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Sample records for hybrid poplar growth

  1. Variation in the Growth Traits and Wood Properties of Hybrid White Poplar Clones

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    Huandi Ma

    2015-04-01

    Full Text Available The physical and chemical properties of poplar clones largely determine their suitability for different applications. The main objective of this study was to investigate clonal variation in four hybrid poplar clones grown at three sites in North China and identify the superior clone. Study materials were collected from four clones of hybrid white poplar: Populus tomentosa “LM50”, used as the control; two clones (Yiyang-1 and Yiyang-2, new hybrids of (P. tomentosa × P. bolleana × P. tomentosa “Truncata”; and Yiyang-3, a new hybrid of (P. tomentosa × P. bolleana × P. tomentosa “LM50”. In total, 192 individuals from four hybrid clones were randomly chosen for sampling. The growth traits of four 7-year-old clones were examined at three sites. We also measured the wood properties of four 6-year-old clones at the Fengfeng nursery. Variation in the growth traits and the ranking of stem volumes differed among sites. Fiber traits and wood chemical components showed significant interclonal variation. With regard to the comprehensive growth rate, cellulose content, holocellulose content, and fiber traits, Yiyang-1 exhibited the best performance among the four hybrid poplar clones, indicating its utility as a raw material for pulp and papermaking.

  2. Comparing growth and fine root distribution in monocultures and mixed plantations of hybrid poplar and spruce

    Institute of Scientific and Technical Information of China (English)

    Lahcen Benomar; Annie DesRochers; Guy R.Larocque

    2013-01-01

    Disease prevention,biodiversity,productivity improvement and ecological considerations are all factors that contribute to increasing interest in mixed plantations.The objective of this study was to evaluate early growth and productivity of two hybrid poplar clones,P.balsamifera x trichocarpa (PBT) and P.maximowiczii x balsamifera (PMB),one improved family of Norway spruce (Picea glauca (PA)) and one improved family of white spruce (Picea abies (PG)) growing under different spacings in monocultures and mixed plots.The plantations were established in 2003 in Abitibi-Témiscamingue,Quebec,Canada,in a split plot design with spacing as the whole plot factor (1 × 1 m,3 × 3 m and 5 × 5 m) and mixture treatments as subplot factor (pure:PBT,PMB,PA and PG,and 1:1 mixture PBT:PA,PBT:PG,PMB:PA and PMB:PG).Results showed a beneficial effect of the hybrid poplar-spruce mixture on diameter growth for hybrid poplar clones,but not for the 5 × 5 m spacing because of the relatively young age of the plantations.Diameter growth of the spruces decreased in mixed plantings in the 1 × 1 m,while their height growth increased,resulting in similar aboveground biomass per tree across treatments.Because of the large size differences between spruces and poplars,aboveground biomass in the mixed plantings was generally less than that in pure poplar plots.Leaf nitrogen concentration for the two spruce families and hybrid poplar clone PMB was greater in mixed plots than in monocultures,while leaf nitrogen concentration of clone PBT was similar among mixture treatments.Because of its faster growth rate and greater soil resources demands,clone PMB was the only one showing an increase in leaf N with increased spacing between trees.Fine roots density was greater for both hybrid poplars than spruces.The vertical distribution of fine roots was insensitive to mixture treatment.

  3. Influence of Climate on the Growth of Hybrid Poplar in Michigan

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    Sophan Chhin

    2010-11-01

    Full Text Available This study examined the influence of climate on cumulative and interannual growth patterns of 18 full-sib families of hybrid poplars (Populus × smithii Boivin derived from different geographical locations (state counties of natural stands of aspen parents (trembling aspen (Populus tremuloides Michx. and bigtooth aspen (Populus grandidentata Michx.. The hybrids were subsequently planted in 1982 in southern mid-Michigan at Michigan State University (MSU Sandhill Research Area. Cumulative measures of hybrid poplar productivity (diameter, height, basal area, and stem volume in 2009 (28 years since plantation establishment were related via correlation analysis to geographical distances and climatic variables (temperature and precipitation between parental county locations and between parental locations and the plantation site. Tree-ring analysis methods (dendrochronology were also used to quantify the influence of climate (i.e., mean temperature and total precipitation at monthly and 3-month seasonal scales on interannual basal area growth rates of hybrid poplars. Analyses of cumulative measures of growth indicated a maternal effect: full-sib families had higher productivity if they had a maternal parent originating from a state county that was close to or had higher temperature (annual and summer and summer precipitation than corresponding parameters of the planting site. Principal component analysis indicated that 17 of the 18 full-sib families shared a large amount of common growth variation. Dendrochronological analyses of interannual growth-climate relationships indicated that growth was mainly affected by the degree of late summer to fall moisture stress in both the current and previous growth season, and the degree of winter harshness.

  4. Effects of apical meristem loss on sylleptic branching and growth of hybrid poplar

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    Zeleznik, Joseph D. [North Dakota State University, Fargo, ND (United States). Plant Sciences Department

    2007-07-15

    The effects of apical meristem loss on the growth and development of hybrid poplar trees was investigated. This was done by clipping back either the apical meristem alone (dividing cells), or the apical meristem plus a small amount of additional stem tissue (expanding cells, <1 cm), at various times during the first growing season. Two clones (NM6-nonsylleptic habit, and DN34-slightly sylleptic habit) were tested at close spacing (0.6 m) in the nursery. Clipping generally increased the number of sylleptic branches formed. Clipping 69 days after planting resulted in the largest number of sylleptic branches while clipping 4 weeks later gave no increase in syllepsis. Clipping temporarily reduced height growth of both clones but total height at the end of the first growing season was not affected by any treatment. There were some slight differences in growth during the second growing season; despite these differences, total stem biomass and total tree biomass after 2 years were not affected by temporary loss of the apical meristem in the first growing season. Results suggest that death or removal of hybrid poplar apical meristems by tip borers or ungulates has no long-term effects on aboveground growth as measured by height or biomass. (author)

  5. Use of Sulfometuron in Hybrid Poplar Energy Plantations

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    Daniel A. Netzer

    1995-01-01

    Reports that low rates of sulfometuron, 70 grams per hactare (1 ounce product or 0.75 ounces active ingredient per acre), applied when hybrid poplars are completely dormant, can provide season-long weed control and increase hybrid poplar growth. If plantation access is not possible before growth activity begins in the spring, late fall application of this herbicide...

  6. Reduced expression of the SHORT-ROOT gene increases the rates of growth and development in hybrid poplar and Arabidopsis.

