Reproductive efficiency of Primula allionii: is this endemic plant really threatened?

Primula allionii is a primrose endemic to Maritime Alps. The plant was studied in three different plots representing the different structures of cliffs where the species usually lives. The reproductive success of the plant was analyzed in order to evaluate its conservation status. Mean plant dimensions and distribution within the plots were evaluated. The species resulted low morph biased (0.13), very fertile (83.53%) and with a quite good sexual organs efficiency of flowers (both in pin and thrum morphs) as demonstrated by the high rate of fruit (52.18%) and seed production (20-50% ovules developed in seeds). However, the populations remain in a demographic balance ( % = 0.38) and very few seedlings (0.21% of available seeds) were recorded in populations. The particular habitat of the plant does not favour a consistent population renewal. Primula allionii populations are not under a real threat at present: but the species and its loci deserve much more consideration in the future in order to preserve this possibly fragile habitat

Knowing the past to forecast the future: a case study on a relictual, endemic species of the SW Alps, Berardia subacaulis

Future climate change may lead to a substantial loss of biodiversity, particularly affecting mountain regions, including the Alps. Range-size reduction in high mountain plant species is predicted to be more pronounced for endemic species. Investigating the broad temporal spectrum of range shifts is important for the conservation of biodiversity, since learning how species responded to climate change in the past provides useful insights on how they might react to warming trends in the present and future. Using species distribution models and an ensemble forecasting approach, we explored how the distribution of Berardia subacaulis, a monospecific genus endemic of the south-west Alps, may be affected by past and future projected climate change. During the last interglacial, the habitat suitability of Berardia was lower than present and a progressive increase was observed from the last glacial maximum until now. In the future, Berardia appears to lose more than 80 % of its range, becoming endangered by 2050. Our results suggest that Berardia probably survived past warmer periods in situ, expanding its distributional range during cooler periods. The severe future range contraction predicted for Berardia reflects similar results for other endemic species. As Berardia represents an interesting model species to evaluate the effects of climate warming on range size and shifts, demographic and precise range monitoring may be undertaken on this species

First evidence of post‐glacial contraction of Alpine endemics: Insights from Berardia subacaulis in the European Alps

Aim: Late Quaternary glaciations left an enduring imprint on the distribution of species and their genetic structure. The responses of plants endemic to the Alps can be summarized in three major demographic hypotheses: (i) post-glacial expansion hypothesis; (ii) post-glacial contraction hypothesis; and (iii) long-term stability hypothesis. Here we test these hypotheses and reconstruct the time and extent of demographic responses of an endemic plant to the Late Quaternary climate dynamics. Location: European Alps. Taxon: Berardia subacaulis Vill. (Asteraceae). Methods: We used species distribution models to estimate the paleodistribution of B. subacaulis (Asteraceae) throughout the last 28 Ky and generated genome-wide sequences to estimate current patterns of spatial structure of genetic diversity. We tested five demographic models by integrating the results of the two independent approaches in an Approximate Bayesian Computation framework. Results: The species has weak genetic differentiation among populations, with two main genetic groups. Species distribution models showed a reduction in potentially suitable areas for B. subacaulis during the post-glacial climate warming and demographic models identified a recent split (2.46 Kya) between the two genetic groups and they slightly supported the post glacial contraction hypothesis. Main conclusions: Taken together, our results support the post-glacial contraction of an endemic plant, differing from the main pattern observed for endemics species in the European Alps during the Late Quaternary. The different pattern observed in B. subacaulis might be due to several factors, including the less severe effects of glaciations and the environmental heterogeneity of the South Western Alps, combined with some features of the species (i.e. poor dispersal ability, slow growth and microhabitat preferences). Future research in areas where the ice cover was less extensive will contribute to a more complete understanding of the role of climatic changes in shaping the endemics of the European Alps

First evidence of post‐glacial contraction of Alpine endemics: Insights from Berardia subacaulis in the European Alps

International audienceAim: Late Quaternary glaciations left an enduring imprint on the distribution of species and their genetic structure. The responses of plants endemic to the Alps can be summarized in three major demographic hypotheses: (i) post-glacialexpansion hypothesis; (ii) post-glacial contraction hypothesis; and (iii) long-term stability hypothesis. Here we test these hypotheses and reconstruct the time and extent of demographic responses of an endemic plant to the Late Quaternary climate dynamics.Location: European Alps.Taxon: Berardia subacaulis Vill. (Asteraceae).Methods: We used species distribution models to estimate the paleodistribution of B. subacaulis throughout the last 28 Ky and generated genome-wide sequences to estimate current patterns of spatial structure of genetic diversity. We tested five demographic models by integrating the results of the two independent approaches in an Approximate Bayesian Computation framework.Results: The species has weak genetic differentiation among populations, with two main genetic groups. Species distribution models showed a reduction in potentially suitable areas for B. subacaulis during the post-glacial climate warming and demographic models identified a recent split (2.46 Kya) between the two genetic groups and they slightly supported the post glacial contraction hypothesis.Main conclusions: Taken together, our results support the post-glacial contraction of an endemic plant, differing from the main pattern observed for endemics species in the European Alps during the Late Quaternary. The different pattern observed in B.subacaulis might be due to several factors, including the less severe effects of glaciations and the environmental heterogeneity of the South Western Alps, combined with some features of the species (i.e. poor dispersal ability, slow growth and microhabitatpreferences). Future research in areas where the ice cover was less extensive will contribute to a more complete understanding of the role of climatic changes in shaping the endemics of the European Alps

