Effects of ants on pollinator performance in a distylous pericarpial nectary-bearing Rubiaceae in Brazilian Cerrado

Sociobiology ◽  
2020 ◽  
Vol 67 (2) ◽  
pp. 173
Author(s):  
Bruno De Sousa-Lopes ◽  
Eduardo Soares Calixto ◽  
Eduardo Soares Calixto ◽  
Helena Maura Torezan-Silingardi ◽  
Helena Maura Torezan-Silingardi ◽  
...  
Keyword(s):  
Indirect Cost ◽  
Field Study ◽  
Brazilian Cerrado ◽  
Effective Protection ◽  
Cross Pollination ◽  
Floral Phenology ◽  
Floral Visitors ◽  
Pollinator Performance ◽  
Pollination Systems

Besides the eff ectiveness of floral visitors, to better understand pollination systems is necessary to consider the role of predators. Ants are ubiquitous on the vegetation, especially on plants bearing extrafloral (EFNs) and pericarpial nectaries (PNs). Both EFNs and PNs reward ants which in turn provide to plants effective protection against herbivores. However, ants can also repel pollinators and cause an indirect cost for the plant partner, although the role of ants on pollinators’ performance has rarely been assessed in Neotropics, mainly on PN-bearing plants. Here, our main aim was, through an experimental field study in terms of ant’s presence versus absence, to test the hypothesis that ants dissuade floral visitors by decreasing the time spent during visits on the PN-bearing Declieuxia fruticosa. Additionally, we recorded floral phenology, and quantified and qualified floral visits. We showed that bees were the most frequent pollinators and the presence of ants dissuades them. In ant presence, pollinators were on average 30% faster than without ants. Since D. fruticosa produces fruits mainly after cross-pollination, the role of ants may be profi table to plants as they induce pollinators to do shorter visits and search for other fl owers in conspecifi c plants. Therefore, pollinators avoid stay at longer on plants with ants in order to avoid attacks, which may contribute to plant outcrossing. However, whether positive or negative the effects of ants on D. fruticosa reproduction are, they remain to be studied.

Visual and olfactory floral cues related to ambophilous pollination systems in Poaceae

2019 ◽  
Author(s):  
Isadora Schulze-Albuquerque ◽  
Ana Carolina Galindo Da Costa ◽  
Paulo Milet-Pinheiro ◽  
Daniela Maria Do Amaral Ferraz Navarro ◽  
William Wayt Thomas ◽  
...  
Keyword(s):  
Grass Species ◽  
Wind Pollination ◽  
Pollen Vectors ◽  
Pollinating Insects ◽  
Floral Visitors ◽  
Pollen Vector ◽  
Pollination Systems ◽  
Chloris Barbata ◽  
Floral Cues

Abstract Usually considered anemophilous, grasses (Poaceae) have been the subject of few studies that recorded insects visiting their flowers. Such visitors, with wind, could act as pollen vectors in a possible ambophilous system. Since colour and scent are floral cues attracting pollinating insects, we aimed to provide the first insights into how these cues could be involved in the attraction of pollinators by grasses. Chloris barbata, Paspalum maritimum (with two morphotypes), P. millegrana and Urochloa plantaginea were studied. We determined the role of each pollen vector (wind and insect) and we registered the frequency of floral visitors. Also, we characterized the colour reflectance of glumes, anthers and stigmas and we determined the colour space in the bee colour hexagon and the chemical composition of floral scents. The floral structures of each species reflect colour differently and are perceived differently by pollinators. Furthermore, the volatile organic compounds detected are similar to those found in entomophilous species. In two of the grass species, we registered eight species of visitors, including bees, wasps and flies. Overall, wind was the most important vector for reproductive success. Insects, however, may induce wind pollination by creating pollen clouds when they visit inflorescences.

A field study of Value-Based Management sophistication: The role of shareholders

2015 ◽  
pp. 65-100
Author(s):  
Andrea Dello Sbarba ◽  
Riccardo Giannetti ◽  
Alessandro Marelli
Keyword(s):  
Field Study ◽  
Value Based Management

“Wi, se kretyènn mwen ye” (Yes I am Christian)

2011 ◽  
Vol 5 (2) ◽  
pp. 180-192 ◽  
Author(s):  
Nadège Mézié
Keyword(s):  
Field Study ◽  
Religious Identity ◽  
Research Strategy ◽  
Beliefs And Practices ◽  
Christian Woman

During a field study of a year and a half in the Haitian mountains, I was forced to re-evaluate my research strategy, and consequently the object of my study, after a setback that denied me access to the American evangelical mission, which I had hoped to study from within. This failure to integrate as a non-Protestant researcher, led me to adopt a methodological falsehood to allow me to penetrate the Haitian evangelical mission. The researcher who chooses methodological falsehood has to fashion a passing and superficial redefinition of her appearance, beliefs and practices, and live her new religious identity according to the prevalent beliefs and norms. This paper will focus on the fieldworker’s daily performance in her role of “Christian woman,” and the strategies put in place to respond to the prescriptive criteria of the role being played.

Phase field study of acicular growth: Role of elasticity in Widmanstätten structure

2014 ◽  
Vol 72 ◽  
pp. 200-210 ◽  
Author(s):  
Maeva Cottura ◽  
Benoît Appolaire ◽  
Alphonse Finel ◽  
Yann Le Bouar
Keyword(s):  
Field Study ◽  
Phase Field

To share or not to share? A moderated mediation model of the relationship between perceived overqualification and knowledge sharing

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Lijing Zhao ◽  
Shuming Zhao ◽  
Hao Zeng ◽  
Jingyi Bai
Keyword(s):  
Knowledge Sharing ◽  
Field Study ◽  
Identity Theory ◽  
Moderated Mediation ◽  
Experiment Study ◽  
Content Type ◽  
Mediating Role ◽  
Perceived Overqualification ◽  
Moderating Role

PurposeDrawing on identity theory and the symbolic interactionism perspective of identity theory, this study aims to construct a moderated mediation framework to test the effects of perceived overqualification (POQ) on knowledge sharing (KS) through professional identity threat (PIT) and the moderating role of coworkers' help-seeking behavior (CHSB).Design/methodology/approachThis paper uses a quantitative multistudy research design with a combination of a scenario experiment (Study 1) and a two-wave field study among 220 supervisor-subordinate dyads at a power company in China. Using analysis of variance, confirmatory factor analysis (CFA) and bootstrapping method, the authors validated the research hypothesis.FindingsIn the scenario experiment study (study 1), the authors find that POQ is positively related to PIT and that CHSB negatively moderates the positive impact of POQ on PIT. The field study (study 2) replicated the above findings and found that PIT mediates the negative effect of POQ on KS. In addition, CHSB negatively moderates the mediating role of PIT between POQ and KS.Originality/valueFirst, the current study extended the nomological network of POQ research by examining its influence on employees' KS. Second, this study empirically investigated the mediating role of PIT, which provided a new explanatory mechanism for the influence of POQ. Finally, this study demonstrates the moderating role of CHSB—a situational factor that has been ignored in previous studies.

Sign in / Sign up

Export Citation Format

Share Document