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    Jiehua Wang

    Full Text Available SHORT-ROOT (SHR is a well characterized regulator of cell division and cell fate determination in the Arabidopsis primary root. However, much less is known about the functions of SHR in the aerial parts of the plant. In this work, we cloned SHR gene from Populus trichocarpa (PtSHR1 as an AtSHR ortholog and down-regulated its expression in hybrid poplar (Populus tremula×P. tremuloides Michx-clone T89 in order to determine its physiological functions in shoot development. Sharing a 90% similarity to AtSHR at amino acid level, PtSHR1 was able to complement the Arabidopsis shr mutant. Down regulation of PtSHR1 led to a strong enhancement of primary (height and secondary (girth growth rates in the transgenic poplars. A similar approach in Arabidopsis showed a comparable accelerated growth and development phenotype. Our results suggest that the response to SHR could be dose-dependent and that a partial down-regulation of SHR could lead to enhanced meristem activity and a coordinated acceleration of plant growth in woody species. Therefore, SHR functions in plant growth and development as a regulator of cell division and meristem activity not only in the roots but also in the shoots. Reducing SHR expression in transgenic poplar was shown to lead to significant increases in primary and secondary growth rates. Given the current interest in bioenergy crops, SHR has a broader role as a key regulator of whole plant growth and development and SHR suppression has considerable potential for accelerating biomass accumulation in a variety of species.

  7. Tree-based intercropping systems increase growth and nutrient status of hybrid poplar: a case study from two Northeastern American experiments.

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    Rivest, David; Cogliastro, Alain; Olivier, Alain

    2009-01-01

    Tree-based intercropping is considered to be a potentially useful land use system for mitigating negative environmental impacts from intensive agriculture such as nutrient leaching and greenhouse gas emissions. Rapid early growth of trees is critical for rapidly accruing environmental benefits provided by the trees. We tested the hypothesis that intercropping increases the growth and nutrient status of young hybrid poplars (Populus spp.), compared to a harrowing alley treatment (i.e., no intercrop), in two experimental sites (St-Rémi and St-Edouard) in southern Québec, Canada. Three hybrid poplar clones (TD3230, Populus trichocarpa x deltoides; DN3308, P. deltoides x nigra; and NM3729, P. nigra x maximowiczii) were planted at St-Rémi. Clones DN3333 and DN3570 were planted at St-Edouard. At St-Rémi, intercropping comprised a 4-year succession of three crops of soybean (Glycine max (L.) Merr.) and barley (Hordeum vulgare L.). At St-Edouard, intercropping comprised a 3-year succession of buckwheat (Fagopyrum esculentum Moench), winter rye (Secale cereale L.), and winter wheat (Triticum aestivum L.). At St-Rémi, four years after treatment began, leafless aboveground biomass of hybrid poplars in the intercropping treatment was 37% higher compared to that in the harrowing treatment. At St-Edouard, after the third growing season, leafless aboveground biomass of hybrid poplars in the intercropping treatment was significantly higher by 40%. Vector analysis of foliar nutrient concentrations and comparison with critical concentration values showed that N (both sites) and K (St-Edouard) were the most limiting nutrients. Hybrid poplar clones responded similarly to treatments, with no consistent differences in tree growth observed between clones. We conclude that tree-based intercropping systems may offer an effective means of improving the early growth of hybrid poplars planted to provide both environmental services and high-value timber.

  8. Influence of brick air scrubber by-product on growth and development of corn and hybrid poplar.

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    Thomas, Carla N; Bauerle, William L; Owino, Tom O; Chastain, John P; Klaine, Stephen J

    2007-03-01

    Studies were conducted to determine the effects of spent reagent from air pollution control scrubbers used at a brick manufacturing facility on emergence, growth, and physiological responses of corn and hybrid poplar plants. Scrubber by-product was obtained from General Shale Brick, Louisville, KY. Potting substrate was weighed and quantities of scrubber by-product were added to the substrate to obtain treatments of 0%, 6.25%, 12.5%, 25%, 50%, 75%, and 100% scrubber by-product (w:w) for the corn study. Each treatment mix was potted into nine replicate polyethylene pots and four corn seeds were sown per pot. The pots were randomized in a greenhouse at Clemson University and the number of seedlings emerging from each treatment, dark-adapted leaf chlorophyll a fluorescence, and shoot heights were measured at the end of a 21-day growth period. Then, dry shoot biomass was determined for plants from each treatment and plant tissues were analyzed for selected constituents. For the poplar study, nine-inch cuttings of hybrid poplar clone 15-29 (Populus trichocarpa x P. deltoides) and clone OP367 (P. deltoides x P. nigra) were planted in treatments of scrubber by-product-potting soil mixes of 0% , 5% , 10% , and 25% w:w. Leaf chlorophyll a fluorescence was measured over six weeks and cumulative leaf area, dry biomass, and nutrient content of tissues were determined upon harvest. Results of these studies indicate that percent seedling emergence for corn plants decreased with increasing scrubber by-product application rates. Application rates up to 12.5% scrubber by-product w:w had no adverse effect on corn seedling emergence. Shoot elongation, biomass production, and the status of the photosynthetic apparatus of the seedlings were also not severely impaired at applications below this level. A critical value of 58.2% w:w scrubber by-product was estimated to cause 25% inhibition of seedling emergence. Biomass production, cumulative leaf area, and chlorophyll a fluorescence of

  9. Green revolution trees: semidwarfism transgenes modify gibberellins, promote root growth, enhance morphological diversity, and reduce competitiveness in hybrid poplar.

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    Elias, Ani A; Busov, Victor B; Kosola, Kevin R; Ma, Cathleen; Etherington, Elizabeth; Shevchenko, Olga; Gandhi, Harish; Pearce, David W; Rood, Stewart B; Strauss, Steven H

    2012-10-01

    Semidwarfism has been used extensively in row crops and horticulture to promote yield, reduce lodging, and improve harvest index, and it might have similar benefits for trees for short-rotation forestry or energy plantations, reclamation, phytoremediation, or other applications. We studied the effects of the dominant semidwarfism transgenes GA Insensitive (GAI) and Repressor of GAI-Like, which affect gibberellin (GA) action, and the GA catabolic gene, GA 2-oxidase, in nursery beds and in 2-year-old high-density stands of hybrid poplar (Populus tremula × Populus alba). Twenty-nine traits were analyzed, including measures of growth, morphology, and physiology. Endogenous GA levels were modified in most transgenic events; GA(20) and GA(8), in particular, had strong inverse associations with tree height. Nearly all measured traits varied significantly among genotypes, and several traits interacted with planting density, including aboveground biomass, root-shoot ratio, root fraction, branch angle, and crown depth. Semidwarfism promoted biomass allocation to roots over shoots and substantially increased rooting efficiency with most genes tested. The increased root proportion and increased leaf chlorophyll levels were associated with changes in leaf carbon isotope discrimination, indicating altered water use efficiency. Semidwarf trees had dramatically reduced growth when in direct competition with wild-type trees, supporting the hypothesis that semidwarfism genes could be effective tools to mitigate the spread of exotic, hybrid, and transgenic plants in wild and feral populations.

  10. Perturbed lignification impacts tree growth in hybrid poplar--a function of sink strength, vascular integrity, and photosynthetic assimilation.

