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The taxonomy of Bambusoideae is in a state of flux and phylogenetic studies are required to help resolve systematic issues. Over 60 taxa, representing all subtribes of Bambuseae and related non-bambusoid grasses were sampled. A combined analysis of five plastid DNA regions, trnL intron, trnL-F intergenic spacer, atpB-rbcL intergenic spacer, rps16 intron, and matK, was used to study the phylogenetic relationships among the bamboos in general and the woody bamboos in particular. Within the BEP clade (Bambusoideae s.s., Ehrhartoideae, Pooideae), Pooideae were resolved as sister to Bambusoideae s.s. Tribe Bambuseae, the woody bamboos, as currently recognized were not monophyletic because Olyreae, the herbaceous bamboos, were sister to tropical Bambuseae. Temperate Bambuseae were sister to the group consisting of tropical Bambuseae and Olyreae. Thus, the temperate Bambuseae would be better treated as their own tribe Arundinarieae than as a subgroup of Bambuseae. Within the tropical Bambuseae, neotropical Bambuseae were sister to the palaeotropical and Austral Bambuseae. In addition, Melocanninae were found to be sister to the remaining palaeotropical and Austral Bambuseae. We discuss phylogenetic and morphological patterns of diversification and interpret them in a biogeographic context.

The risks of gene flow between interfertile native and introduced plant populations are greatest when there is no spatial isolation of pollen clouds and phenological patterns overlap completely. Moreover, invasion probabilities are further increased if introduced populations are capable of producing seeds by selfing. Here we investigated the mating system and patterns of pollen-mediated gene flow among populations of native ash (Fraxinus excelsior) and mixed plantations of non-native ash (F. angustifolia and F. excelsior) as well as hybrid ash (F. excelsior × F. angustifolia) in Ireland. We analysed the flowering phenology of the mother trees and genotyped with six microsatellite loci in progeny arrays from 132 native and plantation trees (1493 seeds) and 444 potential parents. Paternity analyses suggested that plantation and native trees were pollinated by both native and introduced trees. No signs of significant selfing in the introduced trees were observed and no evidence of higher male reproductive success was found for introduced trees compared with native ones either. A small but significant genetic structure was found (φft=0.05) and did not correspond to an isolation-by-distance pattern. However, we observed a significant temporal genetic structure related to the different phenological groups, especially with early and late flowering native trees; each phenological group was pollinated with distinctive pollen sources. Implications of these results are discussed in relation to the conservation and invasiveness of ash and the spread of resistance genes against pathogens such as the fungus Chalara fraxinea that is destroying common ash forests in Europe.

Amplified fragment length polymorphism (AFLP) and inter-simple sequence repeat markers were employed to characterize a genetic resource collection of Miscanthus, a grass under trial in Europe as a biomass crop. The 26 polymorphic markers produced by two ISSR fingerprinting primers were able to discriminate taxa and identify putative clones. AFLP fingerprints were fully reproducible and produced a larger number of markers for the three primer pairs tested, of which 998 were polymorphic (representing 79.3% of all bands). AFLP markers distinguished species, infra-specific taxa (varieties and cultivars) and putatively clonal material. They were also used to assess the inter-relationships of the taxa, to investigate the origin of important hybrid plants and to estimate the overall level of genetic variation in the collection. They were useful for assessing the species status of certain taxa such as M. transmorrisonensis, an endemic from Taiwan that was clearly distinct from M. sinensis; whereas other taxa of disputed species status, such as M. condensatus and M. yakushimanum were not genetically distinct from M. sinensis. The AFLP markers detected a high degree of infra-specific variation and allowed subdivisions of the genetic resource collection to be made, particularly within M. sinensis.

