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Worldwide about one third of all plant species is estimated to be threatened with extinction. Plants are generally under-represented in conservation. However, the global strategy for plant conservation (GSPC) sets forth 16 targets to halt the current and continuing loss of plant diversity within a framework for actions at global, regional, national and local levels. Target 8 of the GSPC directs that at least 75 % of threatened plant species be present in ex situ collections by 2020, but this target is far from being met. By analyzing where gaps in ex situ collections and research exist relative to diversity hotspots of threatened species, it is possible to identify and prioritize action. We undertake a gap analysis of ex situ collection needs in the genus Magnolia, a relatively well-known and valuable genus. Results indicate three main areas of biodiversity (China, Vietnam and Colombia) for the endangered Magnolia taxa. The present paper provides a critical overview of recent conservation activities carried out in the genus Magnolia throughout the world, focusing on genetic diversity analyses of the species

The aim of this study was to assess genome size variation and multivariate morphometric analyses to ascertain cytotype distribution patterns and the morphological differentiation within the Ranunculus parnassifolius group in the Pyrenees and the Alps. Although divergences in nuclear DNA content among different species within a genus are widely acknowledged, intraspecific variation is still a somewhat controversial issue. Holoploid and monoploid genome sizes (C-and Cx-values) were determined using propidium iodide flow cytometry in 125 plants of R. parnassifolius s.l. distributed across four European countries. Three different DNA ploidy levels were revealed in the study area: diploid (2n~2x, 57.14%), triploid (2n~3x, 1.19%), and tetraploid (2n~4x, 41.67%). The mean population 2C-values ranged from 8.15 pg in diploids to 14.80 pg in tetraploids, representing a ratio of 1 : 1.8. Marked intraspecific/interpopulation differences in nuclear DNA content were found. Diploid populations prevail in the Pyrenees, although tetraploid cytotypes were reported throughout the distribution area. In general, mixed-cytotype populations were not found. The Spearman correlation coefficient did not reveal significant correlations between genome size and altitude, longitude, or latitude. Morphometric analyses and cluster analyses based on genome size variation revealed the presence of three major groups, which exhibited a particular biogeographical pattern. A new cytotype, DNA triploid, was found for the first time. Tetraploid populations showed constant nuclear DNA levels, whereas diploid populations from the Pyrenees, in which introgressive hybridization is suggested as a presumable trigger for genome size variation, did not. Scenarios for the evolution of geographical parthenogenesis in R. parnassifolius s.l. are discussed. Finally, the different levels of effectiveness between plant and animal reference standards are analysed.

Microsatellite variation at the nuclear and chloroplast genomes was evaluated for wild European and wild American hops, in order to assess the genetic diversity and origin of cultivated hops. Seven nuclear loci and 32 chloroplast loci were used in the analysis of 182 hop accessions including wild European (68), wild American (48), and cultivars (66). A total of 116 alleles were identified using 7 nuclear microsatellites showing different averages of polymorphism and distribution in the wild American and European accessions and cultivars. Two main groups were established as revealed by several statistical analyses; one including European wild accessions and cultivars and a second group consisting of American wild accessions. Three polymorphic chloroplast microsatellite loci were detected, six alleles were scored which defined a total of five haplotypes that were exclusive or presented different distribution between American and European wild accessions. A major influence of the wild European haplotypes was detected among hop cultivars. To the best of our knowledge, this is the first work reporting the use of chloroplast microsatellites in hops.

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