Biology subjects

Roncoroni, M.

Publications and source records attributed to Roncoroni, M..

5 recordsLinked to original sources

bioRxiv2026

Salmonid science on the move: Twenty years of research through the lens of early career researchers

Salmonids are among the most studied fish species worldwide, owing to their wide geographic distribution, diversity of life-history strategies, ecological and socioeconomic importance, and vulnerability to global change. In this review, we take advantage of two decades of the International Workshop of PhDs and Post-doctoral Fellows on Anadromous Salmonids (NoWPaS) conference series to track the evolution of salmonid science through the lens of early-career researchers (ECRs). From all abstracts presented at NoWPaS meetings between 2005 and 2025, we extracted structured qualitative and quantitative information to characterize major trends and shifts in the field. Our results show a strong research bias toward Atlantic salmon and brown trout, concentrated in Europe and Atlantic Canada, and a persistent mismatch between the life stages and habitats studied. In particular, the marine phase remains understudied in comparison to fresh and coastal waters. Over the study period, salmonid research shifted markedly from hydro-geomorphological and habitat-based approaches toward genetic and genomic methods, alongside the rise of advanced telemetry methods for reconstructing individual life histories. Research orientation, measured as a gradient from fundamental to applied research, was on average intermediate but varied among countries and disciplines, with the UK and Norway showing shifts to more applied research, as well as the discipline of Ecology becoming more applied. Additionally, we identified a significant increase in Climate change and Aquaculture as research drivers, with some drivers well-represented in some species (e.g., Hydropower and dams for landlocked Atlantic salmon and Climate change for Arctic char). These trends should be interpreted in context of the composition of the NoWPaS network: participation is primarily ECRs in the Northern Hemisphere, with research from Asia, South America, and western North America largely absent from this synthesis. Despite this lens, our analysis identifies clear knowledge gaps, particularly around marine life stages and species other than Atlantic salmon and brown trout, and highlights opportunities for broadening taxonomic, geographic, and life-history coverage in future salmonid research. We also present a roadmap, identifying combinations of life stages, disciplines and taxa which have been under-represented and constitute potential knowledge gaps, while also flagging those combinations that have already been well studied. Overall, we advocate for a continued shift toward integrative and holistic approaches, bridging distinct research disciplines, to better understand, manage, and conserve salmonids under increasingly uncertain future environmental conditions.

ecology↗

bioRxiv2025

Use of massive DNA barcoding to monitor biodiversity: a test on forest soil fauna

Biodiversity monitoring primarily focuses on particular taxonomic groups for which identification expertise is widely available, such as vascular plants or birds. As a result, the response of many taxonomic groups to forest management is much less documented. With the advent of low-cost next generation barcoding approaches, it is now possible to envisage monitoring strategies based on molecular approaches, beyond metabarcoding/eDNA strategies that do not give access to species abundances and integrate species presence over largely unknown spatio-temporal scales. In this contribution, we demonstrate the use of massive DNA barcoding - also referred as megabarcoding - as a promising solution to overcome identification difficulties in demanding taxonomic groups. We performed a proof of concept study in a mountainous beech forest in the Massif Central, France. We sampled soil macrofauna at 25 sampling sites and managed to visually identify at the species level 130 out of the 1413 sampled individuals. Using megabarcoding on the 1283 remaining non-identified individuals, we managed to assign 1124 additional individuals to an operational taxonomic species at a competitive cost. We present the summary statistics of barcoding success in the different taxonomic groups encountered and in larvae versus adult individuals. We demonstrate that larvae individuals, which can hardly be visually identified at the species level, make a substantial contribution to overall macrofauna diversity. We finally showcase how this megabarcoding approach provides a concrete avenue for forest biodiversity monitoring, by assessing the cost and labour intensity of this approach.

ecology↗

bioRxiv2023

Environmental variables and species traits as drivers of wild bee pollination in intensive agroecosystems -a metabarcoding approach

