How do visitation patterns vary among pollinators in relation to floral display and floral design in a generalist pollination system?

Dioecious plants constitute 7% of all angiosperm species, yet they occur in many habitat types, partially through the deployment of sexual dimorphisms that assist in reproduction. In the present work, the dioecious monocot Lomandra leucocephala ssp. robusta (Asparagaceae: Lomandroideae) was studied to understand how sexual dimorphisms can assist species conservation and inform us of a species’ potential significance in an ecosystem. Floral display was sexually dimorphic, as male inflorescences were displayed more prominently and more conspicuously in UV range. Male nectar analysed by thin-layer chromatography contained a higher glucose content than female nectar. However, both sexes contained hexose-rich nectar, a common indicator of generalist pollination, which was supported by observations of floral visitors. Floral extract comparison conducted via gas chromatography-mass spectrometry showed that male extracts contained more compounds that potentially convey greater resistance to biotic and abiotic threats. Chemical comparison of leaves by high performance liquid chromatography with peak area ratio analysis revealed this technique could be used as a tool for gender identification of individuals during non-flowering periods. Due to the generalist pollination mechanisms of L. leucocephala ssp. robusta, may have an important role in the conservation and support of local insect populations. The presence of chemical biotic and abiotic resistance may also make L. leucocephala ssp. robusta a significant contributor to the ongoing stabilisation of the sand dunes. Conservation efforts required for L. leucocephala ssp. robusta are likely to be minimal, as pollination services are provided by a diversity of pollinating taxa, including introduced species, which will be abundant regardless of variable flowering periods. Further observational study of L. leucocephala ssp. robusta pollinators and differences in pollinator visitation behaviours between sexes is recommended to better understand efficient pollination for the species, and potentially reveal a greater extent of ecosystem benefit for this species.

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Nocturnal ant integrates generalist pollination system in the Caatinga dry forest

Brazilian Journal of Biology ◽

10.1590/1519-6984.235508 ◽

2022 ◽

Vol 82 ◽

Author(s):

A. Domingos-Melo ◽

T. L. Nadia ◽

I. R. Leal ◽

I. C. Machado

Keyword(s):

Dry Forest ◽

Pollination System ◽

Generalist Pollination

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Floral traits and reproduction ofAvicennia schauerianaMoldenke (Acanthaceae): a generalist pollination system in the Lamiales

Plant Species Biology ◽

10.1111/j.1442-1984.2011.00361.x ◽

2012 ◽

Vol 28 (1) ◽

pp. 70-80 ◽

Cited By ~ 12

Author(s):

TARCILA DE LIMA NADIA ◽

NANUZA LUIZA DE MENEZES ◽

ISABEL CRISTINA MACHADO

Keyword(s):

Floral Traits ◽

Pollination System ◽

Generalist Pollination

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The generalist pollination system and reproductive success of Calluna vulgaris in the Upper Ardenne

Canadian Journal of Botany ◽

10.1139/cjb-76-11-1843 ◽

1998 ◽

Vol 76 (11) ◽

pp. 1843-1851 ◽

Cited By ~ 3

Author(s):

Grégory Mahy ◽

Jacques De Sloover ◽

Anne-Laure Jacquemart

Keyword(s):

Reproductive Success ◽

Calluna Vulgaris ◽

Pollination System ◽

Generalist Pollination

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A comparative study on the reproductive success of two rewarding Habenaria species (Orchidaceae) occurring in roadside verge habitats

BMC Plant Biology ◽

10.1186/s12870-021-02968-w ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Wenliu Zhang ◽

Jiangyun Gao

Keyword(s):

Reproductive Success ◽

Fruit Set ◽

Plant Density ◽

Flowering Plant ◽

Floral Display ◽

Pollinator Behaviour ◽

Factors Affecting ◽

Nectar Sugar ◽

Viable Seeds ◽

Viable Embryo

Abstract Background Most orchid species have been shown to be severely pollination limited, and the factors affecting reproductive success have been widely studied. However, the factors determining the reproductive success vary from species to species. Habenaria species typically produce nectar but exhibit variable fruit set and reproductive success among species. Here, we investigated the influence of the flowering plant density, inflorescence size, breeding system, and pollinator behaviour on the reproductive success of two rewarding Habenaria species. Results Our observations indicated that Habenaria limprichtii and H. petelotii co-occur in roadside verge habitats and present overlapping flowering periods. Both species were pollination limited, although H. limprichtii produced more fruits than H. petelotii under natural conditions during the 3-year investigation. H. petelotii individuals formed distinct patches along roadsides, while nearly all H. limprichtii individuals clustered together. The bigger floral display and higher nectar sugar concentration in H. limprichtii resulted in increased attraction and visits from pollinators. Three species of effective moths pollinated for H. limprichtii, while Thinopteryx delectans (Geometridae) was the exclusive pollinator of H. petelotii. The percentage of viable seeds was significantly lower for hand geitonogamy than for hand cross-pollination in both species. However, H. limprichtii may often be geitonogamously pollinated based on the behaviours of the pollinators and viable embryo assessment. Conclusions In anthropogenic interference habitats, the behaviours and abundance of pollinators influence the fruit set of the two studied species. The different pollinator assemblages in H. limprichtii can alleviate pollinator specificity and ensure reproductive success, whereas the more viable embryos of natural fruit seeds in H. petelotii suggested reducing geitonogamy by pollinators in the field. Our results indicate that a quantity-quality trade-off must occur between species with different breeding strategies so that they can fully exploit the existing given resources.