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    Coleman, Heather D; Samuels, A Lacey; Guy, Robert D; Mansfield, Shawn D

    2008-11-01

    The effects of reductions in cell wall lignin content, manifested by RNA interference suppression of coumaroyl 3'-hydroxylase, on plant growth, water transport, gas exchange, and photosynthesis were evaluated in hybrid poplar trees (Populus alba x grandidentata). The growth characteristics of the reduced lignin trees were significantly impaired, resulting in smaller stems and reduced root biomass when compared to wild-type trees, as well as altered leaf morphology and architecture. The severe inhibition of cell wall lignification produced trees with a collapsed xylem phenotype, resulting in compromised vascular integrity, and displayed reduced hydraulic conductivity and a greater susceptibility to wall failure and cavitation. In the reduced lignin trees, photosynthetic carbon assimilation and stomatal conductance were also greatly reduced, however, shoot xylem pressure potential and carbon isotope discrimination were higher and water-use efficiency was lower, inconsistent with water stress. Reductions in assimilation rate could not be ascribed to increased stomatal limitation. Starch and soluble sugars analysis of leaves revealed that photosynthate was accumulating to high levels, suggesting that the trees with substantially reduced cell wall lignin were not carbon limited and that reductions in sink strength were, instead, limiting photosynthesis.

  11. Summer is the best time to thin hybrid poplar plantations

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    Harold F. Ford; Albert G., Jr. Snow

    1954-01-01

    Hybrid poplar plantations are established by planting dormant cuttings in close spacing, usually 4 x 4 feet. They are cultivated during the first growing season to eliminate competition from grasses and weeds. After the first year, the more vigorous trees effectively shade out lower vegetation. But rapid tree growth often makes thinning necessary after 2 or 3 growing...

  12. Growth and carbohydrate status of coppice shoots of hybrid poplar following shoot pruning.

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    Tschaplinski, T J; Blake, T J

    1995-05-01

    Fifteen, 1-year-old Populus maximowiczii Henry x P. nigra L. 'MN9' trees were decapitated and allowed to sprout. After 8 weeks, all had 6 to 10 coppice shoots. All shoots, except the tallest (dominant) shoot, were removed from five of the trees (pruned treatment), and shoot growth, gas exchange and carbohydrate status were compared in the pruned and unpruned trees. Although photosynthetic rate of recently mature leaves of pruned trees was approximately 50% greater than that of leaves on the dominant shoot of unpruned trees, and the dry weight of leaves of pruned trees was 37% greater than that of the leaves on the dominant shoot of unpruned trees, the shoot dry matter relative growth rate did not differ between treatments. Concentrations of water-soluble carbohydrates and starch in the uppper stem and leaves of the dominant shoot were similar in pruned and unpruned trees. However, relative to that of the dominant shoot in unpruned trees, the lower stem in pruned trees was depleted in both soluble carbohydrates and starch. Starch deposition, assessed as the quantity of (14)C-starch in tissues 24 h after a fully expanded source leaf was labeled with (14)CO(2), was 3.9 times greater in roots of pruned trees than in roots of unpruned trees. We conclude that early removal of all but the dominant shoot reduces the carbohydrate status of the roots and the lower portion of the stem by eliminating the excised shoots as a source of photosynthate.

  13. Altering carbon allocation in hybrid poplar (Populus alba × grandidentata) impacts cell wall growth and development.

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    Unda, Faride; Kim, Hoon; Hefer, Charles; Ralph, John; Mansfield, Shawn D

    2016-12-20

    Galactinol synthase is a pivotal enzyme involved in the synthesis of the raffinose family of oligosaccharides (RFOs) that function as transport carbohydrates in the phloem, as storage compounds in sink tissues and as soluble metabolites that combat both abiotic and biotic stress in several plant species. Hybrid poplar (Populus alba × grandidentata) overexpressing the Arabidopsis thaliana GolS3 (AtGolS3) gene showed clear effects on development; the extreme overexpressing lines were stunted and had cell wall traits characteristic of tension wood, whereas lines with only moderate up-regulation grew normally and had moderately altered secondary cell wall composition and ultrastructure. Stem cross-sections of the developing xylem revealed a significant increase in the number of vessels, as well as the clear presence of a G-layer in the fibres. Furthermore, AtGolS3-OE lines possessed higher cellulose and lower lignin contents, an increase in cellulose crystallinity, and significantly altered hemicellulose-derived carbohydrates, notably manifested by their mannose and xylose contents. In addition, the transgenic plants displayed elevated xylem starch content. Transcriptome interrogation of the transgenic plants showed a significant up-regulation of genes involved in the synthesis of myo-inositol, along with genes involved in sucrose degradation. The results suggest that the overexpression of GolS and its product galactinol may serve as a molecular signal that initiates metabolic changes, culminating in a change in cell wall development and potentially the formation of tension wood.

  14. GROWTH AND PRODUCTIVITY OF POPLAR SPECIES IN SOUTHEASTERN KAZAKHSTAN

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    Dani Sarsekova

    2015-09-01

    Full Text Available A small area of forestation and an acute shortage of timber are reasons to seek ways to improve  productivity and the rational use of forests in the territory of Kazakhstan. A deficit in timber can be compensated, to some extent, by planting stands of fast-growing plantation species, including top and hybrid Populus spp, which are commonly referred to as “poplar”.There is an increased interest in poplar, globally, due to its organic traits and the economic value it provides, including:rapid growth and ability to produce wood that is technically suitable for cutting within 20 years of planting;a source of suitable timber for use in most industries;the ability to grow in soils that are not  generally suitable for agricultural use;a potential source of timber for widespread use in screening, landscape and recreational plantings; andthe ability of most poplar species and hybrids to asexually propagate.There has been extensive planting of poplar trees in Kazakhstan, especially in the south and south-east. Poplar trees have been planted in populated areas, along roads and in forest stands. However, these plantings are unsuitable as a source of timber for commercial or ornamental purposes. Hence, there is a need to establish plantations of poplar for timber supply in Kazakhstan.The  most common types of poplar in this country are the deltoid, Algerian, and Bolle, which were used in the extensive greenery planting of southeastern Kazakhstan. The main factors ensuring high productivity of poplar plantations are the soil conditions of fertility, good aeration and adequate moisture. Results of this study indicate that the greatest height increase occurs in these trees between the age of 5 and 10 years, and for trunk diameter, between the age of 4 and 9 years. After this age, the growth rate gradual declines, with a sharp fall off in the rate noticeable between years 14 and 16. Additionally, results of this study show the high productivity of poplar

  15. Analysis of genetic and environmental effects on hybrid poplar rooting in Central and Northern Minnesota, USA

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    Ronald S., Jr. Zalesny; Don Riemenschneider; Edmund Bauer

    2000-01-01

    We studied genetic and environmental effects on adventitious root initiation and growth because rooting is biologically prerequisite to the establishment of hybrid poplar plantations. Six clones from two pedigrees (pure Populus deltoides "cottonwoods" and P. deltoides x P. maximowiczii hybrids) were...

