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Summary: Thailand is situated in the region of high Bambusa biodiversity which extends from southern China to the Indochinese Peninsula. However, our understanding of Bambusa diversity and biogeography in this region remains incomplete, due to the lack of both local expertise and diagnostic characters on specimens, especially reproductive parts, which are relatively rare occurrences in the wild. Ongoing botanical surveys and flora projects in this region have led to the discovery of new Bambusa species in recent years. Here, a new species, B. lituiformis, and the first record from Thailand of B. nghiana, a Vietnamese species, are reported. The new species and record are described and illustrated from complete collections, using both vegetative and reproductive parts. [ABSTRACT FROM AUTHOR]

Bamboo is a non-timber forest product and one of the most important grass plants of industrial and domestic use. It is widely distributed in tropical countries including India, China and Southeast Asian countries with wide genetic diversity. The diversity in the available genotypes becomes an important resource for the selection and improvement of the plants for ecological and commercial use. This study investigates eight commercially and ecologically important bamboo species of six genera (Bambusa, Dendrocalamus, Thyrsostachys, Vietnamosasa, Cephalostachyum and Indocalamus) from India, Thailand and Laos. These were evaluated for genetic differences by molecular makers, chemo-morphological variation and ability of silicon accumulation. The genetic cluster analyses of eight RAPD primers revealed genetic similarities in the ranges of 24–55%. The total silica content varied from 18.34 to 40.08 ppm in leaves of different bamboo species. Chemical analysis of the silicon content by ICP-OES and secondary metabolite profiling on TLC depicted the prominent distinction among the species. The PCA analysis of quantitative morphological data grouped the species in two major clusters and found to correlate with chemical pattern and genetic similarity to some extent. This is the first report that summarizes species-specific variability of leaf silica content, secondary metabolites, and quantitative morphological data towards delineation of genetic phylogeny of bamboo species. [ABSTRACT FROM AUTHOR]

In this study, we aimed to clarify the forest structure and species composition of a coastal sand dune and the relationship between topographical factors and woody plant distribution at the Bang Boet coastal sand dune, Southern Thailand. Three permanent transect plots (10 × 100 m) covering both windward and leeward aspects were established 300 m apart. In subplots (10 × 10 m) of each transect, all woody plants with a diameter at breast height larger than 1 cm were tagged, measured, and identified. The topographic factors were recorded for each subplot. Non-multidimensional scaling was employed to analyse the woody plant distribution, which was tested for statistical significance. We identified 36 species from 32 genera and 23 families. Species diversity was moderate based on the Shannon–Wiener index (2.81). The density and basal area of all woody plants was 3110 ± 361 stem·ha−1 and 7.34 ± 0.87 m2·ha−1, respectively. The dominant trees species based on the importance value index were Pandanus odorifer, Syzygium antisepticum and Syzygium grande. The forest structure could be classified into two canopy layers, with an open and closed crown canopy on the windward and leeward aspects, respectively. Overall, the distribution of woody plants was significantly correlated with aspect. Species diversity, tree abundance, and basal area differed significantly between the windward and leeward aspects and quantitative values were low on the windward aspect. Due to strong winds and salt spray on the windward side, the woody plant community and distribution favoured the leeward side. [ABSTRACT FROM AUTHOR]

Human impacts have seriously damaged mangroves, and conservation of mangroves will require information on local and regional population genetic structures. Here, we report the development and polymorphism of eleven novel microsatellite markers, developed using next-generation sequencing on 56 samples of widespread mangrove species Xylocarpus granatum (Meliaceae) from nine populations across the Indo-West Pacific region. All loci were found to be polymorphic, with the number of alleles per locus ranging from four to 19. In a population from Sabah (Malaysia), the mean observed and expected heterozygosity per locus was 0.59 and 0.58, respectively. No null allele, significant linkage disequilibrium or deviation from Hardy-Weinberg equilibrium was detected among all loci. The eleven markers developed can be valuable tools to conservation genetics of this species across its distributional range. [ABSTRACT FROM AUTHOR]

A set of 14 new microsatellite markers was developed for mangrove species Rhizophora mucronata (Rhizophoraceae) by using pyrosequencing. Fifty-six samples from 9 populations of R. mucronata in the Indo-West Pacific region were genotyped; all loci were polymorphic, with the number of alleles ranging from 2 to 9. The mean expected heterozygosity per locus was 0.16 in a population from Sabah, no significant linkage disequilibrium was found among loci, and significant deviation from Hardy-Weinberg equilibrium was found in 3 loci. The polymorphic microsatellite markers with samples covering most of the species' distribution range can be applied in genetic diversity studies covering a broad geographical range of the species. [ABSTRACT FROM AUTHOR]

A set of 15 new microsatellite loci was developed and characterized for the widespread mangrove tree species Sonneratia alba (Lythraceae) by using next-generation sequencing. Forty-eight S. alba samples from seven populations in the Indo-West Pacific region were genotyped; all loci were polymorphic, with the number of alleles ranging from three to eight. The mean observed heterozygosity per locus was 0.21 for a population from Sabah, Malaysia. No null allele or significant linkage disequilibrium was detected, indicating the robustness of the markers. Only one locus (SA103) showed deviation from Hardy-Weinberg equilibrium. As characterization of these microsatellite loci was done with samples covering most of the species' distribution range, the markers can be applied to genetic diversity studies over the broad geographical range of the species. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A new monotypic bamboo genus Phuphanochloa ( Poaceae: Bambusoideae) from north-eastern Thailand is described, together with a new species, P. speciosa. [ABSTRACT FROM AUTHOR]