Floral scent in Annonaceae

Abstract

Many species of Annonaceae are known for their distinctive, penetrating floral aromas. Numerous pollination studies have documented floral scents which probably play a key role in specialized pollination strategies. In particular, floral scents appear to play crucial roles in deceptive pollination strategies, contributing to floral mimicry of ripe or decaying fruits, fungi and, potentially, carrion or faeces. Occasionally, floral scent may advertise genuine floral rewards, as is the case for two species of Unonopsis pollinated by male euglossine bees. To date, ten studies have chemically characterized floral scent for 24 species representing 11 genera of Annonaceae. In this review, I discuss the chemical composition and diversity of the analysed floral scents in Annonaceae. I also summarize and discuss a wide range of (human) perceptual descriptions of floral scent found throughout the literature on Annonaceae. I have framed discussions of floral scent in Annonaceae in ecological and evolutionary contexts whenever possible. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169, 262–279.

The reproductive biology of the early-divergent genus Anaxagorea (Annonaceae), and its significance for the evolutionary development of the family

“…e three other species, although not yet analyzed with respect to their scent compounds, also smell like fruits, which is a strong hint that they may also mimic fruit scents. e whole spectrum of oral scent compounds in Anaxagorea species, including minor compounds, is given by Goodrich (2012).…”

Evolutionary steps in the reproductive biology of Annonaceae

“…On the other hand, the melittophilous Unonopsis stipitata attracts its male euglossine bees with aromatic fatty acid derivatives such as a-pinene, limonene or trans-carvone oxide (TEICHERT et al, 2009). For a full account of the present knowledge of scents in Annonaceae flowers see Goodrich (2012).…”

Pollination systems involving floral mimicry of fruit: aspects of their ecology and evolution

“…Finally, several species of Annonaceae, Proteaceae and one cycad have been documented as having fruity and fermented floral (or cone) scents based on both human perception and chemical analyses, and are pollinated by beetles (Procheş & Johnson, ; Goodrich, ; Steenhuisen et al ., ). Jürgens et al .…”

“…For example, the tropical family Annonaceae has numerous species described as having ‘fruity’ floral scents. When described in more detail, the scents of individual species are frequently likened to specific and diverse fruit types including banana, pineapple, peach and apple (Goodrich, , and references therein). This would suggest that different species achieve ‘fruity’ odors through volatile blends which differ substantially in chemical composition.…”

“…Although many of these species are pollinated by beetles, these differences in scent chemistry may allow for more specialized attraction of various subsets of frugivorous beetles within the local community (Janzen, ). Furthermore, descriptions of Annonaceae floral scents often qualify the fruity odors as ‘ripe’, ‘overripe’, ‘fermented’ or ‘rancid’, indicating mimicry of specific temporal stages of fruit ripening and decay (Goodrich, ). Although descriptions of floral scent suggest that fruit mimicry might be common within the family, detailed analyses comparing floral cues to ecologically relevant potential models are lacking.…”