Floral morphology and reproductive biology in selected maple (Acer L.) species (Sapindaceae)

Abstract

This study focuses on variation in reproductive systems in Acer (maple) species, and how Acer might be a useful genus for understanding floral morphology and the evolution of these highly variable systems. The goals were (1) to conduct a survey of reproductive characters in the genus Acer with an emphasis on floral morphometrics of A. ginnala Maxim., A. tataricum L., and the hybrid A. ginnala 9 tataricum and (2) present a compilation of the reproductive biology of Acer based on the literature and online information. Morphometric analyses showed that the hybrid A. ginnala 9 tataricum exhibits intermediacy in vegetative morphology and some floral traits compared to the parents. Literature and an online survey revealed some information on the reproductive biology of 40 Acer species, plus the hybrid, representing only 32.3% of the taxonomic diversity. The reproductive modes of Acer include monoecy, dioecy, trioecy, andromonoecy, androdioecy, and andropolygamy, with a trend towards unisexuality. Temporal patterns of maturation of reproductive parts revealed duodichogamy, heterodichogamy, simultaneous, and dichogamy. The pollination syndrome is entomophilous, anemophilous, and ambophilous. We conclude that the evolutionary and geographic success of Acer lie in the versatility of sexual systems, diverse modes of maturation of reproductive organs, reproductive success, and the ability to colonise wider areas.

Population genetic variation characterization of the boreal tree Acer ginnala in Northern China

“…Moreover, being a perennial tree, long lived A. ginnala could have more opportunities to accumulate mutations or specialized microstructures in different populations. In addition, A. ginnala is an insect-pollinated species 39,40 with sexual propagation through seeds. This reproductive characteristic has significance for maintaining genetic diversity 36 .…”

Influence of local density and sex ratio on pollination in an ambophilous flowering plant

“…If ambophily indeed represents a functionally flexible pollination strategy, it raises questions as to why it is apparently relatively uncommon among angiosperms (see Culley et al., ). One explanation is that ambophily may occur more frequently than is reported, and indeed an increasing number of species have been described as ambophilous (Stelleman, ; Berry and Calvo, ; Vroege and Stelleman, ; Gomez and Zamora, ; Goodwillie, ; Totland and Sottocornola, ; Culley et al., ; Lázaro and Traveset, ; Gulías and Traveset, ; Yamasaki and Sakai, ; Rios et al., ; Wang et al., ; Rosado et al., ; Saunders, ). A second possibility is that ambophilous phenotypes may have reduced fitness compared to individuals adapted for a single pollination strategy.…”

Comparative analysis of pollen release biomechanics in Thalictrum: implications for evolutionary transitions between animal and wind pollination

“…An explicit prediction from this perspective is that wind pollination mechanisms were assembled from animal‐pollinated ancestors, piecemeal through a sequence of various intermediate stages rather than by a single deterministic and predictable pathway of trait change. The existence of intermediate stages is not especially controversial as increasing numbers of species are reported as ambophilous, with a mixture of wind and animal pollination (Stelleman, ; Berry & Calvo, ; Vroege & Stelleman, ; Gomez & Zamora, ; Goodwillie, ; Totland & Sottocornola, ; Culley et al ., ; Lázaro & Traveset, ; Gulías & Traveset, ; Yamasaki & Sakai, ; Ríos et al ., ; Wang et al ., ; Rosado et al ., ; Saunders, ), including several species of Thalictrum (Kaplan & Mulcahy, ; Davis, ; Steven & Waller, ; Timerman & Barrett, ).…”