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When plants establish outside their native range, their ability to adapt to the new environment is influenced by both demography and dispersal. However, the relative importance of these two factors is poorly understood. To quantify the influence of demography and dispersal on patterns of genetic diversity underlying adaptation, we used data from a globally distributed demographic research network comprising 35 native and 18 nonnative populations of Plantago lanceolata Species-specific simulation experiments showed that dispersal would dilute demographic influences on genetic diversity at local scales. Populations in the native European range had strong spatial genetic structure associated with geographic distance and precipitation seasonality. In contrast, nonnative populations had weaker spatial genetic structure that was not associated with environmental gradients but with higher within-population genetic diversity. Our findings show that dispersal caused by repeated, long-distance, human-mediated introductions has allowed invasive plant populations to overcome environmental constraints on genetic diversity, even without strong demographic changes. The impact of invasive plants may, therefore, increase with repeated introductions, highlighting the need to constrain future introductions of species even if they already exist in an area.

Figure S1. Predictive ability and bias for crown rust using various algorithms for genomic prediction. (PDF 101 kb)

Figure S2. Among-and-within-full-sib-family selection that incorporates an inexpensive genotyping assay to implement within-family selection using a high selection intensity. (PDF 227 kb)

The conservation of crop genetic resources requires understanding the different variables-cultural, social, and economic-that impinge on crop diversity. In small-scale farming systems, seed exchanges represent a key mechanism in the dynamics of crop genetic diversity, and analyzing the rules that structure social networks of seed exchange between farmer communities can help decipher patterns of crop genetic diversity. Using a combination of ethnobotanical and molecular genetic approaches, we investigated the relationships between regional patterns of manioc genetic diversity in Gabon and local networks of seed exchange. Spatially explicit Bayesian clustering methods showed that geographical discontinuities of manioc genetic diversity mirror major ethnolinguistic boundaries, with a southern matrilineal domain characterized by high levels of varietal diversity and a northern patrilineal domain characterized by low varietal diversity. Borrowing concepts from anthropology-kinship, bridewealth, and filiation-we analyzed the relationships between marriage exchanges and seed exchange networks in patrilineal and matrilineal societies. We demonstrate that, by defining marriage prohibitions, kinship systems structure social networks of exchange between farmer communities and influence the movement of seeds in metapopulations, shaping crop diversity at local and regional levels. The conservation of crop genetic resources requires understanding the different variables-cultural, social, and economic-that impinge on crop diversity. In small-scale farming systems, seed exchanges represent a key mechanism in the dynamics of crop genetic diversity, and analyzing the rules that structure social networks of seed exchange between farmer communities can help decipher patterns of crop genetic diversity. Using a combination of ethnobotanical and molecular genetic approaches, we investigated the relationships between regional patterns of manioc genetic diversity in Gabon and local networks of seed exchange. Spatially explicit Bayesian clustering methods showed that geographical discontinuities of manioc genetic diversity mirror major ethnolinguistic boundaries, with a southern matrilineal domain characterized by high levels of varietal diversity and a northern patrilineal domain characterized by low varietal diversity. Borrowing concepts from anthropology-kinship, bridewealth, and filiation-we analyzed the relationships between marriage exchanges and seed exchange networks in patrilineal and matrilineal societies. We demonstrate that, by defining marriage prohibitions, kinship systems structure social networks of exchange between farmer communities and influence the movement of seeds in metapopulations, shaping crop diversity at local and regional levels. Teagasc IRCSET

Key to Thai species of Dimeria 1. Racemes solitary................................................................................................................................................................................2. - Racemes more than one.....................................................................................................................................................................4. 2. Spikelets 4.5–5 mm long. Rhachis 0.8–1.2 mm wide....................................................................................... D. kurumthotticalana - Spikelets 3–4 mm long. Rhachis 0.4–0.7 mm wide..........................................................................................................................3. 3. Upper glumes wingless........................................................................................................................................................... D. kurzii - Upper glumes winged......................................................................................................................................................... D. sinensis 4. Racemes with filiform rhachis............................................................................................................................................ D. velutina - Racemes with flattened or triangular rhachis....................................................................................................................................5. 5. Spikelets 1–3(–4.5) mm long; upper glumes wingless. Rhachis 0.2–0.4 mm wide.................................................... D. ornithopoda - Spikelets 4–6 mm long; upper glumes winged. Rhachis 0.6–1.2 mm wide......................................................................................6. 6. Upper glumes broadly winged. Wings rugose........................................................................................................................ D. kerrii - Upper glumes narrowly winged. Wings not rugose..........................................................................................................................7. 7. Rhachis 0.7–0.8 mm wide, rhachis internodes 1.5–2(–2.5) mm long. Upper glumes acute, narrowly winged all along the keel.............................................................................................................................................................................................. D. fuscescens - Rhachis 0.8 − 1.2 mm wide, rhachis internodes 0.8–1.5 mm long. Upper glumes acuminate to long acuminate and slightly recurved, narrowly winged in the upper one third of glume to the apex........................................................................... D. kurumthotticalana, Published as part of Teerawatananon, Atchara, Boontia, Veeraya, Chantarasuwan, Bhanumas, Hodkinson, Trevor R. & Sungkaew, Sarawood, 2014, A taxonomic revision of the genus Dimeria (Poaceae: Panicoideae) in Thailand, pp. 137-147 in Phytotaxa 186 (3) on page 138, DOI: 10.11646/phytotaxa.186.3.2, http://zenodo.org/record/5147015

