[EN] Defining a phenotype is sometimes problematic in the case of modularly-built, nonunitary organisms with indeterminate growth dependent on environmental conditions, such as plants. This paper presents a proof of concept of the evolutionary significance of considering lifetime trajectories of individual plants as a component of their phenotypes. Plant size and inflorescence production were monitored for the whole reproductive lifespans of N = 128 individuals of the Mediterranean woody shrub Lavandula latifolia (Lamiaceae) over a 38-year period to address the following questions: Did individuals vary in lifetime trajectories of size and fecundity? and were parameters describing individual trajectories significant predictors of cumulative lifetime reproduction? Individuals differed widely in lifetime fecundity and in every parameter describing lifetime fecundity schedule (age at first and last reproduction, longevity, and mean, variance, skewness and kurtosis of lifetime temporal distribution of inflorescence production). Phenotypic selection analysis revealed significant relationships between parameters of individual lifetime schedules and a surrogate of relative fitness of individuals (cumulative lifetime production of inflorescences divided by the average for all individuals). Significant selection gradients involved positive and negative directional selection, as well as instances of nonlinear selection, which showed that plants with certain shapes of lifetime fecundity schedules had fitness advantage over others. The notion of plant phenotypes as trajectories was strongly supported by the combined findings that individuals differed greatly in their "appearances" regarding the way in which size and fecundity unfolded over lifetime, and that selection efficaciously "saw" such variation., [ES] La definición de un fenotipo resulta a veces problemática para organismos no unitarios de estructura modular y crecimiento indeterminado, como son las plantas. Este artículo presenta una prueba de concepto de la importancia evolutiva de considerar las trayectorias de vida de plantas individuales como un elemento de sus fenotipos. Durante un período de 38 años se registró el tamaño de la planta y la producción de inflorescencias durante toda la vida reproductiva de N = 128 individuos del arbusto leñoso mediterráneo Lavandula latifolia (Lamiaceae) para abordar las siguientes preguntas: ¿Existieron diferencias entre individuos en sus trayectorias vitales de tamaño y fecundidad?, ¿Los parámetros que describen las trayectorias individuales estuvieron relacionados con la reproducción acumulada durante la vida? Los individuos difirieron ampliamente en fecundidad acumulada a lo largo de la vida y en cada uno de los parámetros empleados para describir el cronograma de fecundidad a lo largo de la vida (edad en la primera y última reproducción, longevidad, y la media, varianza, asimetría y curtosis de la distribución temporal de la producción de inflorescencias a lo largo de la vida). El análisis de selección fenotípica reveló relaciones significativas entre los parámetros que describen los programas de vida individuales y la estima empleada para describir la aptitud relativa de los individuos (producción acumulada de inflorescencias durante toda la vida dividida por el promedio de todos los individuos). Los gradientes de selección obtenidos demostraron la existencia de selección direccional positiva y negativa, así como casos de selección no lineal sobre algunas variables. Ello vino a demostrar que plantas cuyas curvas de fecundidad durante la vida poseen ciertas formas tenían una ventaja de aptitud sobre las otras. Estos resultados apoyan la idea de que la forma de las trayectorias vitales de las plantas individuales conforma parte de sus fenotipos., While writing this article I benefitted from grants from Ministerio de Ciencia, Innovación y Universidades (PID2022-141530NB-C22, DISTEPIC) and Generalitat de Valencia (PROMETEO-2021/040, FocScales)., Peer reviewed

A study was undertaken between 1986-2023 were plant size and inflorescence production were monitored for the whole reproductive lifespans of N = 128 individuals of the Mediterranean woody shrub Lavandula latifolia (Lamiaceae) to address the following questions: Did individuals vary in lifetime trajectories of size and fecundity?, and Were parameters describing individual trajectories significant predictors of cumulative lifetime reproduction? The study site was in a mixed woodland of Pinus nigra and Quercus rotundifolia in the Sierra de Cazorla, Jaén province, southeastern Spain (site coordinates 37.9612ºN, 2.8847ºW). All plants were checked every summer (August-September) between 1987-2023. On each occasion, individuals found dead were digged up, collected, and their age at the time of death determined by ring counting. For each individual that remained alive, the number of inflorescences produced in the current year was counted and, on the even years, their size was assessed by measuring the two major axes of the canopy and then computing the area of the horizontal projection by assimilating the shape to an ellipse. The birth year of every monitored individual was determined by substracting the age at death from the year of death, and this information was then used to retrospectively compute the age of every plant in each study year. These data were then merged with those on yearly plant fecundity (number of inflorescences) and plant size measurements (estimated canopy area) to obtain individual lifetime profiles of size and fecundity in relation to current age., PID2022-141530NB-C22, DISTEPIC; PROMETEO-2021/040, FocScales, Peer reviewed