  16. Genetic variation of hydraulic and wood anatomical traits in hybrid poplar and trembling aspen.

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    Schreiber, Stefan G; Hacke, Uwe G; Hamann, Andreas; Thomas, Barb R

    2011-04-01

    Intensive forestry systems and breeding programs often include either native aspen or hybrid poplar clones, and performance and trait evaluations are mostly made within these two groups. Here, we assessed how traits with potential adaptive value varied within and across these two plant groups. Variation in nine hydraulic and wood anatomical traits as well as growth were measured in selected aspen and hybrid poplar genotypes grown at a boreal planting site in Alberta, Canada. Variability in these traits was statistically evaluated based on a blocked experimental design. We found that genotypes of trembling aspen were more resistant to cavitation, exhibited more negative water potentials, and were more water-use-efficient than hybrid poplars. Under the boreal field test conditions, which included major regional droughts, height growth was negatively correlated with branch vessel diameter (Dv ) in both aspen and hybrid poplars and differences in Dv were highly conserved in aspen trees from different provenances. Differences between the hybrid poplars and aspen provenances suggest that these two groups employ different water-use strategies. The data also suggest that vessel diameter may be a key trait in evaluating growth performance in a boreal environment.

  17. Sapflow of hybrid poplar (Populus nigra L. x P. maximowiczii A. Henry 'NM6') during phytoremediation of landfill leachate

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    Ronald S., Jr. Zalesny; Adam H. Wiese; Edmund O. Bauer; Don E. Riemenschneider

    2006-01-01

    Poplars are ideal for phytoremediation because of their high water usage, fast growth, and deep root systems. We measured in 2002 and 2003 the sapflow of hybrid poplars (Populus nigra L. x P. maximowiczii A. Henry 'NM6') planted in 1999 for phytoremediation of a landfill in Rhinelander, WI, USA (45.6?N, 89.4?W).

  18. DIMENSIONAL STABILITY OF METHYL METHACRYLATE HARDENED HYBRID POPLAR WOOD

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    Wei-Dan Ding,

    2011-11-01

    Full Text Available This study examines the dimensional stability of fast-growing poplar clones wood after treatment by impregnation with methyl methacrylate (MMA. Six hybrid poplar clones from one plantation in Quebec were sampled. The effects of hardening with MMA on density as well as longitudinal, radial, tangential, and volumetric swelling properties (S, water uptake capacity (D, anti-swelling efficiency (ASE, and water repellent efficiency (WRE after soaking were investigated. Hardening treatment increased the density of all poplar woods by 1.2 to 1.6 and decreased the inner water migration rate during soaking. S and D values of hardened woods were significantly lower than those of controls, depending on the clone type. ASE and WRE values suggested that incorporating MMA effectively improved the dimensional stability of poplar wood at the early soaking stage, but was less effective in the long term.

  19. Co-pyrolysis of different type coals with hybrid poplar

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    Hanzade Haykiri-Acma; Serdar Yaman [Istanbul Technical University, Istanbul (Turkey). Dept. of Chemical Engineering

    2007-07-01

    The aim of this study is to investigate the co-pyrolysis characteristics of different rank coals such as peat, lignite, and anthracite in the presence of hybrid poplar. For this purpose, non-isothermal thermogravimetry technique was applied up to 900{sup o}C with a heating rate of 40{sup o}C/min under dynamic nitrogen flow of 40 mL/min. Hybrid poplar was added into each coal as much as 10 wt % of the coal sample and the experiments were repeated. Pyrolytic properties such as the char yields, gasification rates, and reactivity of the original samples and the blends were compared from the thermal analysis data, and interpreted. Addition of hybrid poplar to coal had some influences on the pyrolytic properties of coals that might be explained by the synergistic interaction approach. 15 refs., 3 figs., 4 tabs.

  20. Seedling test and genetic analysis of white poplar hybrid clones

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    LI Bo; JIANG Xi-bing; ZHANG You-hui; ZHANG Zhi-yi; LI Shan-wen; AN Xin-min

    2008-01-01

    Cross breeding strategies are very efficient for gaining new and superior genotypes. Ninety-eight new white poplar hybrid clones produced from 12 cross combinations within the Section Leuce Duby were studied using genetic analysis and seedling tests. We exploited the wide variation that exists in this population and found that the differences among diameter at breast height (DBH), root collar diameter (RCD) and height (H) were statistically extremely significant. The repeatability of clones of these measured traits ranged from 0.947-0.967, which indicated that these Waits were strongly controlled by genetic factors. Based on multiple comparisons, a total of 25 clones showed better performance in growth than the conlrol cultivar. These 25 clones were from six different cross combinations, which can guarantee a larger genetic background for future new clone promotion projects. This study provides a simple overview on these clones and can guide us to carry out subsequent selection plans.

  1. Contrasting colonization and plant growth promoting capacity between wild type and gfp-derative of the endophyte Pseudomonas putida W619 in hybrid poplar

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    Weyens N.; van der Lelie D.; Boulet, J.; Adriaensen, D.; Timmermans, J.-P.; Prinsen, E.; Van Oevelen, S.; D" Haen, J.; Smeets, K.; Taghavi, S.; Vangronsveld, J.

    2011-06-09

    This study aims to investigate the colonization of poplar by the endophyte Pseudomonas putida W619 and its capacity to promote plant growth. Poplar cuttings were inoculated with P. putida W619 (wild-type or gfp-labelled). The colonization of both strains was investigated and morphological, physiological and biochemical parameters were analyzed to evaluate plant growth promotion. Inoculation with P. putida W619 (wild-type) resulted in remarkable growth promotion, decreased activities of antioxidative defence related enzymes, and reduced stomatal resistance, all indicative of improved plant health and growth in comparison with the non-inoculated cuttings. In contrast, inoculation with gfp-labelled P. putida W619 did not promote growth; it even had a negative effect on plant health and growth. Furthermore, compared to the wildtype strain, colonization by the gfp-labelled P. putida W619::gfp1 was much lower; it only colonized the rhizosphere and root cortex while the wild-type strain also colonized the root xylem vessels. Despite the strong plant growth promoting capacity of P. putida W619 (wild-type), after gfp labelling its growth promoting characteristics disappeared and its colonization capacity was strongly influenced; for these reasons gfp labelling should be applied with sufficient caution.

  2. Economic investigations of short rotation intensively cultured hybrid poplars

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    David C. Lothner

    1983-01-01

    The history of the economic analyses is summarized for short rotation intensively cultured hybrid poplar at the North Central Forest Experiment Station. Early break-even analyses with limited data indicated that at a price of $25-30 per dry ton for fiber and low to medium production costs, several systems looked profitable. Later cash flow analyses indicated that two...

