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Abstract Background and aimsPlant interactions with soil microbial communities are critical for understanding plant health, improving horticultural and agricultural outcomes, and maintaining diverse natural communities. In some cases, disease suppressive soils enhance plant survival in the presence of pathogens. However, species-specific differences and seasonal variation complicate our understanding of the drivers of soil fungal communities and their consequences for plants. Here, we aim to describe soil fungal communities acrossRhododendronspecies and seasons as well as the test for fungal indicators ofRhododendronspecies in the soil. Further, we test possible mechanisms governing disease suppressive soils to the oomycete pathogenPhytophthora cinnamomi. Variation in disease susceptibility to this pathogen across species and clades allows us to test for possible fungal drivers of disease suppressive soils. MethodsWe conducted high throughput sequencing of the fungal communities found in soil collected under 14Rhododendronspecies and across 2 seasons (April, October) at two sites in Ohio, USA. Phylogenetic analyses were used to ask whether fungal community composition correlated with increased plant survival with the addition of whole soil communities from a prior greenhouse experiment. ResultsEffects ofRhododendronspecies (R² = 0.13), season (R² = 0.01) and their interaction on fungal communities (R² = 0.11) were statistically significant. Fungal community composition negatively correlated with survival following exposure to whole soil microbial communities, though this result depended on the presence ofR. minus. Forty-fiveTrichodermataxa were identified across our soil samples, and someTrichodermawere significantly associated with particularRhododendronspecies (e.g.Trichoderma atroviridewas associated withR. molle) in indicator species analyses. ConclusionThe correlation between plant responses to soil biotic communities and fungal community composition, as well as the presence of potential beneficial taxa such asTrichodermaand mycorrhizal fungi, are consistent with fungal-mediated survival benefits from the pathogenPhytophthora cinnamomi. 

Abstract There is an urgent need to synthesize the state of our knowledge on plant responses to climate. The availability of open-access data provide opportunities to examine quantitative generalizations regarding which biomes and species are most responsive to climate drivers. Here, we synthesize time series of structured population models from 162 populations of 62 plants, mostly herbaceous species from temperate biomes, to link plant population growth rates (λ) to precipitation and temperature drivers. We expect: (1) more pronounced demographic responses to precipitation than temperature, especially in arid biomes; and (2) a higher climate sensitivity in short-lived rather than long-lived species. We find that precipitation anomalies have a nearly three-fold larger effect onλthan temperature. Species with shorter generation time have much stronger absolute responses to climate anomalies. We conclude that key species-level traits can predict plant population responses to climate, and discuss the relevance of this generalization for conservation planning.