• Premise of the study: We developed nuclear simple sequence repeat (SSR) markers for the characterization of the biomass crop Miscanthus, especially M. sacchariflorus, M. sinensis, and M. ×giganteus, and tested for cross-species amplification. • Methods and Results: Twenty-nine SSR markers (di- and tetranucleotide repeats) were developed from DNA sequences obtained from 192 clones from an enriched genomic library of M. sinensis. All markers were successfully amplified in M. sacchariflorus, M. sinensis, and M. ×giganteus, and 19 amplified across a broad range of Miscanthus species. Polymorphism information content and expected heterozygosity values (19 locus sample) were 0.88 and 0.89, respectively, for M. sinensis, 0.48 and 0.54 for M. sacchariflorus, and were the lowest in M. ×giganteus (0.33, 0.41). Thirteen out of 19 primer pairs showed cross-species amplification in non-Miscanthus sensu stricto taxa. • Conclusions: The new set of 29 SSR markers will be of high value for characterizing Miscanthus germplasm collections, for prebreeding, and for assessing variation in natural populations.

International audience; With 14 species, Badula (Primulaceae) is the most species-rich endemic angiosperm genus of the Mascarene Archipelago. The relationship between Badula and its ally Oncostemum (c. 100 spp; Madagascar and the Comoros Islands) is uncertain, with implications for the circumscription of Badula as a Mascarene endemic. Within Badula, species rarity (several being critically endangered) and a paucity of herbarium specimens hamper proper species delimitations. Here, we estimate the phylogenetic relationships of Badula based on DNA sequence data from the nuclear ribosomal internal transcribed spacer (ITS) and plastid trnS-trnG-trnG regions with complete taxon sampling of the genus and three samples or more of each taxon. The results strongly supported the monophyly of Badula. Paraphyly of Oncostemum was inferred with weak support; explicit hypothesis testing did not favour this hypothesis over one that forced the monophyly of Oncostemum. Monophyly of several Badula spp. was supported, particularly for taxa from the older islands of Mauritius and Rodrigues. Badula is inferred to have reached the Mascarene Archipelago through a single colonization event. The majority of species segregated into island clades, implying that few, rather than multiple, colonization events have occurred in Badula among the islands of the archipelago. (C) 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169, 284296.

End of Project Report This project aimed to develop a better understanding of the potential risks of gene flow and to generate isolation distances required for genetically modified (GM) OSR. The study examined biotic (insect) and abiotic (wind) pollen dispersal over two seasons. A considerable portion of work was devoted to the development of molecular markers, to differentiate Brassica napus varieties from each other to distinguish them from their wild relatives. The project broadly aimed to study gene flow, via pollen movement, from OSR but specifically aimed to: ! Characterise B. napus cv. Marinka using molecular markers. ! Elucidate the distance travelled by OSR pollen by biotic dispersal. ! Elucidate the distance travelled by OSR pollen by abiotic dispersal. ! Elucidate pollination/seed set at various distances from a source crop using male sterile bait plants. ! Develop risk assessment/containment strategies.

We demonstrate that invasive populations of Rhododendron ponticum in Ireland are genetically distinct from ancestral populations in Spain and produce flowers which have wider floral tubes. Although Irish populations are spreading and Spanish ones are declining, we found low genetic diversity among individual plants within populations in both regions, and limited between-population gene flow. Wider floral tubes may have evolved in response to novel pollinators in Ireland. Few studies examine invasive species in both their introduced and native habitats, but this approach is needed to understand invasive species evolution and ecology., Populations of introduced species in their new environments are expected to differ from native populations, due to processes such as genetic drift, founder effects and local adaptation, which can often result in rapid phenotypic change. Such processes can also lead to changes in the genetic structure of these populations. This study investigated the populations of Rhododendron ponticum in its introduced range in Ireland, where it is severely invasive, to determine both genetic and flower width diversity and differentiation. We compared six introduced Irish populations with two populations from R. ponticum's native range in Spain, using amplified fragment length polymorphism and simple sequence repeat genetic markers. We measured flower width, a trait that may affect pollinator visitation, from four Irish and four Spanish populations by measuring both the width at the corolla tip and tube base (nectar holder width). With both genetic markers, populations were differentiated between Ireland and Spain and from each other in both countries. However, populations displayed low genetic diversity (mean Nei's genetic diversity = 0.22), with the largest proportion (76–93 %) of genetic variation contained within, rather than between, populations. Although corolla width was highly variable between individuals within populations, tube width was significantly wider (>0.5 mm) in introduced, compared with native, populations. Our results show that the same species can have genetically distinct populations in both invasive and native regions, and that differences in floral width may occur, possibly in response to ecological sorting processes or local adaptation to pollinator communities.