  3. Aboveground dendromass allometry of hybrid black poplars for energy crops

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    Tatiana Stankova

    2016-06-01

    Full Text Available Cultivation of energy crops is concerned with estimation of the total lignified biomass (dendromass production, which is based on the plantation density and individual plant dendromass. The main objective of this study was to investigate the allometry of aboveground leafless biomass of juvenile black poplar hybrids (Populus deltoides x P. nigra , traditionally used for timber and cellulose production, and to derive generic allometric models for dendromass prediction, relevant to energy crop cultivation in Bulgaria. The study material comprised a variety of growth sites, tree ages and clones, specific to poplar plantings in Bulgaria. We used three principal quantitative predictors: diameter at breast height, total tree height and mean stand (stock height. The models were not differentiated by clone, because the black poplar hybrids tested were not equally represented in the data, and the inclusion of tree age as a predictor variable seemed unreliable, because of the significant, up to 3 years, variation, which was possible within the narrow age range investigated. We defined the mean stand (stock height as a composite quantitative variable, which reflected the interaction between the time since planting (age, site quality and the intrinsic growth potential. Stepwise and backward multiple regression analyses were applied to these quantitative variables and their products and sets of adequacy and goodnessof-fit criteria were used to derive individual biomass models for stem and branches. Then we developed compatible additive systems of models for stem, branch and total lignified biomass in log-transformed form. Finally, the prediction data were back-transformed, applying correction for bias, and were cross-validated. Three systems of generic equations were derived to enable flexible model implementation. Equation system M1 proposes a stem biomass model based on tree and stand heights and stem diameter, and a model for

  4. Aboveground dendromass allometry of hybrid black poplars for energy crops

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    Tatiana Stankova

    2016-06-01

    Full Text Available Cultivation of energy crops is concerned with estimation of the total lignified biomass (dendromass production, which is based on the plantation density and individual plant dendromass. The main objective of this study was to investigate the allometry of aboveground leafless biomass of juvenile black poplar hybrids (Populus deltoides x P. nigra , traditionally used for timber and cellulose production, and to derive generic allometric models for dendromass prediction, relevant to energy crop cultivation in Bulgaria. The study material comprised a variety of growth sites, tree ages and clones, specific to poplar plantings in Bulgaria. We used three principal quantitative predictors: diameter at breast height, total tree height and mean stand (stock height. The models were not differentiated by clone, because the black poplar hybrids tested were not equally represented in the data, and the inclusion of tree age as a predictor variable seemed unreliable, because of the significant, up to 3 years, variation, which was possible within the narrow age range investigated. We defined the mean stand (stock height as a composite quantitative variable, which reflected the interaction between the time since planting (age, site quality and the intrinsic growth potential. Stepwise and backward multiple regression analyses were applied to these quantitative variables and their products and sets of adequacy and goodnessof-fit criteria were used to derive individual biomass models for stem and branches. Then we developed compatible additive systems of models for stem, branch and total lignified biomass in log-transformed form. Finally, the prediction data were back-transformed, applying correction for bias, and were cross-validated. Three systems of generic equations were derived to enable flexible model implementation. Equation system M1 proposes a stem biomass model based on tree and stand heights and stem diameter, and a model for

  5. The effect of mycorrhizal inoculation on hybrid poplar fine root dynamics in hydrocarbon contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Gunderson, J.; Knight, J.D.; Van Rees, K.C.J. [Saskatchewan Univ., Saskatoon, SK (Canada). Dept. of Soil Science

    2006-07-01

    The biological remediation of contaminated soils using plants was discussed. Hybrid poplars are good candidates for phytoremediation because they root deeply, cycle large amounts of water and grow quickly. Their fine root system is pivotal in nutrient and water acquisition. Therefore, in order to maximize the phytoremediation potential, it is important to understand the response of the fine root system. In addition to degrading organic chemicals, ectomycorrhizal (ECM) fungi provide the host with greater access to nutrients. This study determined the relationship between residual soil hydrocarbons and soil properties at a field site. The effects of residual contamination on hybrid poplar fine root dynamics was also examined along with the effect of ectomycorrhizal colonization on hybrid poplar fine root dynamics when grown in diesel contaminated soil under controlled conditions. A minirhizotron camera inside a growth chamber captured images of mycorrhizal inoculation on hybrid poplar fine root production. Walker hybrid poplar seedlings were grown for 12 weeks in a control soil and also in a diesel contaminated soil. Seedlings were also grown in control and diesel contaminated, ectomycorrhizal inoculated soils. The inoculum was a mycorrhizal mix containing Pisolithus tinctorius and Rhizopogon spp. The images showed that colonization by ECM fungi increased hybrid poplar fine root production and aboveground biomass in a diesel contaminated soil compared to non-colonized trees in the same soil. Root:shoot ratios were much higher in the diesel contaminated/non-inoculated treatment than in either of the control soil treatments. Results of phytoremediation in diesel contaminated soil were better in the non-colonized treatment than in the colonized treatment. Both treatments removed more contaminants from the soil than the unplanted control. Much higher quantities of hydrocarbons were found sequestered in the roots from the inoculated treatment than from the non

  6. Biomass and nitrogen dynamics in an irrigated hybrid poplar plantation

    Energy Technology Data Exchange (ETDEWEB)

    McLaughlin, R.A.

    1985-01-01

    A 3-year study measured the effects of ground cover treatments and nitrogen fertilization on biomass and nitrogen dynamics in an irrigated hybrid poplar (Populus deltoides Bartr. x P. trichocarpa Torr. and Gray, clone NC-9922) plantation in northern Wisconsin. Annually fertilized (112 kg N/ha/yr) and unfertilized plots were either maintained weed-free (bare soil), allowed to revegetate with native weeds, or seeded to birdsfoot trefoil (Lotus corniculatus L.). Trees in bare soil plots responded to fertilization primarily in the third growing season, but total biomass of 3-year-old trees was not increased by annual fertilization. High nitrate-nitrogen concentrations in the soil solution suggested significant leaching in both unfertilized and fertilized bare soil plots in the first growing season, and in fertilized plots the second season. Nitrate-nitrogen concentrations declined sharply in fertilized bare soil plots during the third growing season. Cover crop biomass was greatest in the second year and declined thereafter due to declines in below-ground components. Fertilization increased tree growth in these plots, but cover crop treatments had no effect. Results of this study suggest that, under irrigated conditions, a cover crop can substantially reduce leaching losses of nutrients and serve as a slow-release pool of nitrogen after the trees achieve crown closure. Fertilization is not recommended in these plantations until the second growing season if a cover crop is present and the third growing season if complete weed control is practiced.

  7. Biomass and Volume Yield in Mature Hybrid Poplar Plantations on Temperate Abandoned Farmland

    Directory of Open Access Journals (Sweden)

    Benoit Truax

    2014-12-01

    Full Text Available In this study, we developed clone-specific allometric relationships, with the objective of calculating volume and biomass production after 13 years in 8 poplar plantations, located across an environmental gradient, and composed of 5 unrelated hybrid poplar clones. Allometry was found to be very similar for clones MxB-915311, NxM-3729 and DNxM-915508, all having P. maximoviczii parentage. Clones DxN-3570 and TxD-3230 also had a similar allometry; for a given DBH they have a lower stem volume, stem biomass and branch biomass than P. maximoviczii hybrids. Strong Site × Clone interactions were observed for volume and woody biomass growth, with DxN and TxD hybrids only productive on low elevation fertile sites, whereas P. maximovizcii hybrids were also very productive on higher elevation sites with moderate to high soil fertility. At the site level (5 clones mean, yield reached 27.5 and 22.7 m3/ha/yr. on the two best sites (high fertility and low elevation, confirming the great potential of southern Québec (Canada for poplar culture. The productivity gap between the most and least productive sites has widened from year 8 to year 13, highlighting the need for high quality abandoned farmland site selection in terms of climate and soil fertility. Although clone selection could optimize yield across the studied environmental gradient, it cannot fully compensate for inadequate site selection.

