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In line with environmental issues and forest sustainability, tree bark of two species from tropical rain forests i.e. benuang (Octomeles sumatrana/BN) and duabanga (Duabanga moluccana/DB) was used as filler for phenol formaldehyde resin (PF-filler). The main objective of the research was to analyze effect of tree barks as PF-filler on bonding strength of BN and DB glulams produced. Four glue mixture compositions with ratio PF, technical filler, and tree bark filler, respectively are 10: 0: 0 (A); 10: 1.5: 0.5 (B); 10: 1.25: 0.75 (C); and 10: 1: 1 (D) were prepared. Characteristics of tree bark and glue mixtures were also investigated. Glulam parameters i.e. moisture content, density, delamination, bonding strength, wood failure, and formaldehyde emission were determined following JAS 1152. Results showed bonding strength was influenced by wood species and glue mixture composition. The B composition—the lowest ratio of tree bark filler—is the best for BN glulam, while for DB glulam D composition—the highest ratio of tree bark filler—was the best. Generally, tree bark filler improved the bonding strength, however, without bark as PF-filler, the failure occurred on the glue line. Furthermore, DB bark is more potential to be utilized as PF-filler. [ABSTRACT FROM AUTHOR]

The family limits of the Lythraceae and relationships among the ca. 31 genera remain poorly known in spite of previous phylogenetic studies. We use morphology and DNA sequences from the rbcL gene, the trnL-F region, and psaA-ycf3 intergenic spacer of the chloroplast and the internal transcribed spacer region of the nucleus to explore relationships for up to 27 genera of the Lythraceae sensu stricto and the monogeneric families Duabangaceae, Punicaceae, Sonneratiaceae, and Trapaceae. Maximum parsimony, maximum likelihood, and Bayesian likelihood approaches are employed. Morphology alone provided little phylogenetic resolution. Results from individual gene regions were relatively well resolved and largely congruent, whereas basal relationships were poorly supported. A combined gene analysis of 20 genera produced one fully resolved maximum parsimony tree that corresponded closely to the maximum likelihood and Bayesian trees in which a monophyletic Lythraceae includes Duabanga, Punica, Sonneratia, and Trapa as derived genera within the family. Decodon is sister to the rest of the family in the maximum parsimony and Bayesian trees, followed by Lythrum and Peplis at the node above and then by the rest of the family, which diverges into two superclades. In the maximum likelihood tree, the family diverges at the base into two superclades. Six crown clades are well supported but lack unique morphological synapomorphies. Neither superclades nor crown clades correspond to the present tribal and subtribal classification. The New World genera are embedded in four Old World clades. If the basal and near-basal positions for the Northern Hemisphere genera Decodon, Lythrum, and Pep us are confirmed, the origin of the family is more likely Laurasian than Gondwanan. The biogeography and early fossil record of the family indicate that the family originated by the late Cretaceous and had extensively diversified and radiated into Southeast Asia and North America by the lower Eocene. [ABSTRACT FROM AUTHOR]

A permineralized lythraceous leaf type found in close association with fruits, stems, and roots of Decodon allenbyensis Cevallos Ferriz et Stockey in the Middle Eocene Princeton chert of British Columbia, Canada, is described. Midribs have a prominent C-shaped midvein surrounded by sclerenchyma, with an adaxial epidermis of rectangular to rounded cells lacking enlarged mucilage cells. Leaves are dorsiventral, 180-270 µm thick at the lamina, with a double palisade layer. Abaxial epidermal cells have prominent papillae, and these epidermal cells can be infected by fungi, forming dark sterile stromata. Fossil leaves are similar to those of Myrtales and are compared to those of Lythraceae sensu lato. Although these leaves are thought to belong to the previously described Decodon allenbyensis found in the same chert layer, they lack the diagnostic features of extant Decodon leaves. Instead they share most anatomical similarities with Duabanga grandiflora Roxburgh ex DC Walpers (Lythraceae, subfamily Duabangoideae) including vascular tissues, palisade and spongy mesophyll, bundle fibers, and abaxial epidermal papillae. Duabanga grandiflora differs from the fossil in having mucilaginous cells and a consistently V-shaped abaxial midrib. Although anatomically similar to Duabanga, the fossil leaves are considered those of D. allenbyensis, based on association and the depositional environment prior to preservation. Recent phylogenetic analyses place Duabanga and Decodon in separate clades within Lythraceae, but relationships between these clades are not well supported, indicating that fossil leaves should provide useful anatomical characters for elucidating relationships within Lythraceae. [ABSTRACT FROM AUTHOR]