BACKGROUND AND AIMS: Populations of oak (Quercus petraea and Q. robur) were investigated using morphological and molecular (AFLP) analyses to assess species distinction. The study aimed to describe species distinction in Irish oak populations and to situate this in a European context. METHODS: Populations were sampled from across the range of the island of Ireland. Leaf morphological characters were analysed through clustering and ordination methods. Putative neutral molecular markers (AFLPs) were used to analyse the molecular variation. Cluster and ordination analyses were also performed on the AFLP markers in addition to calculations of genetic diversity and F-statisitcs. KEY RESULTS: A notable divergence was uncovered between the morphological and molecular analyses. The morphological analysis clearly differentiated individuals into their respective species, whereas the molecular analysis did not. Twenty species-specific AFLP markers were observed from 123 plants in 24 populations but none of these was species-diagnostic. Principal Coordinate Analysis of the AFLP data revealed a clustering, across the first two axes, of individuals according to population rather than according to species. High F[subscript ST] values calculated from AFLP markers also indicated population differentiation (F[subscript ST] = 0·271). Species differentiation accounted for only 13 % of the variation in diversity compared with population differentiation, which accounted for 27 %. CONCLUSIONS: The results show that neutral molecular variation is partitioned more strongly between populations than between species. Although this could indicate that the populations of Q. petraea and Q. robur studied may not be distinct species at a molecular level, it is proposed that the difficulty in distinguishing the species in Irish oak populations using AFLP markers is due to population differentiation masking species differences. This could result from non-random mating in small, fragmented woodland populations. Hybridization and introgression between the species could also have a significant role.

The manipulation of DNA is routine practice in botanical research and has made a huge impact on plant breeding, biotechnology and biodiversity evaluation. DNA is easy to extract from most plant tissues and can be stored for long periods in DNA banks. Curation methods are well developed for other botanical resources such as herbaria, seed banks and botanic gardens, but procedures for the establishment and maintenance of DNA banks have not been well documented. This paper reviews the curation of DNA banks for the characterisation and utilisation of biodiversity and provides guidelines for DNA bank management. It surveys existing DNA banks and outlines their operation. It includes a review of plant DNA collection, preservation, isolation, storage, database management and exchange procedures. We stress that DNA banks require full integration with existing collections such as botanic gardens, herbaria and seed banks, and information retrieval systems that link such facilities, bioinformatic resources and other DNA banks. They also require efficient and well-regulated sample exchange procedures. Only with appropriate curation will maximum utilisation of DNA collections be achieved.

Two contrasting molecular techniques, namely DNA sequences and amplified fragment length polymorphisms (AFLP) were used to investigate phylogenetic relationships of Phyllostochys, a large, economieally important genus of woody bamboos. DNA sequences of the internal transcribed spacer (lTS) region of nuclear ribosomal DNA (nrDNA) were used in a parsimony analysis. Phyllostachys was well supported as monophyletic with Chimonobambusa as its closest allied genus. The 5S spacer region of nrDNA was investigated but found unsuitable for this purpose. The AFLP analysis showed much higher discriminating power between species and was more useful for phylogenetic reconstruction at this taxonomic level. The combined data were used to review the previous infra-generic classifieations. Section Heteroclada Wang & Ye is strongly supported and can be further divided into sub-groups. A group within section Phylldstachys is strongly supported, but a further group of taxa previously included in this section is difficut to place. The ability of the methods to help separate species such as P. sulphurea and investigate genetic diversity at the infra-specific level was also assessed. h is argued that AFLPs could often be the method of choice for phylogenetic studies of closely related taxa for which DNA sequence data provide insufficient resolution.

The 21 chapters of this book are based on the theme of a Special Conference of the Systematics Association and the Linnean Society of London, held at Trinity College Dublin (TCD), Ireland, in September 2008. During the three-day Climate Change and Systematics conference, there were stimulating presentations, posters and discussions covering a broad range of ecological and systematic research relating to climate change; these influenced the shape and content of this volume. Papers were contributed by a number of conference delegates and by others subsequently invited to broaden the book's scope or address particular theoretical issues.Consideration of the book's theme began when Richard Bateman, the then President of the Systematics Association, invited John Parnell and the School of Natural Sciences, TCD, to host a conference on the topic and to base a Systematics Association volume around its conclusions. The ideas were refined in discussions with Alan Warren, the then Systematics Association Special Volumes series editor. We are grateful to both for their input and encouragement. Two anonymous book proposal reviewers provided valuable content guidance and many anonymous reviewers also helped to improve the chapter contributions. We are particularly grateful for the manuscript preparation input of Sandra Velthuis of Whitebarn Consulting, who has worked long and hard to proofread chapters and standardise their format, to Hugh Brazier, the excellent copy editor, and to the production team at Cambridge University Press, who have been highly supportive and professional.