There is mounting evidence that plant responses to environmental stress are mediated by epigenetic factors, including DNA methylation. Understanding relationships between DNA methylation, plant development and individual fitness in contrasting environments is key to uncover potential impacts of epigenetic regulation on plant adaptation. Here, we used an experimental approach combining controlled alteration of epigenetic features with exposure to stress.
Two provenances of Erodium cicutarium were exposed to a demethylating agent (5-azacytidine) and recurrent drought, and effects on above- and belowground phenotypic traits related to early development, phenology and fitness assessed.
Application of 5-azacytidine significantly reduced DNA methylation in leaf and root tissues. This slowed plant development, delayed flowering, and reduced the number of inflorescences produced, independent of water regime. Recurrent drought reduced final above- and belowground biomass and inflorescence production, regardless of the 5-azacytidine exposure. Increased fruit and seed-set were the only adaptations to drought in E. cicutarium, together with an increased number of flowers per inflorescence in water-stressed plants previously treated with 5-azacytidine.
Epigenetic effects can desynchronize plant growth, flowering and senescence in both favourable and adverse environments. Future studies should focus on understanding intraspecific variation in ability to change the plant methylome in response to stress, and transgenerational transmission of such responses., Financial support was provided by grants EPIECOL-CGL2013-43352-P, EPIENDEM-CGL2016-76605-P, EPINTER-PID2019-104365GB-I00 and DISTEPIC-PID2022-141530NB-C22 (Ministerio de Ciencia e Innovación, Spanish Government). We acknowledge support for the publication fee from the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI)., Peer reviewed

[Data availability] The E. cicutarium genomic data are publicly available at the NCBI genome repository under genome project accession JBDFRG000000000, with the raw reads hosted at the NCBI Sequence Read Archive (SRA) repository under accession number SRR28842229. Protein sequences used in the phylogenetic analysis are available at Supplementary Methods 2 in this journal. RNA-seq raw reads are available at the NCBI SRA repository under accession numbers SRR29751957-SRR29751979. Scripts to analyze the data are publicly available at GitHub (https://github.com/rmblazquez/erodium-cicutarium-Transcriptomics-ebd). All Supplementary Figures 1 to 6, Supplementary Methods 1 to 3, Supplementary Results 1 and Supplementary Tables 1 to 12 are available at https://doi.org/10.25387/g3.30621302., Epigenetic regulation, and particularly modifications in DNA methylation, plays critical roles in plant adaptation. DNA methylation inhibitors have been used to investigate the relationship between DNA methylation and plastic plant phenotypes. However, their effect in gene expression regulation throughout the lifetime remains understudied in nonmodel plants. Here, we analyze the effects of seed exposure to the hypomethylating agent 5-azacytidine (5-azaC) in plant transcriptome. Seeds of Erodium cicutarium were soaked in either a solution of 5-azaC in DMSO or water with DMSO (control, hereafter) before sowing. Subsequently, RNA was extracted from juvenile roots, juvenile leaves, and adult leaves, and their transcriptomes were sequenced. Differential gene expression analysis was performed between control and treated samples for all tissues together and separately, presuming that changes between treatments will be substantially weaker than among tissues and developmental stages. Beforehand, a draft genome of E. cicutarium was assembled as reference for the transcriptome analysis. We found that 5-azaC upregulated chromomethylase CMT1 across all treated samples, and domain rearranged DNA methyltransferase DRM2 in juvenile roots. Furthermore, adult leaves showed more differentially expressed genes between control and 5-azaC-treated samples compared to juvenile leaves. Finally, gene co-expression network analysis revealed a module of co-expressed genes with differential gene expression linked to 5-azaC treatment in juvenile roots, pointing toward activation of genes associated with transposable elements. These results show how experimental treatment with 5-azaC at seed stage has both short and long-term effects in the plant transcriptome, potentially broadening phenotype variation due to nondirectional effects of 5-azaC on gene expression., This study was supported by the Spanish Ministerio de Ciencia, Innovación y Universidades, through the “Proyectos de I+D+i” program, with references PID2019-104365GB-I00 and PID2022-141530NB-C22. We acknowledge support of the publication fee by the CSIC through its Open Access Publication Support Initiative developed by the Unit of Information Resources for Research (URICI)., Peer reviewed