequent species and the only effective pollinators. In field bioassays performed at night, nocturnal/crepuscular bees were attracted by a synthetic scent blend consisting of the six most abundant compounds. This study describes the first scent-mediated pollination system between a plant and its nocturnal bee pollinators. Further, C. phaea has several floral traits that do not allow classification into other nocturnal pollination syndromes (e.g. pollinator attraction already before sunrise, with pollen as the only reward), instead it is a plant specifically adapted to nocturnal bees.

Is Nocturnal Foraging in a Tropical Bee an Escape From Interference Competition?

“…Ours is the first study of Megalopta to analyze data minute by minute and separate observations by flower to explicitly test for overlap, although studies of other Megalopta species show results similar to our Fig. 2 (Franco and Gimenes 2011, Krug et al 2015, Oliveria et al 2016, Cordeiro et al 2016). …”

“…Because flowers produced little nectar after midnight (Kays et al 2012), it is unsurprising that overall visitation rates were low in the morning. Other species of flowers that open late at night are visited by Megalopta more frequently in the pre-dawn foraging period (Roulston 1997, Franco and Gimenes 2011, Smith et al 2012, Krug et al 2015, Oliveria et al 2016, Cordeiro et al 2016). …”

“…Megalopta (Halictidae) are solitary or weakly social (typically 2–3 colony members) bees that forage from both diurnal flowers that remain open past sunset or open before sunrise, and flowers with nocturnal anthesis (Janzen 1968, Roulston 1997, Hopkins et al 2000, Wcislo et al 2004, Kelber et al 2005, Franco and Gimenes 2011, Smith et al 2012, Krug et al 2015, Oliveria et al 2016, Cordeiro et al 2016). Megalopta are generalist foragers, with 64 species of pollen recorded from nests at a single site, an active nesting season of ∼9 months and opportunistic shifts among pollen sources based on availability (Smith et al 2012).…”

Interpopulation variation in pollinators and floral scent of the lady’s-slipper orchid Cypripedium calceolus L.

“…Olfactory cues are most important for plants pollinated at night (Cordeiro et al 2017;Dobson 2006;Dötterl et al 2012), and for highly specialized pollination systems (Heiduk et al 2016;Milet-Pinheiro et al 2013;Schäffler et al 2015;Schiestl et al 1999).…”

Como as Abelhas Percebem as Flores E Por Que Isto É Importante?

“…O significado ecológico dessas adaptações ainda é discutido, mas certamente elas podem conferir vantagens, como a obtenção de maiores quantidades de recursos florais em horários onde a competição seria baixa , Kelber et al 2005. Para as plantas, a vantagem seria a visita exclusiva de polinizadores, sem a inter-ferência de outros visitantes ( Hopkins et al 2000, Cordeiro et al 2016, Soares & Morellato 2017.…”