scholarly journals Evaluation of pollinator effectiveness based on pollen deposition and seed production in a gynodieocious alpine plant, Cyananthus delavayi

2017 ◽  
Vol 7 (20) ◽  
pp. 8156-8160 ◽  
Author(s):  
Hao Wang ◽  
Guo-Xing Cao ◽  
Lin-Lin Wang ◽  
Yong-Ping Yang ◽  
Zhi-Qiang Zhang ◽  
...  
Keyword(s):  
Seed Production ◽  
Pollen Deposition ◽  
Alpine Plant ◽  
Pollinator Effectiveness

scholarly journals Pollinator importance networks illustrate the crucial value of bees in a highly speciose plant community

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Gavin Ballantyne ◽  
Katherine C. R. Baldock ◽  
Luke Rendell ◽  
P. G. Willmer
Keyword(s):  
Plant Species ◽  
Community Level ◽  
Taxonomic Resolution ◽  
Pollen Deposition ◽  
Pollinator Effectiveness ◽  
Flower Visitors ◽  
Pollinator Importance ◽  
Visitation Frequency ◽  
Pollinator Performance ◽  
Number Of Plant Species

AbstractAccurate predictions of pollination service delivery require a comprehensive understanding of the interactions between plants and flower visitors. To improve measurements of pollinator performance underlying such predictions, we surveyed visitation frequency, pollinator effectiveness (pollen deposition ability) and pollinator importance (the product of visitation frequency and effectiveness) of flower visitors in a diverse Mediterranean flower meadow. With these data we constructed the largest pollinator importance network to date and compared it with the corresponding visitation network to estimate the specialisation of the community with greater precision. Visitation frequencies at the community level were positively correlated with the amount of pollen deposited during individual visits, though rarely correlated at lower taxonomic resolution. Bees had the highest levels of pollinator effectiveness, with Apis, Andrena, Lasioglossum and Osmiini bees being the most effective visitors to a number of plant species. Bomblyiid flies were the most effective non-bee flower visitors. Predictions of community specialisation (H2′) were higher in the pollinator importance network than the visitation network, mirroring previous studies. Our results increase confidence in existing measures of pollinator redundancy at the community level using visitation data, while also providing detailed information on interaction quality at the plant species level.

scholarly journals Autonomous pollination alleviates pollen limitation in the endemic Cienfuegosia yucatanensis Millsp. (Malvaceae)

2020 ◽  
Vol 99 (1) ◽  
pp. 80-91
Author(s):  
Víctor Parra-Tabla ◽  
Conchita Alonso
Keyword(s):  
Seed Production ◽  
Inbreeding Depression ◽  
Seed Weight ◽  
Pollen Limitation ◽  
Pollen Tubes ◽  
Pollen Deposition ◽  
Cross Pollination ◽  
The North ◽  
Hand Pollination ◽  
Self Compatibility

Background: Self-compatibility is common on endemic plant species, but pollen limitation and self-pollination could be risk factors. Study species: The endemic Cienfuegosia yucatanensis (Malvaceae), whose distribution is mainly restricted to the north coast of the peninsula of Yucatán, México. Questions: a) Are flowers of C. yucatanensis autonomous for pollination? b) Are C. yucatanensis fruit or seed-set limited by pollen deposition? and, c) Is there evidence of early inbreeding depression in C. yucatanensis? Study sites and dates: Two sites in the north of the peninsula of Yucatán in a seasonally dry scrubland, in the rainy season of 2013 and 2014. Methods: Number of flowers and fruits were weekly recorded. Flowers were collected to count the number of conspecific pollen load and the number of pollen tubes. Autonomous pollination and pollen limitation were evaluated with a hand-pollination experiment. Inbreeding depression on fruit and seed production, and seed weight was evaluated. Results: Flower and fruit production occur simultaneously and last from August to October. Conspecific pollen deposition on stigmas occurred through the whole flowering season and a maximum of pollen tubes was observed in August. Autonomous pollination treatment lead to similar fruit and seed production than cross-pollination, but open pollination produced significantly more seeds. No significant differences among self- and cross-pollination treatments on fruit and seed production or seed weight, were found.  Conclusions: Our results suggest that self-compatibility combined with a relatively efficient autonomous pollination, are suitable mechanisms for the reproductive assurance in C. yucatanensis, with no apparent effects of early inbreeding depression.

Pollen load, capsule weight, and seed production in three orchid species

1994 ◽  
Vol 72 (2) ◽  
pp. 249-255 ◽  
Author(s):  
H. C. Proctor ◽  
L. D. Harder
Keyword(s):  
Reproductive Success ◽  
Seed Production ◽  
Pollen Deposition ◽  
Pollen Load ◽  
Seed Number ◽  
Orchid Species ◽  
Liquid Suspension ◽  
Ovule Number ◽  
Cypripedium Calceolus ◽  
The Relationship

Relationships between pollen load, seed production, and capsule weight in orchids are important both theoretically and pragmatically. It has been hypothesized that pollen packets (pollinia) evolved in orchids because of selection to produce packages capable of fertilizing all ovules in an ovary; testing this hypothesis requires information about the relationship between pollen load and seed production. As well, because capsules contain thousands to millions of seeds, an easily measured correlate of seed number, such as capsule weight, would be valuable for studies of reproductive success. We hand-pollinated Cypripedium calceolus, Amerorchis rotundifolia, and Calypso bulbosa with different pollen loads, weighed capsules, and estimated seed number by subsampling from liquid suspension. Pollen load affected seed number in Calypso but had no significant effect in Cypripedium or Amerorchis. Capsule weight was positively associated with seed number in all species, but there was considerable variation in R2 across species (from 0.40 to 0.85), indicating that it is unwise to assume that capsule weight is a good measure of relative reproductive success. As well, our data suggest that size of the typical unit of pollen deposition rather than that of the entire pollinarium evolved to match ovule number in orchids. Key words: Orchidaceae, pollen load, capsule weight, seed set.

