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Abstract Identifying key traits that can serve as proxies for species drought resistance is crucial for predicting and mitigating the effects of climate change in diverse plant communities. Turgor loss point (π_tlp) is a recently emerged trait that has been linked to species distributions across gradients of water availability. However, a direct relationship between π_tlpand species ability to survive drought has yet to be established for woody species. Using a manipulative field experiment to quantify species drought resistance (i.e., their survival response to drought), combined with measurements of π_tlpfor 16 tree species, we show a negative relationship between π_tlpand seedling drought resistance. Using long‐term forest plot data, we also show that π_tlppredicts seedling survival responses to a severe El Niño‐related drought, although additional factors are clearly also important. Our study demonstrates that species with lower π_tlpexhibit higher survival under both experimental and natural drought. These results provide a missing cornerstone in the assessment of the traits underlying drought resistance in woody species and strengthen π_tlpas a proxy for evaluating which species will lose or win under projections of exacerbating drought regimes. 

Abstract As extreme climate events are predicted to become more frequent because of global climate change, understanding their impacts on natural systems is crucial. Tropical forests are vulnerable to droughts associated with extreme El Niño events. However, little is known about how tropical seedling communities respond to El Niño–related droughts, even though patterns of seedling survival shape future forest structure and diversity. Using long‐term data from eight tropical moist forests spanning a rainfall gradient in central Panama, we show that community‐wide seedling mortality increased by 11% during the extreme 2015–16 El Niño, with mortality increasing most in drought‐sensitive species and in wetter forests. These results indicate that severe El Niño–related droughts influence understory dynamics in tropical forests, with effects varying both within and across sites. Our findings suggest that predicted increases in the frequency of extreme El Niño events will alter tropical plant communities through their effects on early life stages.