The plant endemism in the Maritime and Ligurian Alps

The Maritime and Ligurian Alps have a flora characterised by a very high number of endemic species in relation to their small geographical extension. This area is considered one of the most important centres of diversification of the Alps and a Mediterranean hotspot of biodiversity. In the last years many studies were performed in order to describe the distribution and phylogeographical patterns of endemism. Despite these studies, Maritime and Ligurian Alps still lack in a broad view about the evolution of endemisms in this area. In this review, we examine the knowledge about the distribution patterns of endemic plant species living in the Maritime and Ligurian Alps in order to identify the evolutionary and biogeographical mechanisms operating on them

Reproductive biology of the threatened Lilium pomponium (Liliaceae), a species endemic to Maritime and Ligurian Alps

Pollination ecology and breeding system of Lilium pomponium L. were studied, and their effect on the reproductive outcome was assessed. This species has high conservation interest in Europe, because it is included in Annex V of the EU Habitat Directive and it is one out of the five Lilium species listed in IUCN Global Red List. To achieve our aim, the pollen vectors as well as the effect of bagging, emasculation and artificial pollination on reproductive output were studied. The most frequent visitor was the Lepidopteran Gonepteryx rhamnii. In general, reproductive outputs were close to zero for all the self-pollination treatments; however, geitonogamy and facilitated selfing seem slightly more efficient than autogamy, as also confirmed by self-compatibility and autofertility indices. Altogether, our results suggest a self-incompatible outcrossing breeding system, with a poor capacity for selfing. Nevertheless, climate change and anthropic threats might promote a shift toward self-fertilization, even maladaptive, favouring the few individuals able to produce selfed seeds

The plant endemism in the Maritime and Ligurian Alps

The Maritime and Ligurian Alps have a flora characterised by a very high number of endemic species in relation to their small geographical extension. This area is considered one of the most important centres of diversification of the Alps and a Mediterranean hotspot of biodiversity. In the last years many studies were performed in order to describe the distribution and phylogeographical patterns of endemism. Despite these studies, Maritime and Ligurian Alps still lack in a broad view about the evolution of endemisms in this area. In this review, we examine the knowledge about the distribution patterns of endemic plant species living in the Maritime and Ligurian Alps in order to identify the evolutionary and biogeographical mechanisms operating on them

Phylogeography of Primula allionii (Primulaceae), a narrow endemic of the Maritime Alps

Primula allionii is endemic to a tiny area of the Maritime Alps and has one of the narrowest distribution ranges in this hotspot of biodiversity. Phylogeographical patterns in P. allionii were studied using plastid DNA markers and dominantly inherited markers (AFLP and ISSR) to verify any admixture between P. allionii and the sympatric P. marginata and to detect the phylogeographical history of the species. Morphometric measurements of flowers and admixture analysis support the hypothesis that hybridization occurs in nature. Species distribution models using two climate models (CCSM and MIROC) suggested a reduction in habitat suitability during cold periods. Phylogeographical analysis suggested an old allopatric divergence during the mid-Pleistocene transition (about 0.8 Mya) without recolonization/contraction cycles. The Alps watershed does not act as a strong barrier between the two main areas of the distribution range, and moderate gene flow by pollen seems to create the admixture recorded among the stands. According to our results, the persistence of P. allionii throughout the Ice Age appears to be linked to the capacity of the Maritime Alps to provide a wide diversity of microhabitats consistent with the recent biogeographical pattern proposed for the Mediterranean Basin

Pollination ecology in the narrow endemic winter-flowering Primula allionii (Primulaceae)

none6Reduction of pollen flow can affect plant abundance and population viability and cause selection on plant mating system and floral traits. Little is known on the effect of this phenomenon in species naturally restricted to small and isolated habitats, that may have developed strategies to cope with long-term isolation and small population size. We investigated the pollination ecology of the endemic distylous winter-flowering P. allionii to verify the possible limitation of female fitness due to reduced pollinator visits. We recorded a higher production of pollen grains in long-styled morph, and a higher seed set in shortstyled morph. The high intra-morph variability of sexual organ position may explain the hybridization phenomena allowing and easier intra-morph pollination. The fruit set is constant, although its winter-flowering period might decrease pollen transfer. Nevertheless, the lower competition for pollinators with neighbouring plants and the longlasting anthesis may offset its reproductive success. Even if our results show no evidence of imminent threats, changes in plant–pollinator interactions might increase inbreeding, resulting in an increased extinction risk.openMINUTO L.; GUERRINA M.; ROCCOTIELLO E.; ROCCATAGLIATA N.; MARIOTTI M.G.; CASAZZA G.Minuto, Luigi; Guerrina, Maria; Roccotiello, Enrica; Roccatagliata, N.; Mariotti, Mauro; Casazza, Gabriel

Management of an invasive plant in a mediterranean protected area: the experience of Senecio deltoideus in Italy

International audienceBiological invasions are one of the most serious threats to global biodiversity and ecosystem integrity. The problem is growing year by year and a large number of protected areas worldwide are today invaded by at least one exotic species. In this study, we tested the eco-friendly and cost-effective weeding control of Senecio deltoideus in a Regional Protected Area in the North Mediterranean region. During a two years experiment, four techniques compatible with the local laws on protected areas (natural-herbicide, flame-weeding, mulching and mowing) were applied five times a season on sixty plots, compared with fifteen untreated controls. All techniques were effective in reducing Senecio covering: after the first year the maximum covering was limited to 37.93% (flame weeding) with a mean value of 10%; after second year the covering was further reduced (17.02% max; 2% mean). Interestingly, during the second year all plots submitted to a one-year treatment showed an enduring control of S. deltoideus covering (40.73% max; 20% mean). Taking into account feasibility and their impact on the environment, the weeding control recommendable for S. deltoideus is mowing. In a long-time management strategy, the selected treatment could be applied every two years with a drastic reduction in costs for the manager of the protected area