  8. Comparative Proteomic Analyses of the Hybrid Yellow-Poplar Stigma upon Pollination

    Institute of Scientific and Technical Information of China (English)

    Ming Li; Kun Wang; Pingfang Yang

    2012-01-01

    As basal angiosperm,Liriodendron chinense (Hemsl.) Sarg.and Liriodendron tulipifera Linn.are two species belong to Liriodendron genus.Hybrid yellowpoplar was obtained through crossing between Liriodendron tulipifera Linn.x L.chinense(Hemsl.) Sarg.Although hybrid yellow-poplar was strong in both growth and adaptation,its fruiting rate was as low as its parents.In this study,we profiled the proteome in hybrid yellow-poplar stigma before and after pollination.Comparative analyses of two dimensional gel electrophoresis maps from un-pollinated and pollinated stigmas showed that 30 proteins were increased and 27 proteins decreased after pollination.Functional categorization showed that most of them were metabolism-related,stress response related and protein biosynthesis,degradation and destinationrelated proteins.Also there were some redox-related and cell signaling-related proteins.All these changed proteins might involve in or affect the pollen and stigma interaction in hybrid yellow-poplar.This study will be helpful in understanding the regulation of Liriodendron genus sexual reproduction.

  9. Predicting yields of short-rotation hybrid poplar (Populus spp.) for the United States through model-data synthesis.

    Science.gov (United States)

    Wang, Dan; LeBauer, David; Dietze, Michael

    2013-06-01

    Hybrid poplar (Populus spp.) is an important biomass crop being evaluated for cellulosic ethanol production. Predictions of poplar growth, rotation period, and soil carbon sequestration under various growing conditions, soils, and climates are critical for farmers and managers planning to establish short-rotation forestry (SRF) plantations. In this study, we used an ecoinformatics workflow, the Predictive Ecosystem Analyzer (PEcAn), to integrate literature data and field measurements into the Ecosystem Demography 2 (ED2) model to estimate yield potential of poplar plantations. Within PEcAn 164 records of seven different traits from the literature were assimilated using a Bayesian meta-analysis. Next, variance decomposition identified seven variables for further constraint that contributed > 80% to the uncertainty in modeled yields: growth respiration, dark respiration, quantum efficiency, mortality coefficient, water conductance, fine-root allocation, and root turnover rate. Assimilation of observed yields further constrained uncertainty in model parameters (especially dark respiration and root turnover rate) and biomass estimates. Additional measurements of growth respiration, mortality, water conductance, and quantum efficiency would provide the most efficient path toward further constraint of modeled yields. Modeled validation demonstrated that ED2 successfully captured the interannual and spatial variability of poplar yield observed at nine independent sites. Site-level analyses were conducted to estimate the effect of land use change to SRF poplar on soil C sequestration compared to alternate land uses. These suggest that poplar plantations became a C sink within 18 years of conversion from corn production or existing forest. Finally, poplar yields were estimated for the contiguous United States at a half degree resolution in order to determine potential productivity, estimate the optimal rotation period, and compare poplar to perennial grass yields. This

  10. The growth process of natural poplar-birch forests

    Institute of Scientific and Technical Information of China (English)

    LAN Shibo; LUO Xu; LUO Yuliang

    2006-01-01

    With a combination of permanent and temporary sample plots,we investigated the growth conditions of natural poplar-birch forests.The forests were divided into four site classes,using statistical and analytical techniques in a quantitative model,in descending order where site class I was the best.On this basis,the growth of natural poplar-birch forests in the different site classes was studied.The growth processes of height and diameter at breast height were divided into three stages:a fast growing period,a stable growing period and a slow growing period.Results of this study provide a theoretical basis for the directive cultivation of natural poplar-birch forests.

  11. Antisense down-regulation of 4CL expression alters lignification, tree growth, and saccharification potential of field-grown poplar

    Science.gov (United States)

    Steven L. Voelker; Barbara Lachenbruch; Frederick C. Meinzer; Michael Jourdes; Chanyoung Ki; Ann M. Patten; Laurence B. Davin; Norman G. Lewis; Gerald A. Tuskan; Lee Gunter; Stephen R. Decker; Michael J. Selig; Robert Sykes; Michael E. Himmel; Peter Kitin; Olga Shevchenko; Steven H. Strauss

    2010-01-01

    Transgenic down-regulation of the Pt4CL1 gene family encoding 4-coumarate:coenzyme A ligase (4CL) has been reported as a means for reducing lignin content in cell walls and increasing overall growth rates, thereby improving feedstock quality for paper and bioethanol production. Using hybrid poplar (Populus tremula...

  12. Hybrid poplar plantations are suitable habitat for reintroduced forest herbs with conservation status.

    Science.gov (United States)

    Boothroyd-Roberts, Kathleen; Gagnon, Daniel; Truax, Benoit

    2013-01-01

    Plantations of fast-growing tree species may be of use in conservation by accelerating the restoration of forest habitat on abandoned farmland and increasing connectivity in fragmented landscapes. The objective of this study was to determine if hybrid poplar plantations can be suitable habitats for the reintroduction of native forest plant species and, if so, which abiotic factors predict successful reintroduction. Four species of forest herb species (Trillium grandiflorum, Sanguinaria canadensis, Maianthemum racemosum, Asarum canadense), of which three have legal conservation status, were transplanted into experimental plantations of two hybrid poplar clones and nearby second-growth woodlots at six sites in southern Quebec, Canada. The transplanted individuals were protected from deer browsing with exclusion cages. After two years, the plant responses of all four species were stable or increased over two years in both types of hybrid poplar plantations. Sanguinaria showed a better response in the plantations than in the woodlots, preferring the rich post-agricultural soils of the plantations with low C:N ratios. Asarum and Maianthemum showed no significant difference between stand types, while Trillium grew better in the woodlots than in the plantations. Much of the variability in the response of the latter three species was unexplained by the measured environmental variables. These results suggest that certain forest herb species can be reintroduced as juvenile plants into plantations, knowing that their spontaneous recolonization is often limited by dispersal and/or seedling establishment. Plantations could also contribute to the conservation of biodiversity by providing an environment for the cultivation of forest herb species as an alternative to their destructive harvest from natural populations.