scholarly journals Can insect body pollen counts be used to estimate pollen deposition on pak choi stigmas

2011 ◽  
Vol 64 ◽  
pp. 25-31 ◽  
Author(s):  
B.G. Howlett ◽  
M.K. Walker ◽  
R. Rader ◽  
R.C. Butler ◽  
L.E. Newstrom-Lloyd ◽  
...  
Keyword(s):  
Strong Correlation ◽  
Pollen Grains ◽  
Insect Species ◽  
Pollen Deposition ◽  
Published Data ◽  
Data Recording ◽  
Pollinator Effectiveness ◽  
Pak Choi ◽  
Pollen Counts

Measuring pollen deposition onto stigmas by insects is one technique used to assess pollinator effectiveness but it can be unpredictable and timeconsuming as insects must visit test flowers This study examined whether a measurement of pollen grains from flowervisiting insects could be used to predict pollen deposited on stigmas Individuals were collected from four bee and six fly species as they visited pak choi flowers in commercial and trial seed fields to assess their body pollen Pollen was removed from insects by pressing their bodies (excluding activelycollected pollen on bees hind legs) with a cube of gelatinefuchsin In this study there appears to be a strong correlation between mean estimated pollen counts for each insect species and previously published data recording mean number of pollen grains deposited on stigmas for the same species Therefore the measurement of pollen grains directly from flowervisiting insects shows potential as a quicker and easier technique to assess pollinator effectiveness as insects can be directly collected from flowers

scholarly journals Contrasting pollination efficiency and effectiveness among flower visitors of Malva sylvestris, Borago officinalis and Onobrychis viciifolia

2017 ◽  
Vol 21 ◽  
Author(s):  
Anna Gorenflo ◽  
Tim Diekötter ◽  
Mark Van Kleunen ◽  
Volkmar Wolters ◽  
Frank Jauker
Keyword(s):  
Plant Species ◽  
Pollen Deposition ◽  
Pollinator Effectiveness ◽  
Borago Officinalis ◽  
Flower Visitor ◽  
Flower Visitors ◽  
Onobrychis Viciifolia ◽  
Single Visit ◽  
Malva Sylvestris ◽  
Visitation Frequency

Biotic pollination is an important factor for ecosystem functioning and provides a substantial ecosystem service to human food security. Not all flower visitors are pollinators, however, and pollinators differ in their pollination performances. In this study, we determined the efficiencies of flower visitors to the plant species Malva sylvestris, Borago officinalis and Onobrychis viciifolia by analysing stigmatic pollen deposition. We further calculated pollinator effectiveness by scaling up single-visit pollen deposition using visitation frequency. Flower-visitor groups differed in their efficiencies at the single-visit level and not all of them deposited more pollen compared to unvisited stigmas. Bumblebees tended to be most efficient in depositing pollen per single visit across the three plant species. Due to the by far highest visitation frequencies, Apis mellifera showed the highest effectiveness in depositing pollen per hour for M. sylvestris and B. officinalis, but not for O. viciifolia, for which the Bombus lapidarius complex was both the most frequent and the most effective pollinator group. Hence, the most frequent flower visitors were most effective in our study. For non-dominant pollinator groups, however, visitation frequencies contributed disproportionally to pollinator effectiveness. Thus, combining pollen deposition per single-visit with visitation frequency is necessary to reveal true pollinator performance and to better understand flower-visitor interactions. 

scholarly journals Hairiness: the missing link between pollinators and pollination

2016 ◽  
Author(s):  
Jamie R Stavert ◽  
Gustavo Liñán-Cembrano ◽  
Jacqueline R Beggs ◽  
Brad G Howlett ◽  
David E Pattemore ◽  
...  
Keyword(s):  
Functional Traits ◽  
Ecosystem Function ◽  
Ecosystem Functions ◽  
Body Region ◽  
Pollen Deposition ◽  
Ecological Communities ◽  
Pollen Load ◽  
Pollinator Effectiveness ◽  
Body Regions ◽  
The Face

Functional traits are the primary biotic component driving organism influence on ecosystem functions; in consequence, traits are widely used in ecological research. However, most animal trait-based studies use easy-to-measure characteristics of species that are at best only weakly associated with functions. Animal-mediated pollination is a key ecosystem function and is likely to be influenced by pollinator traits, but to date no one has identified functional traits that are simple to measure and have good predictive power. Here, we show that a simple, easy to measure trait (hairiness) can predict pollinator effectiveness with high accuracy. We used a novel image analysis method to calculate entropy values for insect body surfaces as a measure of hairiness. We evaluated the power of our method for predicting pollinator effectiveness by regressing pollinator hairiness (entropy) against single visit pollen deposition (SVD) and pollen loads on insects. We used linear models and AICC model selection to determine which body regions were the best predictors of SVD and pollen load. We found that hairiness can be used as a robust proxy of SVD. The best models for predicting SVD for the flower species Brassica rapa and Actinidia deliciosa were hairiness on the face and thorax as predictors (R2 = 0.98 and 0.91 respectively). The best model for predicting pollen load for B. rapa was hairiness on the face (R2 = 0.81). Accordingly, we suggest that the match between pollinator body region hairiness and plant reproductive structure morphology is a powerful predictor of pollinator effectiveness. We show that pollinator hairiness is strongly linked to pollination – an important ecosystem function, and provide a rigorous and time-efficient method for measuring hairiness. Identifying and accurately measuring key traits that drive ecosystem processes is critical as global change increasingly alters ecological communities, and subsequently, ecosystem functions worldwide.

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