Jonas V. Müller

Global conservation priorities for crop wild relatives

The wild relatives of domesticated crops possess genetic diversity useful for developing more productive, nutritious and resilient crop varieties. However, their conservation status and availability for utilization are a concern, and have not been quantified globally. Here, we model the global distribution of 1,076 taxa related to 81 crops, using occurrence information collected from biodiversity, herbarium and gene bank databases. We compare the potential geographic and ecological diversity encompassed in these distributions with that currently accessible in gene banks, as a means to estimate the comprehensiveness of the conservation of genetic diversity. Our results indicate that the diversity of crop wild relatives is poorly represented in gene banks. For 313 (29.1% of total) taxa associated with 63 crops, no germplasm accessions exist, and a further 257 (23.9%) are represented by fewer than ten accessions. Over 70% of taxa are identified as high priority for further collecting in order to improve their representation in gene banks, and over 95% are insufficiently represented in regard to the full range of geographic and ecological variation in their native distributions. The most critical collecting gaps occur in the Mediterranean and the Near East, western and southern Europe, Southeast and East Asia, and South America. We conclude that a systematic effort is needed to improve the conservation and availability of crop wild relatives for use in plant breeding.

Adapting agriculture to climate change: a global initiative to collect, conserve, and use crop wild relatives

The main objective of the“Adapting Agriculture to Climate Change” project is to collect and protect the genetic diversity of a portfolio of plants with the characteristics required for adapting the worlds most important food crops to climate change. The initiative also aims to make available this diversity in a form that plant breeders can readily use to produce varieties adapted to the new climatic conditions that farmers, particularly in the developing world, are already encountering. Such adaptation is a key component of securing the worlds future food production. This paper serves to inform interested researchers of this important initiative and encourage collaboration under its umbrella.

Plant regeneration from seeds responds to phylogenetic relatedness and local adaptation in Mediterranean Romulea (Iridaceae) species

Abstract Seed germination is the most important transitional event between early stages in the life cycle of spermatophytes and understanding it is crucial to understand plant adaptation and evolution. However, so far seed germination of phylogenetically closely related species has been poorly investigated. To test the hypothises that phylogenetically related plant species have similar seed ecophysiological traits thereby reflecting certain habitat conditions as a result of local adaptation, we studied seed dormancy and germination in seven Mediterranean species in the genus Romulea (Iridaceae). Both the across‐species model and the model accounting for shared evolutionary history showed that cool temperatures (≤ 15°C) were the main factor that promoted seed germination. The absence of embryo growth before radicle emergence is consistent with a prompt germination response at cool temperatures. The range of temperature conditions for germination became wider after a period of warm stratification, denoting a weak primary dormancy. Altogether these results indicate that the studied species exhibit a Mediterranean germination syndrome, but with species‐specific germination requirements clustered in a way that follows the phylogenetic relatedness among those species. In addition, species with heavier seeds from humid habitats showed a wider range of conditions for germination at dispersal time than species from dry habitats possessing lighter seeds. We conclude that while phylogenetically related species showed very similar germination requirements, there are subtle ecologically meaningful differences, confirming the onset of adaptation to local ecological factors mediated by species relatedness.

Germination requirements of nine European Aegilops species in relation to constant and alternating temperatures

Abstract The genus Aegilops represents the secondary gene pool of wheat. A better understanding of the germination behaviour of Aegilops species is important to improve their use in breeding programmes and strengthen their in situ/ex situ conservation. In this study, we investigated the germination behaviour of nine Aegilops species, five of them not yet investigated, under two alternating and two constant temperatures. Seed germination was higher than 60% in all temperature treatments and species. Alternating temperatures promoted higher germination rates in all the species and significantly enhanced seed germination in three species (Aegilops biuncialis, Aegilops geniculata and Aegilops neglecta), in comparison with constant temperatures. One of the rarest and least productive species in the genus (Aegilops uniaristata) displayed the highest germination. This study suggests that different (seed) regeneration strategies/niches occur across Aegilops species.

A multivariate approach to identify vegetation belts: Gallery forest and its surrounding savanna along the river Kota in north Benin

Abstract The floristic composition and spatial structure of a West African riverine forest in north-western Benin were studied in order to identify vegetation zones and their arrangement and composition. Data were collected on five continuous belt transects and were analysed using multivariate methods. A total of 133 tree taxa from 34 plant families were identified, with Rubiaceae and Leguminosae-Papilionoideae as the most frequent families. Fifteen homogeneous transect sections were documented. Near-river sections were dominated by water-demanding species (Syzygium guineense, Garcinia ovalifolia, Berlinia grandiflora, Breonardia salicina) (=gallery forest), whereas uphill sections were characterised by savanna species (Terminalia laxiflora, Hymenocardia acida, Detarium microcarpum, Burkea africana) (= savanna). The shift from gallery forest to savanna was reflected by a floristic turnover and the different physiognomy of the vegetation, although diversity values for gallery forest and savanna were very similar. In the Principal Co-ordinates Analysis (PCoA), gallery forest and savanna sections did not overlap. Parallel sections at both sides of the river could be linked by isolines following the topography parallel to the river, resulting in a continuous gallery forest belt (width between 10 and 30 m) flanked by savanna. Tree species typical for gallery forests have wider areas of distribution than savanna species.

