An early evaluation of translocation actions for endangered plant species on Mediterranean islands

In situ conservation is widely considered a primary conservation strategy. Plant translocation, specifically, represents an important tool for reducing the extinction risk of threatened species. However, thus far, few documented translocations have been carried out in the Mediterranean islands. The CareMediflora project, carried out on six Mediterranean islands, tackles both short-and long-term needs for the insular endangered plants through in situ and ex situ conservation actions. The project approach is based on using ex situ activities as a tool to improve in situ conservation of threatened plant species.Fifty island plants(representing 45 taxa) were selected for translocations using common criteria.During the translocations, several approaches were used, which differed in site selection method, origin of genetic material, type of propagative material, planting method, and more. Although only preliminary data are available, some general lessons can be learned from the experience of the CareMediflora project. Among the factors restricting the implementation of translocations, limited financial resources appear to be the most important. Specific preliminary management actions, sometimes to be reiterated after translocation, increase the overall cost, but often are necessary for translocation success. Translocation using juvenile/reproductive plants produces better results over the short term,although seeds may provide good results over the long run(to be assessed in the future). Regardless,plant translocation success can only be detected over long periods; therefore, proper evaluation of plant translocations requires a long-term monitoring protocol. Care-Mediflora project represents the first attempt to combine the existing approaches in a common plant conservation strategy specifically focusing on the Mediterranean islands.

What is a tree in the Mediterranean Basin hotspot?A critical analysis

Background: Tree species represent 20% of the vascular plant species worldwide and they play a crucial role in the global functioning of the biosphere. The Mediterranean Basin is one of the 36 world biodiversity hotspots, and it is estimated that forests covered 82% of the landscape before the first human impacts, thousands of years ago. However, the spatial distribution of the Mediterranean biodiversity is still imperfectly known, and a focus on tree species constitutes a key issue for understanding forest functioning and develop conservation strategies. Methods: We provide the first comprehensive checklist of all native tree taxa (species and subspecies) present in the Mediterranean-European region (from Portugal to Cyprus). We identified some cases of woody species difficult to categorize as trees that we further called "cryptic trees". We collected the occurrences of tree taxa by"administrative regions", i.e. country or large island, and by biogeographical provinces. We studied the species-area relationship, and evaluated the conservation issues for threatened taxa following IUCN criteria. Results: We identified 245 tree taxa that included 210 species and 35 subspecies, belonging to 33 families and 64 genera. It included 46 endemic tree taxa (30 species and 16 subspecies), mainly distributed within a single biogeographical unit. The countries with the highest tree richness are Greece (146 taxa), Italy (133), Albania (122), Spain (155), Macedonia (116), and Croatia (110). The species-area relationship clearly discriminated the richest central-eastern (Balkans) and northern (Alpine and Cevenno-Pyrenean) biogeographical provinces, against the five western provinces in the Iberian Peninsula. We identified 44 unrecognized "cryptic trees", representing 21% of the total trees. Among the 245 taxa identified, 19 are considered to be threatened (15 CR+EN+VU) or near threatened (4 NT) by IUCN. Conclusions: The Mediterranean-European region includes an unsuspectedly high number of tree taxa, almost 200 tree taxa more than in the central European region. This tree diversity is not distributed evenly and culminates in the central-eastern part of the Mediterranean region, whereas some large Tyrrhenian islands shelter several narrow endemic tree taxa. Few taxa are recognized as threatened in the IUCN Red list, and the vulnerability of these species is probably underestimated.

Sequential temperature control of multi-phasic dormancy release and germination of Paeonia corsica seeds

Aims The physiological responses during dormancy removal and multi-phasic germination were investigated in seeds of Paeonia corsica(Paeoniaceae).Methods Seeds of P.corsica were incubated in the light at a range of temperatures(10-25 and 25/10℃),without any pre-treatment,after W(3 months at 25℃),C(3 months at 5℃)and W+C(3 months at 25℃followed by 3 months at 5℃)stratification,and a GA_(3)treatment(250 mg·l^(−1)in the germination substrate).Embryo growth,time from testa to endosperm rupture and radicle emergence were assessed as separate phases.Epicotyl-plumule emergence was evaluated incubating the germinated seeds at 15℃for 2 weeks,at 5 and 25℃for 2 months on agar water before transplanting to the soil substrate at 10,15 and 20℃and at 15℃for 2 months on the surface agar water with GA_(3).Important Findings Embryo growth,testa rupture,endosperm rupture(radicle emergence)and growth of the epicotyl were identified as four sequential steps in seeds of P.corsica.Gibberellic acid alone and warm stratification followed by 15℃promoted embryo growth and subsequent seed germination.Cold stratification induced secondary dormancy,even when applied after warm stratification.After radicle emergence,epicotyl-plumule emergence was delayed for ca.3 months.Mean time of epicotyl-plumule emergence was positively affected by cold stratification(2 months at 5℃)and GA_(3).P.corsica seeds exhibited differential temperature sensitivity for the four sequential steps in the removal of dormancy and germination processes that resulted in the precise and optimal timing of seedling emergence.