Biology subjects

Brendel, O.

Publications and source records attributed to Brendel, O..

5 recordsLinked to original sources

bioRxiv2025

MYB59 is linked to natural variation of water use associated with warmer temperatures in Arabidopsis thaliana

Water-use contributes significantly to plant growth and productivity, yet the extent to which variation in water-use is a function of adaptive differentiation is unknown. Here, we studied natural variation of water use in Arabidopsis thaliana to understand how climatic history impacts water use strategies. We performed a survey of vegetative water use (VWU) and life-history traits across A. thaliana ecotypes in controlled and outdoor settings. Performance of select ecotypes in controlled experiments was reflective of performance in outdoor conditions. Through trait-climate and genome-wide association (GWAS) analyses, we tested for signals of environmental adaption in water use. Ecotypes from warmer environments were noted in displaying enhanced water use, independent of precipitation. GWAS identified MYB59 as a determiner of VWU. Functionally significant MYB59 SNPs showed associations with temperature, but not precipitation, and myb59 mutants demonstrated reduced water use under high temperatures. Our study suggests intraspecific variation in water-use can be explained in part by climatic history, where temperature is the most significant driver. MYB59 appears involved in this association and holds promise for study in crops.

plant biology↗

bioRxiv2023

Species-specific epigenetic responses to drought stress of two sympatric oak species reflect their ecological preferences.

O_LIIn a context of climate change, it is necessary to decipher the strategies established by plants to cope with limited water supply. C_LIO_LITranscriptome, methylome and small RNA data were generated for two oak species with contrasting levels of drought tolerance (Quercus robur and Quercus petraea), under control and drought stress conditions C_LIO_LIAll data are in line with a species-specific response to drought stress consistent with their ecological preferences. The biological processes associated with genomic regions identified in all datasets were mainly associated with parietal processes in Q. petraea, which may explain in part its better tolerance to water deprivation. C_LIO_LIA significant proportion of DNA methylation differences observed in control conditions between the two oak species were maintained during DS which may constitute a pool of epigenetic markers discriminating these two oak species. These markers were enriched in highly differentiated SNPs suggesting that some of them may be associated both with the ecological differences or intrinsic barriers to reproduction between the two species. C_LIO_LIAn integrative approach of the three datasets revealed genomic co-locations of potential importance for forest three adaptation to drought stress. C_LI

genomics↗

bioRxiv2021

Molecular plasticity to soil water deficit differs between sessile oak (Quercus Petraea (Matt.) Liebl.) high and low water use efficiency genotypes

BackgroundWater use efficiency (WUE) is an important adaptive trait for soil water deficit. The molecular and physiological bases of WUE regulation in crops have been studied in detail in the context of plant breeding. Knowledge for most forest tree species lags behind, despite the need to identify populations or genotypes able to cope with the longer, more intense drought periods likely to result from climate warming. ResultsWe aimed to bridge this gap in knowledge for sessile oak (Quercus Petraeae Matt. L.), one of the most ecologically and economically important tree species in Europe, using a factorial design including two genotypes (low and high WUE) and two watering regimes (control and drought). By monitoring the ecophysiological response, we were able to identify groups of genotypes with high and low WUE. We then performed RNA-seq to quantify gene expression for the most extreme genotypes exposed to two watering regimes. By analyzing the interaction term, we were able to capture the molecular strategy of each group of plants for coping with drought. Regardless of water availability, the high WUE genotypes overexpressed genes associated with drought responses, and the control of stomatal density and distribution, and displayed a downregulation of genes associated with early stomatal closure and high transpiration rate. High-WUE genotypes, thus, coped with drought by fine-tuning the expression of genes with known functions in the regulation of stomatal size, density, movement or aperture and transpiration rate. ConclusionFine physiological screening of sessile oaks with contrasting WUE, and their molecular characterization i) highlighted subtle differences in transcription between low and high WUE genotypes, identifying key molecular players in the genetic control of this trait, and ii) revealed the genes underlying the molecular strategy that had evolved in each group to cope with water deficit, providing new insight into the value of WUE for adaptation to drought.

plant biology↗

bioRxiv2021

Recovery of silver fir (Abies alba Mill.) seedlings from ungulate browsing mirrors soil nitrogen availability

Abies alba has a high potential for mitigating climate change in European mountain forests, yet, its natural regeneration is severely limited by ungulate browsing. Here, we simulated browsing in a common garden experiment to study growth and physiological traits, measured from bulk needles, using a randomized block design with two levels of browsing severity and seedlings originating from 19 populations across Switzerland. Genetic factors explained most variation in growth (on average, 51.5%) and physiological traits (10.2%) under control conditions, while heavy browsing considerably reduced the genetic effects on growth (to 30%), but doubled those on physiological traits related to C storage. While browsing reduced seedling height, it also lowered seedlings water use efficiency (decreased{delta} 13C) and N supply by mycorrhizal fungi as indicated by an increase in{delta} 15N. Different populations reacted differently to browsing stress, and for Height, Starch and{delta} 15N, population differences appeared to be the result of natural selection. We found that the fastest growing populations, originating from the warmest regions, decreased their needle starch level the most as a reaction to heavy browsing, suggesting a potential genetic underpinning for a growth-storage trade-off. Further, we found that seedlings originating from mountain populations growing on steep slopes had a significantly lower N discrimination in the common garden than those originating from flat areas, indicating that they have been selected to grow on N poor, potentially drained, soils. This finding was corroborated by the fact that N concentration in adult needles was lower on steep slopes than on flat ground, strongly indicating that steep slopes are the most N poor environments. Seedlings from these poor environments generally had a low growth rate and high storage, thus might be slower to recover from browsing stress than fast growing provenances from the warm environments with developed soils, such as the Swiss plateau.

evolutionary biology↗

bioRxiv2018

Non-functional and weak alleles of FRIGIDA and FLOWERING LOCUS C reduce lifetime water-use independent of leaf-level water-use-efficiency traits in Arabidopsis thaliana

Natural selection driven by water availability has resulted in considerable variation for traits associated with drought tolerance and leaf level water-use efficiency (WUE). In Arabidopsis, little is known about the variation of whole-plant water use (PWU) and whole-plant WUE (TE). To investigate the genetic basis of PWU, we developed a novel proxy trait by combining flowering time and rosette water use to estimate lifetime PWU. We validated its usefulness for large scale screening of mapping populations in a subset of ecotypes. This parameter subsequently facilitated the screening of water-use but also drought tolerance traits in a recombinant inbred line population derived from two Arabidopsis accessions with distinct water use strategies, namely C24 (low PWU) and Col-0 (high PWU). Subsequent quantitative trait loci (QTL) mapping and validation through near-isogenic lines identified two causal QTLs, which showed that a combination of weak and non-functional alleles of the FRIGIDA (FRI) and FLOWERING LOCUS C (FLC) genes substantially reduced plant water-use without penalising reproductive performance. Drought tolerance traits, stomatal conductance, intrinsic water use efficiency ({delta}13C) and rosette water-use were independent of allelic variation at FRI and FLC, suggesting that flowering is critical in determining life-time plant water use, but not leaf-level traits.

plant biology↗