  13. Hybrid poplar and forest soil response to municipal and industrial by-products: a greenhouse study.

    Science.gov (United States)

    Cavaleri, Molly A; Gilmore, Daniel W; Mozaffari, Morteza; Rosen, Carl J; Halbach, Thomas R

    2004-01-01

    Little research has been conducted in the Lake States (Minnesota, Wisconsin, and Michigan) to evaluate the effects of municipal and industrial by-product applications on the early growth of short rotation woody crops such as hybrid poplar. Anticipated shortages of harvestable-age aspen in the next decade can be alleviated and rural development can be enhanced through the application of by-products to forest soils. This study was conducted to evaluate the effects of inorganic fertilizer, boiler ash, biosolids, and the co-application of ash and biosolids application on tree growth and soil properties by measuring hybrid poplar clone NM-6 (Populus nigra L. x P. maximowiczii A. Henry) yield, nutrient uptake, and select post-harvest soil properties after 15 wk of greenhouse growth. Treatments included a control of no amendment; agricultural lime; inorganic N, P, and K; three types of boiler ash; biosolids application rates equivalent to 70, 140, 210, and 280 kg available N ha(-1); and boiler ash co-applied with biosolids. All of the by-products treatments showed biomass production that was equal to or greater than inorganic fertilizer and lime treatments. A trend of increased biomass with increasing rates of biosolids was observed. Soil P concentration increased with increasing rates of biosolids application. None of the by-products treatments resulted in plant tissue metal concentrations greater than metal concentrations of plant tissue amended with inorganic amendments. Biosolids, boiler ash, and the co-application of biosolids and boiler ash together on forest soils were as beneficial to plant growth as inorganic fertilizers.

  14. Efficient Agrobacterium-mediated transformation of commercial hybrid poplar Populus nigra L. x P. maximowiczii A. Henry.

    Science.gov (United States)

    Yevtushenko, Dmytro P; Misra, Santosh

    2010-03-01

    Many economically important species of Populus, especially those in sections Aigeiros and Tacamahaca, remain recalcitrant to genetic transformation. In this study, a simple and reliable protocol was developed for the efficient Agrobacterium-mediated transformation of a difficult-to-transform, but commercially viable, hybrid poplar Populus nigra L. x P. maximowiczii A. Henry (NM6). A plant transformation vector designed to express the beta-glucuronidase (GUS) gene was used to detect transformation events at early stages of plant regeneration and to optimize parameters affecting poplar transformation. The use of zeatin riboside in shoot-induction medium, regeneration of shoots via indirect organogenesis, and early selection pressure were the major modifications that drastically improved the efficiency of poplar transformation and minimized the number of untransformed regenerants. Transgenic shoots were routinely obtained 4-10 weeks after co-culture with A. tumefaciens, with a greater than 90% rate of plant recovery. Stable transgene integration, ranging from a single insertion to ten copies per genome, was confirmed by Southern blot analysis. The mean transformation frequency was 36.3% and about two-thirds of the lines had 1-2 transgene copies. Among the explants, petioles and leaves had a higher transformation frequency than did stem segments. Growth characteristics and the morphology of transgenic poplar plants were identical to untransformed controls. These findings will accelerate the development of P. nigra x P. maximowiczii plants with novel traits, and may also be useful to improve transformation procedures for other Populus species.

  15. Transgenic hybrid poplar for sustainable and scalable production of the commodity/specialty chemical, 2-phenylethanol.

    Directory of Open Access Journals (Sweden)

    Michael A Costa

    Full Text Available Fast growing hybrid poplar offers the means for sustainable production of specialty and commodity chemicals, in addition to rapid biomass production for lignocellulosic deconstruction. Herein we describe transformation of fast-growing transgenic hybrid poplar lines to produce 2-phenylethanol, this being an important fragrance, flavor, aroma, and commodity chemical. It is also readily converted into styrene or ethyl benzene, the latter being an important commodity aviation fuel component. Introducing this biochemical pathway into hybrid poplars marks the beginnings of developing a platform for a sustainable chemical delivery system to afford this and other valuable specialty/commodity chemicals at the scale and cost needed. These modified plant lines mainly sequester 2-phenylethanol via carbohydrate and other covalently linked derivatives, thereby providing an additional advantage of effective storage until needed. The future potential of this technology is discussed. MALDI metabolite tissue imaging also established localization of these metabolites in the leaf vasculature.

  16. PROPERTIES OF PARALLEL STRAND LUMBER FROM TWO HYBRID POPLAR CLONES USING MELAMINE UREA FORMALDEHYDE ADHESIVE

    Directory of Open Access Journals (Sweden)

    Ramazan Kurt,

    2012-06-01

    Full Text Available Experimental parallel strand lumbers (PSLs were manufactured from fast growing rotary peeled I-214 (Populus x euramericana and I-77/51 (Populus deltoides hybrid poplar clones veneer strands with melamine urea formaldehyde (MUF adhesive. The results showed that hybrid poplar clones can be used in PSLs manufacturing. Physical and mechanical properties of PSLs were affected by clone types. The I-77/51 clone had better properties and was found to be more suitable for PSLs manufacturing compared to the I-214 clone. PSLs properties were higher than those of solid woods (SWs and laminated veneer lumbers (LVLs of the same poplar clones. This increase may be due to materials, densification as a result of high pressure use, and the manufacturing techniques. The degree of contribution of SWs properties to the PSLs properties was lower than that of LVLs. This indicated that factors other than SWs properties played more important roles in the strength increase of PSLs.

  17. Efficient Agrobacterium-Mediated Transformation of Hybrid Poplar Populus davidiana Dode × Populus bollena Lauche

    Directory of Open Access Journals (Sweden)

    Xue Han

    2013-01-01

    Full Text Available Poplar is a model organism for high in vitro regeneration in woody plants. We have chosen a hybrid poplar Populus davidiana Dode × Populus bollena Lauche. By optimizing the Murashige and Skoog medium with (0.3 mg/L 6-benzylaminopurine and (0.08 mg/L naphthaleneacetic acid, we have achieved the highest frequency (90% for shoot regeneration from poplar leaves. It was also important to improve the transformation efficiency of poplar for genetic breeding and other applications. In this study, we found a significant improvement of the transformation frequency by controlling the leaf age. Transformation efficiency was enhanced by optimizing the Agrobacterium concentration (OD600 = 0.8–1.0 and an infection time (20–30 min. According to transmission electron microscopy observations, there were more Agrobacterium invasions in the 30-day-old leaf explants than in 60-day-old and 90-day-old explants. Using the green fluorescent protein (GFP marker, the expression of MD–GFP fusion proteins in the leaf, shoot, and root of hybrid poplar P. davidiana Dode × P. bollena Lauche was visualized for confirmation of transgene integration. Southern and Northern blot analysis also showed the integration of T-DNA into the genome and gene expression of transgenic plants. Our results suggest that younger leaves had higher transformation efficiency (~30% than older leaves (10%.