Wild bees are known to be efficient pollinators of wild plants and cultivated crops and they are essential ecosystem service providers. However, wild bee populations have been suffering from significant declines in the last decades mainly due to the use of agrochemicals. Within this framework, we aimed to characterize wild bees pollination spectrum (i.e. the community of pollinated flowering plants) in intensive agroecosystems, and describe the environmental variables and wild bee species traits influencing the pollination. To do this, we conducted metabarcoding analyses of pollen loads from wild bees collected in sunflower crops in the French region of Nouvelle-Aquitaine. Our study revealed that wild bees visited flowering plants corresponding to 231 different Operational Taxonomic Units, classified in 38 families of which Asteraceae, Brassicaceae and Apiaceae were the most visited and more than 90% of the visited taxa turned out to be wild flowers. We also analysed the potential effect of environmental variables and wild bee species traits in governing their choice of pollinated plants. The community composition of pollinated plants varied depending on the flowering stages of the sunflower and the farming system. Our results also show that pollination niche breadth (alpha diversity) varied depending on the flowering stages of the sunflower but was not different between organic and conventional farming systems. Regarding wild bee species traits, the community composition of pollinated plants varied in relation to wild bees body sizes and, sociality levels. Our results are consistent with previous studies, suggesting that solitary bees are more specialists when it comes to flower selection than social bees, which are more generalist. The metabarcoding of pollen loads enabled us to draw a global picture of plant-wild bee interactions in an intensive agroecosystem. Our findings support the hypothesis that a higher diversity of weeds may increase wild bee diversity in intensive agroecosystems.

ecology↗

bioRxiv2021

Functional traits of carabid beetles reveal seasonal variation in community assembly in annual crops

O_LITrait-based community assembly studies have mostly been addressed along spatial gradients, and do not consider explicitly a fundamental dimension governing community assembly, the time. Nevertheless, such consideration seems particularly necessary in systems in which organisms have to face regular disturbances and rapid changes in vegetation phenology, such as in intensively managed farmlands. C_LIO_LIIn this study, we aimed at understanding how the functional diversity of carabid beetle communities varied across the growing season in response to crop type. We tested three alternative hypotheses on mechanisms underlying the community assembly. C_LIO_LIWe used data from a long-term monitoring conducted over nine years in an intensively-managed farmland in central western France, in a total of 625 fields. First, we measured morphological traits related to body size, dispersal mode, and resource acquisition on the 13 dominant carabid species (> 85 % of all trapped individuals) and identified three independent dimensions of functional specialization within our species pool along axes of a PCA and highlighted key traits for community assembly. Second, we evaluated the community assembly temporal dynamics and the impact of habitat filtering and niche differentiation in the different crop types with time, using linear mixed-effects models. C_LIO_LIWe showed that functional species assembly of carabid beetle communities occurring in crop fields varies importantly intra-annually, with strong variations in these dynamics depending on crop type and crop phenology. Each crop acted as a filter on carabid communities for body size and resource-acquisition traits, and functional differentiation between crops increased with time. We did not find any evidence of habitat filtering on traits related to dispersal mode. C_LIO_LIOur results emphasize the major role of crop phenology but also disturbances involved by agricultural practices such as crop harvesting on changes in community assembly, likely due to seasonal and inter-annual redistributions of species in agricultural landscapes in response to such changes. The temporal dimension cannot be ignored to understand the assembly of local carabid communities in farmlands. C_LI

ecology↗

bioRxiv2018

A study of phenotypic plasticity of Saccharomyces cerevisiae in natural grape juices shed light on allelic variation under balanced selection.

The ability of a genotype to produce different phenotypes according to its surrounding environment is known as phenotypic plasticity. Within different individuals of the same species, phenotypic plasticity can vary greatly. This contrasted response is due to allelic variations and is caused by gene-by-environment interactions (GxE). Finding the genes and the cellular functions that interact with the environment is a current challenge for better understanding the genetic bases of phenotypic plasticity. In order to study the impact of natural allelic variations having a contrasted but relevant effect in a changing environment, we investigated the phenotypic response of the wine yeast Saccharomyces cerevisiae fermented in various grape juices. In this study we implemented a QTL mapping program using two independent offspring (~100 progeny) in order to investigate the molecular basis of yeast phenotypic response in a wine fermentation context. Thanks to high throughput sequencing approaches, both populations were genotyped, providing saturated genetic maps of thousands of markers. Linkage analyses allowed the detection of 78 QTLs including 21 with significant interaction with the nature of the fermented juice or fermentation conditions. Molecular dissection of a major QTL showed that the sulfite pump Ssu1p has a pleiotropic effect and impacts the phenotypic plasticity of several traits. Both alleles have positive effect according to external condition in phenotypes related to yeast fitness suggesting an example of balanced selection. All together these results pave the way for exploiting and deciphering the genetic determinism of phenotypic plasticity.

genetics↗