DOI: 10.5061/dryad.hqbzkh1tt
title: Data from: Evolution of drought resistance strategies following the introduction of white clover (Trifolium repens L.)

description: Background and Aims: Success during colonization likely depends on growing
 quickly and tolerating novel and stressful environmental conditions.
 However, rapid growth, stress avoidance, and stress tolerance are
 generally considered divergent physiological strategies.  
 Methods: We evaluate how white clover (Trifolium repens) has evolved to a
 divergent water regime following introduction to North America. We conduct
 RNAseq within a dry-down experiment utilizing accessions from low and high
 latitude populations from native and introduced ranges, and assess
 variation in dehydration avoidance (ability to avoid wilting) and
 dehydration tolerance (ability to survive wilting).   Key
 Results: Introduced populations are better at avoiding dehydration, but
 poorer at tolerating dehydration than native populations. There is a
 strong negative correlation between avoidance and tolerance traits and
 expression of most drought-associated genes exhibits similar tradeoffs.
 Candidate genes with expression strongly associated with dehydration
 avoidance are linked to stress signaling, closing stomata, and producing
 osmoprotectants. However, genes with expression linked to dehydration
 tolerance are associated with avoiding excessive ROS production and toxic
 bioproducts of stress responses. Several candidate genes show differential
 expression patterns between native and introduced ranges, and could
 underlie differences in drought resistance syndromes between ranges.
   Conclusions: These results suggest there has been strong
 selection following introduction for dehydration avoidance at the cost of
 surviving dehydration. More broadly, tradeoffs between dehydration
 avoidance and tolerance responses likely exist both at the genetic and
 phenotypic scales that will influence evolutionary responses and
 potentially limit the global spectrum of plant form and function.
description: # Data from: Evolution of drought resistance strategies following the
 introduction of white clover (Trifolium repens L.) Phenotype Dataset This
 dataset contains a single .csv file (fileA.csv) that contains data on
 drought resistance phenotypes and metadata for 27 individuals within the
 reported dry-down experiment. The dry-down experiment was conducted on ~2
 month old plants with the primary phenotypes of interest being the
 volumetric water content of soil at plant wilt and the survival following
 wilting. After wilting, plants were left for 48h before rehydration and
 survival was assessed after 72h. Further experimental details are provided
 in the parent paper: Hendrickson et al. 2025 (doi:10.1093/aob/mcaf037) ##
 Description of the data and file structure Each row of this .csv file
 represents an individual plant except for the first row header. There are
 no missing values. Descriptions of data within columns (Column -- Header
 Name -- Description): Column A -- PotN -- A tag used to identify each pot
 Column B -- Population -- the source population of the individual Column C
 -- City -- Nearest City to the source population Column D -- Latitude --
 Whether the individual was from a low or high latitude population Column E
 -- Location -- Whether the individual was from the native European
 range(EU) or introduced North American (NA) range Column F -- Flat -- The
 initial flat of the pot, i.e., location within the growth chamber Column G
 -- LeafND1 -- Leaves at the beginning of the experiment Column H --
 WiltedD -- Number of days from the beginning of the experiment to wilting
 Column I -- WiltedSM -- Volumetric water content (cm3/cm3) of the soil at
 time of wilting Column J -- Rehydration -- Survival after wilting, 0/1
 corresponds to died/survived respectively. Column K -- LatitudeDecimal --
 latitude in decimal degrees for the individual's source population
 Column L -- LongitudeDecimal -- longitude in decimal degrees for the
 individual's source population Column M -- annualea -- Annual
 Potential Evapotranspiration (mm/year) from CGIAR for the
 individual's source population Column N -- annualai -- Annual Aridity
 Index (Index x 10,000) from CGIAR for the individual's source
 population Please note that WorldClim data for populations cannot be
 posted to the Dryad repository, but is available for each population in
 Supplementary Table 1. ## Sharing/Access information RNAseq data for these
 samples can be accessed on NCBI's Sequence Read Archive (SRA) at
 Bioproject PRJNA1098360