DOI: 10.5061/dryad.573n5tbjg
title: Drivers of phenological transitions in the seedling life stage

description: Plant functional ecology research has primarily focused on juvenile and
 adult plants even though regeneration from seed can be the most
 consequential life-history bottleneck with cascading influence on later
 stages of growth and reproduction. Understanding relationships among
 phenology, morphology, and growth-related functional traits has improved
 our knowledge of plant life-history strategies and adaptive responses to
 changing climate. However, whether relationships among phenological and
 morpho-physiological traits exist during plant regeneration is unknown. We
 also lack understanding of the relative importance of these relationships
 compared with those of regeneration phenology with other factors like
 plant phylogeny, geographic location, and whether a species is native or
 non-native to the location.  To better understand these gaps in
 knowledge, we evaluated three phenological traits (days to germination,
 first and third true leaves) and six morpho-physiological traits (seed
 mass, relative growth rate, root elongation rate, root:shoot ratio,
 specific leaf area, seedling C:N) associated with regeneration for 131
 forb species from six globally distributed grasslands. 
 Morpho-physiological traits showed several significant correlations with
 phenological traits. Boosted regression trees revealed that their relative
 importance in predicting phenological traits varied among the three
 phenological stages (34-51%). Interestingly, the relative importance of
 morpho-physiological traits on the phenological stages was comparable to
 that of phylogeny (36-46%). In general, species with faster phenologies
 produced seedlings that grew faster. The influence of geographic location
 on phenological traits was strongest at germination (29%) and decreased
 (8-15%) at later phenological stages. Native vs non-native origin had
 little to no impact (0-2%) on regeneration phenology.  Strong
 relationships between days to germination and geographic location indicate
 signatures of local adaptation in the earliest life stages. Similar
 morpho-physiological trait values between native and non-native forbs
 imply that trait matching may be essential for non-native establishment.
 While associations between phenological and morpho-physiological traits
 during regeneration have not been previously recognized, our results
 suggest that these are complex and variable across plant regeneration.
 Better understanding of these associations and their variation across
 plant life stages may help capture species shifts with ongoing climate
 change and be used to develop novel approaches to seed-based restoration.
description: These are all measurements taken from growth chamber and
 greenhouse grown plants. The data are raw. 
description: # Drivers of phenological transitions in the seedling life stage
 [https://doi.org/10.5061/dryad.573n5tbjg](https://doi.org/10.5061/dryad.573n5tbjg) ## Description of the data and file structure We collected phenological and morpho-physiological trait data for 131 forb species from six grasslands. Plants were grown in growth chamber or greenhouse conditions, harvested, and measured at different phenological stages.  ### Files and variables #### File: Slate\_et\_al\_2024\_data.csv **Description:**  ##### Variables * Region: Species were evaluated from six study regions * Origin: Species were either native or exotic to the study region where their seed was collected * species: Species code * Genus: Genus name * Epitel: Epitel * Species.1: Full species name * source: Seeds were either field collected or purchased * Family: Family name * strategy_detail: Life history strategy (perennial or annual) * days_to_Germ: Days to Germination is the number of days between starting seeds and protrusion of a radicle (d) * days_to_TrueLf: Days to true leaf is the number of days from germination to true leaf (d) * day_third_leaves: Days to third leaf is the difference between the date of sowing and the date seedlings produced a third leaf (d) * seed_mass: Seed mass is the weight of an individual seed after drying for 48 hrs (mg) * Rel_gr_rate: Relative growth rate was calculated as whole seedling mass divided by the number of days between germination and first true leaf (mg/d) * RootElongRate: Root elongation rate is the difference in root length between germination and first true leaf divided by the number of days between germination and first true leaf (mm/d) * root_to_shootMass: Ratio of root to shoot biomass (no units) * CN: Seedling C:N biomass ratio (no units) * SLA: Specific leaf area (mm2/mg) ## Code/software No special code or software is needed to view these data.