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Generalized olfactory detection of floral volatiles in the highly specialized Greya-Lithophragma nursery pollination system

Arthropod-Plant Interactions ◽

10.1007/s11829-021-09809-5 ◽

2021 ◽

Author(s):

Florian P. Schiestl ◽

Erika A. Wallin ◽

John J. Beck ◽

Magne Friberg ◽

John N. Thompson

Keyword(s):

Selective Advantage ◽

Floral Volatiles ◽

Pollination System ◽

Allopatric Populations ◽

Evolutionary Scenario ◽

Plant Recognition ◽

Hexahydrofarnesyl Acetone ◽

Electroantennographic Detection ◽

Local Host ◽

Olfactory Detection

AbstractVolatiles are of key importance for host-plant recognition in insects. In the pollination system of Lithophragma flowers and Greya moths, moths are highly specialized on Lithophragma, in which they oviposit and thereby pollinate the flowers. Floral volatiles in Lithophragma are highly variable between species and populations, and moths prefer to oviposit into Lithophragma flowers from populations of the local host species. Here we used gas chromatography coupled with electroantennographic detection (GC-EAD) to test whether Greya moths detect specific key volatiles or respond broadly to many volatiles of Lithophragma flowers. We also addressed whether olfactory detection in Greya moths varies across populations, consistent with a co-evolutionary scenario. We analyzed flower volatile samples from three different species and five populations of Lithophragma occurring across a 1400 km range in the Western USA, and their sympatric female Greya politella moths. We showed that Greya politella detect a broad range of Lithophragma volatiles, with a total of 23 compounds being EAD active. We chemically identified 15 of these, including the chiral 6, 10, 14-trimethylpentadecan-2-one (hexahydrofarnesyl acetone), which was not previously detected in Lithophragma. All investigated Lithophragma species produced the (6R, 10R)-enantiomer of this compound. We showed that Greya moths detected not only volatiles of their local Lithophragma plants, but also those from allopatric populations/species that they not encounter in local populations. In conclusion, the generalized detection of volatiles and a lack of co-divergence between volatiles and olfactory detection may be of selective advantage for moths in tracking hosts with rapidly evolving, chemically diverse floral volatiles.

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Evolution of floral morphology and pollination system in Bignonieae (Bignoniaceae)

American Journal of Botany ◽

10.3732/ajb.0900182 ◽

2010 ◽

Vol 97 (5) ◽

pp. 782-796 ◽

Cited By ~ 42

Author(s):

Suzana Alcantara ◽

Lúcia G. Lohmann

Keyword(s):

Floral Morphology ◽

Pollination System

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The role of ultraviolet reflectance and pattern in the pollination system of Hypoxis camerooniana (Hypoxidaceae)

AoB Plants ◽

10.1093/aobpla/plz057 ◽

2019 ◽

Vol 11 (5) ◽

Author(s):

Yannick Klomberg ◽

Raissa Dywou Kouede ◽

Michael Bartoš ◽

Jan E J Mertens ◽

Robert Tropek ◽

...

Keyword(s):

Plant Species ◽

Central Africa ◽

Complete Removal ◽

Reproductive Organs ◽

Specific Pattern ◽

Flowering Plant ◽

Pollination System ◽

Mount Cameroon ◽

Uv Reflectance ◽

Montane Grasslands

Abstract Apart from floral morphology and colours perceived by the human eye, ultraviolet (UV) reflectance acts as an important visual advertisement of numerous flowering plant species for pollinators. However, the effect of UV signalling on attracting pollinators of particular plant species is still insufficiently studied, especially in the Afrotropics. Therefore, we studied the pollination system of Hypoxis camerooniana in montane grasslands of Mount Cameroon, West/Central Africa. We focused mainly on the effects of the flowers’ UV reflectance on its visitors. We experimentally removed UV reflection from petals either completely or partially. Thereafter, flower visitors were recorded and pistils were collected post-flowering to quantify germinated pollen tubes per treatments. The most important visitors were bees, followed by flies. Due to their contacts with reproductive organs bees are considered as the primary pollinators. Visitation rates were lower when UV reflectance was completely removed, whereas the decrease of frequency on half-treated flowers did not differ significantly from control treatments. The complete removal of UV also affected bees’ landing behaviour, but not that of flies. We showed that the presence of UV reflectance is more important than UV pattern for bees visiting flowers of H. camerooniana. We hypothesize that exploiting all flowers irrespective of their pattern can be more efficient for pollinators in the open grasslands of high altitudes to spot these relatively scarce flowers by their UV reflectance. Furthermore, we highlight the necessity of both experimental and natural controls in similar studies to control for additional effects of the used UV manipulations. Many plants advertise their flowers with UV reflectance visible to their insect visitors. By manipulating the UV reflectance and pattern of Hypoxis camerooniana in the Afromontane grasslands of Mount Cameroon, we have shown how crucial it is for the predominant visitor, bees. Both bees' preferences for flowers and their behaviour during visits are influenced by changes in UV reflectance. However, the presence of some UV signal is more important than the specific pattern. Especially in montane grasslands with higher UV irradiation, the UV floral colours are important for recognition of flowers by potential pollinators.

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