Appendix E. A photo of a common garden site in the coastal prairie at Bodega Marine Reserve.

A photo of a common garden site in the coastal prairie at Bodega Marine Reserve

Appendix A. Methodological details of common garden experiments for testing effects of pathogens and herbivores on native and introduced clover species.

Methodological details of common garden experiments for testing effects of pathogens and herbivores on native and introduced clover species

Appendix C. Detailed description of fungicide experiments.

Detailed description of fungicide experiments

Appendix B. Isolation, identification, and geographical origin of fungi from clovers.

Isolation, identification, and geographical origin of fungi from clovers

Appendix D. Results of hypothesis testing:tables of F statistics, P values, and additional analyses described in the text.

Results of hypothesis testing:tables of F statistics, P values, and additional analyses described in the text

Weighted means of intercept (<i>b</i>_•0) and slope (<i>b</i>_•1) from the study-unit regressions described in S2 Table, for each of five types of interaction type and measured impact.

<p>^aCoefficients are for the model <i>RI</i> = <i>b</i>_•0 + <i>b</i>_•1log₁₀(<i>PD</i> + 1), where <i>PD</i> is the phylogenetic distance in Ma from the most strongly affected host.</p><p>^bStandard errors for the weighted means are not available for disease—enemy development category because there was only one study unit (N), but were significant in the original study.</p><p>^cThe 95% confidence intervals are presented for the weighted mean slopes.</p><p>Weighted means of intercept (<i>b</i>_•0) and slope (<i>b</i>_•1) from the study-unit regressions described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0123758#pone.0123758.s004" target="_blank">S2 Table</a>, for each of five types of interaction type and measured impact.</p

Appendix E. Logistic regression results for the effect of canopy fungi (presence/absence of fungi on nearest mature conspecific), juvenile density (number of juveniles in 3-m radius around adult), and percentage of canopy openness on the proportion of juvenile Cleistanthus myrianthus colonized by epifoliar fungi at Cape Tribulation, Australia.

Logistic regression results for the effect of canopy fungi (presence/absence of fungi on nearest mature conspecific), juvenile density (number of juveniles in 3-m radius around adult), and percentage of canopy openness on the proportion of juvenile Cleistanthus myrianthus colonized by epifoliar fungi at Cape Tribulation, Australia

The Impact of Plant Enemies Shows a Phylogenetic Signal

<div><p>The host ranges of plant pathogens and herbivores are phylogenetically constrained, so that closely related plant species are more likely to share pests and pathogens. Here we conducted a reanalysis of data from published experimental studies to test whether the severity of host-enemy interactions follows a similar phylogenetic signal. The impact of herbivores and pathogens on their host plants declined steadily with phylogenetic distance from the most severely affected focal hosts. The steepness of this phylogenetic signal was similar to that previously measured for binary-response host ranges. Enemy behavior and development showed similar, but weaker phylogenetic signal, with oviposition and growth rates declining with evolutionary distance from optimal hosts. Phylogenetic distance is an informative surrogate for estimating the likely impacts of a pest or pathogen on potential plant hosts, and may be particularly useful in early assessing risk from emergent plant pests, where critical decisions must be made with incomplete host records.</p></div

Appendix D. Logistic regression results for the effect of phylogenetic distance (My), joint relative abundance (JRA), or the interaction (MyxJRA) on the probability that two plant species shared epifoliar fungal symbionts, from radial transects at San Lorenzo, Panama, and Cape Tribulation, Australia.

Logistic regression results for the effect of phylogenetic distance (My), joint relative abundance (JRA), or the interaction (MyxJRA) on the probability that two plant species shared epifoliar fungal symbionts, from radial transects at San Lorenzo, Panama, and Cape Tribulation, Australia

Observed phylogenetic signal in severity of impact of plant-enemy interactions.

<p>Regressions are based on weighted mean regression coefficients of relative impact on the log of the phylogenetic distance between hosts in meta-analysis of published studies. Regression coefficients are given in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0123758#pone.0123758.t001" target="_blank">Table 1</a>. Thick lines are based on mean intercept and slope, and the thin lines are 95% confidence intervals. For comparison in panels A and B, the dashed black lines show the expected probability that two hosts at that phylogenetic distance would share a particular enemy based on re-analysis of data in Gilbert et al. [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0123758#pone.0123758.ref018" target="_blank">18</a>], using the present phylogenetic tree. In panel C, Pathogen development has no confidence intervals because it was derived from only one study unit (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0123758#pone.0123758.t001" target="_blank">Table 1</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0123758#pone.0123758.s001" target="_blank">S1 Fig</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0123758#pone.0123758.s003" target="_blank">S1 Table</a>).</p