The Alpine Seed Conservation and Research Network - a new initiative to conserve valuable plant species in the European Alps

Safeguarding plants as seeds in ex situ collections is a cost effective element in an integrated plant conservation approach. The European Alps are a regional centre of plant diversity. Six institutions have established a regional network covering the European Alps which will conserve at least 500 priority plant species and which will improve the conservation status of plant species in grassland communities in the subalpine, alpine and nival altitudinal belts. Targeted research will expand the knowledge of the ecology of target species. Public engagement activities will raise the awareness for the importance of specific conservation actions in the European Alps.

Current availability of seed material of enset (Ensete ventricosum, Musaceae) and its Sub-Saharan wild relatives

Crop wild relatives are an important source of new genetic diversity for plant breeding and crop improvement. Enset (Ensete ventricosum) is mainly cultivated as a multipurpose crop in Ethiopia, supplying food to 13 million people. To improve the agronomic traits of enset clonal lines, sexual propagation can be of key importance, in particular crossbreeding landraces with populations of undomesticated Ensete wild relatives. We investigated the availability of stored seed material of the enset genepool represented by three African Ensete species (E. homblei, E. livingstonianum, E. ventricosum) in gene bank facilities across the world, and also the possibility to obtain freshly collected, undried seed material for conservation and research purposes. We queried the main plant genetic resources databases and contacted 27 gene and seed banks, research centres and several individual researchers. Only one seed bank seemed to hold a seed accession of only one of the three species, E. ventricosum (Millennium Seed Bank of the Royal Botanic Gardens, Kew). Available seed accessions of the other two species (E. homblei, E. livingstonianum) do not seem to exist. The lack of stored seed material of the three Ensete species and the difficulties in obtaining fresh seeds make it impossible to use seeds for breeding and crop improvement. We consider the existing seed conservation measures of the enset crop and its wild relatives as insufficient. A collection, research and ex situ conservation programme targeting Sub-Saharan Ensete seeds is needed considering the potential value of these species for food security across Africa.

Notulae Florae Beninensis - Beckeropsis laxior and Heteranthoecia guineensis (Poaceae) new for Benin (W Africa)

Abstract Müller, J., Sieglstetter, R., Boni, Y. & Scholz, H.: Notulae Florae Beninensis — Beckeropsis laxior and Heteranthoecia guineensis (Poaceae) new for Benin (W Africa). — Willdenowia 32: 237–238.2002. — ISSN 0511-9618. The grass species Beckeropsis laxior and Heteranthoecia guineensis are reported as new to the flora of Benin and are briefly characterised.

Genetic structure of Leucojum aestivum L. in the Po Valley (N-Italy) drives conservation management actions

The aim of this study was to assess the genetic variation and population structure of the geophyte Leucojum aestivum L. across the Po river valley (N-Italy), to inform conservation management actions with the selection of most suitable source populations for translocation purposes. L. aestivum is self-incompatible and occurs in S-Europe in fragmented wetlands and lowland forests along rivers. The species is particularly interesting for habitat restoration practices for its simplicity of ex situ conservation and cultivation. AFLP analyses were carried out on 16 fragmented populations, using four primer combinations. Correlations between genetic variation and demographic and ecological traits were tested. AFLP produced a total of 202 bands, 95.5% of which were polymorphic. Our results suggest that L. aestivum holds low to moderate levels of genetic diversity (mean Nei’s genetic diversity: H = 0.125), mostly within-population. We found a gradient of two main biogeographic groups along western and eastern populations, while the STRUCTURE analysis found that the most likely number of clusters was K = 3, shaping a partially consistent pattern. We explain the unusual negative correlation between genetic variation and population size with the high rate of vegetative reproduction. The levels of population differentiation suggest that fragmentation in L. aestivum populations has occurred, but that an active gene flow between fragmented populations still exists, maintained by flooding events or pollinators. Conservation management actions should improve habitat connectivity, especially for pollinators that vehicle upstream gene flow. Moreover, the west–east structure due to the lithological composition of the gravel and sand forming the alluvial plain of the Po river, should be considered when selecting source populations for translocation purposes.

How to meet the 2020 GSPC target 8 in Europe: priority-setting for seed banking of native threatened plants

The contribution of the European Native Seed Conservation Network (ENSCONET, 2004-2009) and the ENSCONET Consortium (since 2010) towards meeting the 2020 Global Strategy for Plant Conservation (GSPC) target 8 was assessed in 2017. While the outcome was positive (62.7% of European threatened species already conserved ex situ in seed banks), the analysis showed that it was essential to provide guidance on which European native threatened species should be collected as a priority if the target was to be reached by 2020. In this paper we present a priority-setting method and its result, designed to guide collecting strategies across Europe to meet the 2020 GSPC target 8. The result of our study is a country-based checklist of European threatened taxa to be collected and stored ex situ across the seed banks of the ENSCONET Consortium by 2020. After discussing the results of the applied method, the ENSCONET Consortium Steering Committee has identified some key action points to support the implementation of such a collecting strategy across Europe in order to meet the 2020 GSPC target 8 for Europe.