bioRxiv Science⌕ Search

Biology subjects

Kuprina, K.

Publications and source records attributed to Kuprina, K..

6 recordsLinked to original sources

Less is more? Faster growth is associated with lower ectomycorrhizal diversity in mature Picea glauca at the Alaskan treelines

Root-associated fungal (RAF) communities can influence tree nutrition and performance, yet their environmental drivers and relationship with tree growth remain poorly understood, particularly near treelines. We characterized RAF communities, with a focus on ectomycorrhizal (ECM) fungi, associated with fine roots of white spruce (Picea glauca [Moench] Voss) across paired forest and treeline plots representing two elevational and one drought-limited treeline ecotones in Alaska. Using ITS2 DNA metabarcoding, we assessed fungal community composition and alpha diversity and related these metrics to basal area increment (BAI) over 5-30 years for individual trees. Sampling site was the strongest predictor of RAF community composition, explaining 19.6% of variation, followed by soil pH (11.7%), whereas habitat explained only 2.1%. Treeline effects were context-dependent: RAF composition differed between forest and treeline only in the Alaska Range, alpha diversity was lower at the treeline in Interior Alaska, and ECM relative abundance was higher at the Brooks Range treeline. In contrast, RAF community composition did not differ between fast- and slow-growing trees within sites. Interestingly, alpha diversity indices were significantly associated with BAI over the previous 5, 10 and 15 years, with lower diversity associated with faster tree growth. These relationships weakened with increasing BAI averaging period. Our results indicate that, in mature P. glauca, tree growth is associated with lower RAF and ECM diversity but not with distinct fungal community composition, suggesting that growth may be linked to greater dominance by a subset of fungal partners rather than higher fungal diversity.

ecology↗

Population genomics reveals divergent lineages in the European peatland plant Drosera rotundifolia

Genomic variation within populations reflects both past and contemporary evolutionary processes. The genetic structure of the European peatland plant species is shaped by complex postglacial recolonization and recent habitat loss. Here, we investigate population genomic patterns in the vulnerable mire plant, round-leaved sundew (Drosera rotundifolia L.). Using ddRAD sequencing of 311 individuals from 38 populations across Europe, we detected significant genetic differentiation (Fst = 0.02-0.44, p < 0.05) and a consistent deficit of heterozygosity (Fis = 0.248) across populations. In contrast, sequencing of 10,449 bp of chloroplast DNA revealed extremely low variation, with only one SNP detected. Clustering analyses (Admixture and DAPC) both identified pronounced genetic structure comprising three major clusters (Western, Northern, and Eastern) that broadly correspond to European biogeographic regions. Genetic differentiation was partially explained by geographic distance (3.3%; p = 0.0001; Mantel test), while climatic variables, particularly temperature and precipitation, accounted for 2.9% of genomic variation (p < 0.0001; redundancy analysis). The observed pattern is consistent with polygenic responses to climatic gradients and is supported by 1,022 SNPs, distributed across 632 loci, that were significantly associated with environmental variables. Demographic reconstruction revealed distinct evolutionary trajectories among clusters, with the Western cluster showing a more recent expansion. Together, our results suggest that the genetic structure of D. rotundifolia is a result of postglacial recolonization, geographic isolation, and climate influence. We highlight the importance of conserving genetic diversity of D. rotundifolia across all three clusters and accounting for potential local adaptation and population vulnerability in future conservation strategies.

evolutionary biology↗

How drought and ploidy level shape gene expression and DNA methylation in Phragmites australis

Drought stress significantly affects plant physiology and growth, yet the molecular mechanisms underlying drought responses remain poorly understood. In this study, we investigate how tetraploid and octoploid Phragmites australis (common reed), a key species in wetland ecosystems and paludiculture, respond to drought at the transcriptional and epigenetic levels. Using RNA-seq, we identify changes in gene expression after 20 and 30 days of drought and assess methylation-sensitive amplification polymorphism (MSAP) over 50 days of drought. Transcriptomic analysis reveals that key drought-response genes are shared between ploidy levels, including those involved in the saccharopine pathway, water deprivation response, cell wall remodelling, and the mevalonate pathway. Drought supresses photosynthesis, with a pronounced down-regulation of the photosynthetic gene PsbP. Ploidy level influences gene expression under both drought and non-stress conditions, highlighting distinct adaptive strategies. In control samples, gene expression differed between ploidy levels, with octoploids up-regulating genes related to translation and metabolism, while tetraploids activate genes involved in cell wall modification and transmembrane transport. Prolonged drought increases DNA methylation variability, though no significant correlation is found between methylation levels and drought duration. Methylation differences are more pronounced between ploidy levels, with octoploids exhibiting lower overall methylation. These findings highlight the complex interactions between gene expression, epigenetic modifications, and polyploidy in drought response and provide a theoretical framework for future selection, hybridization, and conservation initiatives. Main ConclusionKey drought-response genes regulate saccharopine and mevalonate pathways, and cell wall remodelling. Ploidy level influences gene expression under drought and non-stress conditions. Octoploids overall exhibit lower methylation than tetraploids.

