Populus deltoides

Hybrid poplars Populus deltoides x nigra) have attracted considerable interest since they are able to transport and metabolize—even though they do not generally degrade—diverse xenobiotics ... 

Van Aken B, JM Yoon, CL Just, JL Schnoor (2004) Metabolism and mineralization of hexahydro-1,3, 5-trinitro-l,3,5-triazine inside poplar tissues (Populus deltoides x nigra DN-34). Environ Sci Technol 38 4572-4579. 

The use of hybrid poplar (Populus deltoides X P. nigra) has been examined in a few investigations at sites contaminated with creosote. There are several issues that complicate the interpretation of these results, including the physical state of the contaminants, the mechanism of uptake from the soil, and translocation and metabolism in the plants. These have seldom been addressed in studies of PAHs. 

Ro DK, Mah N, EUis BE, Douglas CJ (2001) Functional characterization and subcellular localization of poplar (Populus trichocarpa x Populus deltoides) cinnamate 4-hydroxylase. Plant Physiol 126(1) 317-329... 

Table I. Properties of Populus deltoides Lignin-carbohydrate Complexes...

Figure 1. Scheme used for the purification of Populus deltoides LCCs. 

Figure 2. Representative fractionations employed in the purification of Populus deltoides LCCs. a, initial fractionation of high ("A") and low ("B") molecular weight components through Bio-Gel P-6 b, re-fractionation of "B" through Bio-Gel P-6 c, penultimate fractionation of ARBI on Sephadex G-50 d, penultimate fractionation of Cl components on Sephadex G-50. A280, (O—O) carbohydrate, ( — ).

Table II. Elemental Analysis of Populus deltoides LCC Components ...

Figure 3. FTIR spectra of Populus deltoides LCCs 1,3, and 4, and the ethanol-insoluble fraction used in their preparation.

Table IV. Effect of Enzymes on Populus deltoides LCCs...

Materials. Air dried wood (Populus deltoides) was ground to pass through a screen of 0.5 mm mesh size. These fines were used in the subsequent solvolytic studies. The chemicals used were ethylene glycol (practical grade) sodium hydroxide (practical grade) ethanol (95%) diethyl ether. Calibration-phenols were purchased from Aldrich Chemicals Limited and Alfa Chemicals Limited. 

Study the beavers responses to juvenile vs. adult growth forms. Species used will depend on availability. Best are aspen (Populus tremuloides or P. grandidentata) or cottonwood (Populus deltoides). 

Figure 3 Thermogravirnetric curves of pyrolysis of sawdust from both wood species, Aspidosperma australe (AA) and Populus deltoide (PD) weight fraction (w) against temperature (T). Comparison between experimental data (symbols) and model predictions (solid lines).

All possible patterns of wood density variation appear in hardwoods. The middle to high density diffuse-porous hardwoods generally follow a pattern of low basic density near the pith and then an increase, followed by a slower increase or levelling off toward the bark. The low density, diffuse-porous woods, such as Populus, seem to have a somewhat higher density at the pith, although some have a uniform density from pith to bark [while Populus deltoids increases in density from pith to bark (Shukla et al,... 

Shi SQ (2001) Chapter 11 Fibre reinforced polymer (FRP) - wood hybrid composites. In Williamson TE (ed), APA Handbook on Engineered Wood. McGraw-Hill, New York Shukla NK, Rajput SS, Lai M, and Khanduri AK (1994) Studies on the variation of density and strength properties from pith to periphery in Populus deltoides. Journal of Indian Academy of Wood Science, 2(2) 1-6 Siau JF (1984) Transport processes in wood. Springer-Verlag, Berlin... 

Experiments have been carried out on the mineralization of atra-zine under various conditions (Burken and Schnoor 1996). Although in the absence of plants of poplar hybrids (Populus deltoides nigra DN34), root exudate resulted in only a slight stimulation on the mineralization of 14C-labeled atrazine, addition of crushed roots provided a greater positive effect. 

HMX uptake was evaluated from 21-d hydroponic exposures using hybrid poplar trees (Populus deltoids x nigra) at concentrations of 4.70, 2.84, and 1.37 mg L 1 [80], After 21 d, 44.83% of the HMX in solution was sequestered by the trees. No toxic effects were evident at any of the exposures. The authors also calculated a transpirational stream concentration factor of 0.18 0.03 suggesting that HMX was moderately available for uptake by plant roots. Root concentration factors were also calculated at 5.55 1.78 [80], As with other studies, most HMX was... 

---