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Do flower color and floral scent of silene species affect host preference of Hadena bicruris, a seed-eating pollinator, under field conditions?

Page P, Favre A, Schiestl FP, Karrenberg S - PLoS ONE (2014)

Bottom Line: Emission of these compounds did not differ significantly between the two Silene species.Our results suggest that flower color plays an important role in the specific interaction of H. bicruris with its preferred host S. latifolia.This would weaken the predictability of the plant's costs and benefits of the interaction and act to maintain an imperfect degree of specialization.

View Article: PubMed Central - PubMed

Affiliation: ETH Zurich, Institute of Integrative Biology (IBZ), Zurich, Switzerland.

ABSTRACT
Specialization in plant-insect interactions is an important driver of evolutionary divergence; yet, plant traits mediating such interactions are poorly understood. In this study, we investigated how flower color and floral scent are related to seed predation by a seed-eating pollinator. We used field-transplanted recombinant F2 hybrids between Silene latifolia and S. dioica that are the preferred and alternative hosts of the moth Hadena bicruris and crosses within these species for comparison. We scored seed predation and flower color and analyzed floral scent. Pinker S. dioica-like flowers and emission of α-pinene decreased the odds of seed predation while emission of benzyl acetate and 6-methyl-5-hepten-2-one increased the odds of seed predation. Emission of these compounds did not differ significantly between the two Silene species. Our results suggest that flower color plays an important role in the specific interaction of H. bicruris with its preferred host S. latifolia. The compounds α-pinene, benzyl acetate and 6-methyl-5-hepten-2-one could represent non-specific deterrents and attractants to ovipositing moths. Alternatively, emission of these compounds could be related to herbivory or pathogen attack and act as a signal for host quality. This would weaken the predictability of the plant's costs and benefits of the interaction and act to maintain an imperfect degree of specialization.

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Related in: MedlinePlus

Effect of flower color and floral scent compounds on seed predation.Effect size estimates with standard errors from a logistic regression model of primary seed predation by the moth Hadena bicruris on inter-specific F2 hybrids between the moth's preferred host Silene latifolia and its alternative host S. dioica. Measurements were log-transformed where appropriate and all explanatory variables were scaled and standardized before analysis (compare Table S6). Significant effects (P<0.05) are indicated with an asterisk.
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pone-0098755-g002: Effect of flower color and floral scent compounds on seed predation.Effect size estimates with standard errors from a logistic regression model of primary seed predation by the moth Hadena bicruris on inter-specific F2 hybrids between the moth's preferred host Silene latifolia and its alternative host S. dioica. Measurements were log-transformed where appropriate and all explanatory variables were scaled and standardized before analysis (compare Table S6). Significant effects (P<0.05) are indicated with an asterisk.

Mentions: The logistic regression model on primary seed predation by H. bicruris in the 91 F2 individuals thus contained flower color, 16 scent compounds, the block effect (four blocks, i.e. three variables) and the intercept, 20 explanatory variables in total. This is an acceptable ratio of experimental units to variables of 4.55 [56]. The model had a residual deviance of 78.32 on 68 degrees of freedom indicating that the data are not over-dispersed [52] and was significant in comparison to the model (X2 = 43.84, Pχ2 = 0.0037). In this model, flower color score and emission of α-pinene significantly decreased the odds of seed predation whereas emission of benzyl acetate and 6-methyl-5-hepten-2-one increased the odds of seed predation (Fig. 2, Table S6). Note that flower color and floral scent measurements were standardized before analysis (see Material and Methods section), thus effect estimates in log odds ratio units are given for increases of one standard deviation in the trait.


Do flower color and floral scent of silene species affect host preference of Hadena bicruris, a seed-eating pollinator, under field conditions?

Page P, Favre A, Schiestl FP, Karrenberg S - PLoS ONE (2014)

Effect of flower color and floral scent compounds on seed predation.Effect size estimates with standard errors from a logistic regression model of primary seed predation by the moth Hadena bicruris on inter-specific F2 hybrids between the moth's preferred host Silene latifolia and its alternative host S. dioica. Measurements were log-transformed where appropriate and all explanatory variables were scaled and standardized before analysis (compare Table S6). Significant effects (P<0.05) are indicated with an asterisk.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4048206&req=5

pone-0098755-g002: Effect of flower color and floral scent compounds on seed predation.Effect size estimates with standard errors from a logistic regression model of primary seed predation by the moth Hadena bicruris on inter-specific F2 hybrids between the moth's preferred host Silene latifolia and its alternative host S. dioica. Measurements were log-transformed where appropriate and all explanatory variables were scaled and standardized before analysis (compare Table S6). Significant effects (P<0.05) are indicated with an asterisk.
Mentions: The logistic regression model on primary seed predation by H. bicruris in the 91 F2 individuals thus contained flower color, 16 scent compounds, the block effect (four blocks, i.e. three variables) and the intercept, 20 explanatory variables in total. This is an acceptable ratio of experimental units to variables of 4.55 [56]. The model had a residual deviance of 78.32 on 68 degrees of freedom indicating that the data are not over-dispersed [52] and was significant in comparison to the model (X2 = 43.84, Pχ2 = 0.0037). In this model, flower color score and emission of α-pinene significantly decreased the odds of seed predation whereas emission of benzyl acetate and 6-methyl-5-hepten-2-one increased the odds of seed predation (Fig. 2, Table S6). Note that flower color and floral scent measurements were standardized before analysis (see Material and Methods section), thus effect estimates in log odds ratio units are given for increases of one standard deviation in the trait.

Bottom Line: Emission of these compounds did not differ significantly between the two Silene species.Our results suggest that flower color plays an important role in the specific interaction of H. bicruris with its preferred host S. latifolia.This would weaken the predictability of the plant's costs and benefits of the interaction and act to maintain an imperfect degree of specialization.

View Article: PubMed Central - PubMed

Affiliation: ETH Zurich, Institute of Integrative Biology (IBZ), Zurich, Switzerland.

ABSTRACT
Specialization in plant-insect interactions is an important driver of evolutionary divergence; yet, plant traits mediating such interactions are poorly understood. In this study, we investigated how flower color and floral scent are related to seed predation by a seed-eating pollinator. We used field-transplanted recombinant F2 hybrids between Silene latifolia and S. dioica that are the preferred and alternative hosts of the moth Hadena bicruris and crosses within these species for comparison. We scored seed predation and flower color and analyzed floral scent. Pinker S. dioica-like flowers and emission of α-pinene decreased the odds of seed predation while emission of benzyl acetate and 6-methyl-5-hepten-2-one increased the odds of seed predation. Emission of these compounds did not differ significantly between the two Silene species. Our results suggest that flower color plays an important role in the specific interaction of H. bicruris with its preferred host S. latifolia. The compounds α-pinene, benzyl acetate and 6-methyl-5-hepten-2-one could represent non-specific deterrents and attractants to ovipositing moths. Alternatively, emission of these compounds could be related to herbivory or pathogen attack and act as a signal for host quality. This would weaken the predictability of the plant's costs and benefits of the interaction and act to maintain an imperfect degree of specialization.

Show MeSH
Related in: MedlinePlus