ecology↗

Higher ploidy coincides with inferior performance and no difference in stress tolerance in reed

(1) Climate change leads to more extreme weather events. Therefore, a high stress tolerance is becoming more critical for plants, with higher ploidy being reported to lead to higher stress tolerance. Phragmites australis (P. australis) is a target species for paludiculture, i.e. the wet use of peatlands, and well known for its many ploidy levels. (2) We expected octoploid genotypes of P. australis to outperform tetraploid ones in a 15-month mesocosm experiment including a gradient of 0 to 100 days of drought. We used pairs of genotypes differing in ploidy from three different geographic regions. (3) Increasing drought length led to a decrease in growth, biomass, morphological and ecophysiological traits in both ploidy levels, but 4x outperformed 8x in almost all traits under constant water supply (e.g., 2.5-fold more biomass production) and up to moderate drought (about 50 days). Under severe and prolonged drought, both ploidy levels performed equally poorly. (4) Our study suggests that higher ploidy levels do not necessarily outperform lower ploidy levels of P. australis under stressful conditions. In this species, ploidy alone may not explain performance, but the genotype can be as or more important than ploidy.

ecology↗

Phylogenetically distant but cohabiting: Fungal communities of fine roots in Diphasiastrum complanatum, Pinus sylvestris, and Vaccinium myrtillus in a Lithuanian pine forest

Throughout evolution, distinct plant lineages independently established mutualistic relationships with various fungal taxa. However, the extent to which these relationships are conserved across different plant and fungal lineages remains unclear. In this study, we compared fungal communities associated with the fine roots of three phylogenetically distant yet cohabiting plant species: Diphasiastrum complanatum, a member of lycophytes, the most basal extant vascular plant lineages; Pinus sylvestris, a gymnosperm; and Vaccinium myrtillus, an angiosperm, an evolutionary relatively young lineage. To minimize environmental variability, fine roots of three species were collected from each of 19 five-square-meter plots within a Scots pine forest in Lithuania. Using metabarcoding and microscopic techniques, we observed significant differences in the fungal community composition and diversity among the three plant species. We detected no signs of arbuscular mycorrhiza in any species. Samples of D. complanatum showed significantly higher taxonomical diversity, while P. sylvestris showed lowest diversity, with ectomycorrhizal fungi being most abundant. Samples of V. myrtillus had a prevalence of putative ericoid mycorrhiza taxa, classes Sebacinales and Trechisporales, likely forming hyphal coils detected through microscopy. In contrast, no mycorrhiza was detected in D. complanatum sporophytes. This, along with the presence of well-developed root hairs and similarity to the fungal community inhabiting soil suggests a low dependency on mycorrhizal associations and a more opportunistic fungi-plant relationship. This is the first study of fungi associated with the sporophytes of D. complanatum. Our findings provide valuable insights into the complex interactions between fungi and plants from diverse phylogenetic lineages in natural environments.

ecology↗

Genetic diversity and fine-scale structure of two populations of a subterranean rodent, Ellobius talpinus

Subterranean rodents represent an interesting model system for molecular ecologists. Their lifestyle is associated with fragmented environments, limited dispersal ability, and low fecundity. These characteristics all are expected to increase inter- and intrapopulation differentiation and reduce intra- population genetic diversity, yet the published empirical data revealed the lack of generality of this pattern. This emphasizes the importance of accumulating more data on individual species to understand what factors shape the genetic dynamics of populations. This study represents the first characterization of the population genetic diversity and fine-scale genetic structure of a highly specialized subterranean vole, Ellobius talpinus. We used nine microsatellite loci and a fragment of the mitochondrial D-loop to investigate genetic patterns of two distant populations: the Novosibirsk population at the extreme northeastern edge of the species range, and the sub-peripheral Saratov population. As a result, the two populations exhibit distinct patterns of genetic structure. The Novosibirsk population showed a low nuclear diversity with an observed heterozygosity (Ho) of 0.34 and an unbiased expected heterozygosity (uHe) of 0.55. Mitochondrial D-loop was nearly monomorphic with over 90% of the observed haplotypes being identical, resulting in a haplotype diversity (Hd) of 0.14 and nucleotide diversity ({pi}) of 0.0004. In contrast, the Saratov population displayed moderate nuclear (Ho = 0.64; uHe = 0.76) and high mitochondrial variation (Hd = 0.83;{pi} = 0.034), compared to the surface-dwelling voles. Nine haplotypes representing four well-differentiated mitochondrial clades were found in the Saratov population. In a heterogeneous landscape, significant genetic differentiation was revealed at both intermediate (dozens of kilometers) and fine (several kilometers) scales. However, within the continuous suitable habitat, no fine-scale spatial structure was observed apart from that caused by kin clustering. The spatial genetic patterns revealed in E. talpinus appear to reflect a combination of effects of strong social structure, local natural and anthropogenic barriers limiting dispersal opportunities, and occasional long-distance dispersal.

zoology↗