Lignocellulose, composed of cellulose, hemicellulose, and lignin, in the secondary cell wall constitutes wood and is the most abundant form of biomass on Earth. Enhancement of wood accumulation may be an effective strategy to increase biomass as well as wood strength, but currently only limited research has been undertaken. Here, we demonstrated that OsSWN1, the orthologue of the rice NAC Secon...

Poplar has emerged as a model plant for better understanding cellular and molecular changes accompanying tree growth, development, and response to environment. Long-term application of different forms of nitrogen (such as [Formula: see text]-N and [Formula: see text]-N) may cause morphological changes of poplar roots; however, the molecular level changes are still not well-known. In this study,...

Two polyphenol oxidase isoforms with distinct expression patterns were identified in hybrid poplar (Populus trichocarpaxP. deltoides). PPO-1, corresponding to the previously cloned PtdPPO (Constabel et al., Plant Physiol. 124: 285-295) was primarily leaf tissue-specific and detected only after wounding. PPO-2 was expressed constitutively in all tissue types tested except mature leaves, with hig...

• In an effort to understand processes that are related to heavy metal sequestration, we characterized six metallothionein genes ( PtdMTs ) in the hybrid cottonwood, Populus trichocarpa × deltoides . • cDNA microarrays and reverse transcriptase-polymerase chain reaction were used to examine PtdMT expression in poplar tissues. They displayed differential gene expression patterns, which may be as...

The Poplar copper-molybdenum porphyry deposit, 50 kilometres south-southwest of Houston, is centred near 54 degrees 01 minute north and 126 degrees 50 minutes west. The property is accessible from Houston via 80 kilometres of forest access roads along the Morice River, Owen Lake, Tahtsa Reach, and Poplar Lake. The deposit is situated on the northeast shore of Tagetochlain (Poplar) Lake in an ar...

Lignin is an integral cell wall component of all vascular plants. Peroxidases are widely believed to catalyze the last enzymatic step in the biosynthesis of lignin, the dehydrogenation of the p-coumaryl alcohols. As the first stage in identifying lignin-specific peroxidase isoenzymes, the classical anionic peroxidases found in the xylem of poplar (Populus trichocarpa Trichobel) were purified an...

The safety of timber structure design based on the predicted Modulus of Rupture (MOR) of poplar lumber with nondestructive methods is presented in this paper. Dynamic Modulus of Elasticity (MOE) of poplar lumber was measured with three different nondestructive methods, and static MOE and MOR were obtained by a static bending test. The regression relationship between various MOE and MOR was eval...

Critical cellulase and hemicellulase activities are identified for hydrolysis of ionic liquid (IL) pretreated poplar and switchgrass; hemicellulase rich substrates with largely amorphous cellulose. Enzymes from Aspergillus nidulans were expressed and purified: an endoglucanase (EG) a cellobiohydrolase (CBH), an endoxylanase (EX) and an acetylxylan esterase (AXE). β-Xylosidase (βX) from Selenomo...

Current West Virginia coal mining regulations emphasize reforestation as a preferred postmining land use on surface mined areas. Some mined sites reclaimed to pasture are being converted to forests. In the spring of 2001, we compared the establishment and growth of five hardwood tree species on a reclaimed West Virginaia surface mine with compacted soils and a heavy grass groundcover. We plante...

A wild-type poplar hybrid and two transgenic clones overexpressing a bacterial gamma-glutamylcysteine synthetase in the cytosol or in the chloroplasts were exposed to the chloroacetanilide herbicides acetochlor and metolachlor dispersed in the soil. The transformed poplars contained higher gamma-glutamylcysteine and glutathione (GSH) levels than wild-type plants and therefore it was supposed th...