  18. Interpreting genotype‐by‐environment interaction for biomass production in hybrid poplars under short‐rotation coppice in Mediterranean environments

    National Research Council Canada - National Science Library

    Sixto, Hortensia; Gil, Paula M; Ciria, Pilar; Camps, Francesc; Cañellas, Isabel; Voltas, Jordi

    2016-01-01

    ...‐rotation coppice poplar plantations. Hybrid poplars are grown for biomass production under a wide range of climatic and edaphic conditions, but their adaptive performance in Mediterranean areas remains poorly characterized...

  19. Gaseous NO2 effects on stomatal behavior, photosynthesis and respiration of hybrid poplar leaves

    Science.gov (United States)

    In this study, we used poplar as a model plant and investigated the effects of gaseous nitrogen dioxide (NO2, 4 microliter per liter) on stomatal conductance, photosynthesis, dark- and photorespiration of Populus alba x Populus berolinensis hybrid leaves using the photosynthesis system and scanning...

  20. Evaluating hybrid poplar rooting. I. genotype x environment interactions in three contrasting sites

    Science.gov (United States)

    Ronald S., Jr. Zalesny; Don E. Riemenschneider; Richard B. Hall

    2002-01-01

    We need to learn more about environmental conditions that promote or hinder rooting of unrooted dormant hybrid poplar cuttings. Planting cuttings and recording survival after the growing season is not suitable to keep up with industrial demands for improved stock. This method does not provide information about specific genotype x environment interactions. We know very...

  1. Investigating the drought-stress response of hybrid poplar genotypes by metabolite profiling.

    Science.gov (United States)

    Barchet, Genoa L H; Dauwe, Rebecca; Guy, Robert D; Schroeder, William R; Soolanayakanahally, Raju Y; Campbell, Malcolm M; Mansfield, Shawn D

    2014-11-01

    Drought stress is perhaps the most commonly encountered abiotic stress plants experience in the natural environment, and it is one of the most important factors limiting plant productivity. Here, we employed untargeted metabolite profiling to examine four drought-stressed hybrid poplar (Populus spp.) genotypes for their metabolite content, using gas chromatography coupled to mass spectrometry. The primary objective of these analyses was to characterize the metabolite profile of poplar trees to assess relative drought resistance and to investigate the underlying biochemical mechanisms employed by the genotypes to combat drought. Metabolite profiling identified key metabolites that increased or decreased in relative abundance upon exposure to drought stress. Overall, amino acids, the antioxidant phenolic compounds catechin and kaempferol, as well as the osmolytes raffinose and galactinol exhibited increased abundance under drought stress, whereas metabolites involved in photorespiration, redox regulation and carbon fixation showed decreased abundance under drought stress. One clone in particular, Okanese, displayed unique responses to the imposed drought conditions. This clone was found to have higher leaf water potential, but lower growth rate relative to the other clones tested. Okanese also had lower accumulation of osmolytes such as raffinose, galactinol and proline, but higher overall levels of antioxidants such as catechin and dehydroascorbic acid. As such, it was proposed that osmotic adjustment as a mechanism for drought avoidance in this clone is not as well developed in comparison with the other clones investigated in this study, and that a possible alternative mechanism for the enhanced drought avoidance displayed by Okanese may be due to differential allocation of resources or better retention of water.

  2. Biochar as a substitute for vermiculite in potting mix for hybrid poplar

    Science.gov (United States)

    William L. Headlee; Catherine E. Brewer; Richard B. Hall

    2014-01-01

    The purpose of this study was to evaluate biochar as a substitute for vermiculite in potting mixes for unrooted vegetative cuttings of hybrid poplar as represented by the clone ‘NM6’ (Populus nigra L. × Populus suaveolens Fischer subsp. maximowiczii A. Henry). We compared three treatments (peat moss (control), peat moss mixed with vermiculite, and peat moss mixed with...

  3. Exploring the Role of Plant Genetics to Enhance Soil Carbon Sequestration in Hybrid Poplar Plantations

    Science.gov (United States)

    Wullschleger, S. D.; Garten, C. T.; Classen, A. T.

    2008-12-01

    Atmospheric CO2 concentrations have increased in recent decades and are projected to increase even further during the coming century. These projections have prompted scientists and policy-makers to consider how plants and soils can be used to stabilize CO2 concentrations. Although storing carbon in terrestrial ecosystems represents an attractive near-term option for mitigating rising atmospheric CO2 concentrations, enhancing the sequestration potential of managed systems will require advancements in understanding the fundamental mechanisms that control rates of carbon transfer and turnover in plants and soils. To address this challenge, a mathematical model was constructed to evaluate how changes in particular plant traits and management practices could affect soil carbon storage beneath hybrid poplar (Populus) plantations. The model was built from four sub-models that describe aboveground biomass, root biomass, soil carbon dynamics, and soil nitrogen transformations for trees growing throughout a user-defined rotation. Simulations could be run over one or multiple rotations. A sensitivity analysis of the model indicated changes in soil carbon storage were affected by variables that could be linked to hybrid poplar traits like rates of aboveground production, partitioning of carbon to coarse and fine roots, and rates of root decomposition. A higher ratio of belowground to aboveground production was especially important and correlated directly with increased soil carbon storage. Faster decomposition rates for coarse and fine dead roots resulted in a greater loss of carbon to the atmosphere as CO2 and less residual organic carbon for transfer to the fast soil carbon pool. Hence, changes in root chemistry that prolonged dead root decomposition rates, a trait that is under potential genetic control, were predicted to increase soil carbon storage via higher soil carbon inputs. Nitrogen limitation of both aboveground biomass production and soil carbon sequestration was

  4. In vitro shoot regeneration from leaf mesophyll protoplasts of hybrid poplar (Populus nigra x P. maximowiczii).

    Science.gov (United States)

    Park, Y G; Son, S H

    1992-02-01

    Protoplasts were isolated from leaf mesophyll of hybrid poplar (Populus nigra X P. maximowiczii) with a mean yield of 10.4 x 10(6) protoplasts per g fresh weight using 2.0% Cellulase 'Onozuka' R-10, 0.8% Macerozyme R-10, 1.2% Hemicellulase, 2.0% Driselase, and 0.05% Pectolyase Y-23 with CPW salts solution containing 0.6 M mannitol, 0.002 M DTT, 3 mM MES at pH 5.6. A liquid plating method produced the highest frequency of dividing protoplasts (48.6%) using an MS medium without NH4NO3. The highest percent of colony formation was 22.8%, produced with fabric supported semi-solid (0.5% w/v) agar plating method using the same culture medium. Growing cell colonies and/or micro-calli were transferred to a fresh semisolid agar medium containing 0.44 μM BAP and 9.0 μM 2,4-D. Multiple shoots were produced from protoplast-derived callus after culture on MS medium containing 6.8 μM zeatin. After root induction on half-strength MS medium that lacked growth regulators, shoots were transferred to pots containing artificial soil mix.

  5. Cellulose and lignin biosynthesis is altered by ozone in wood of hybrid poplar (Populus tremula × alba).

    Science.gov (United States)

    Richet, Nicolas; Afif, Dany; Huber, Françoise; Pollet, Brigitte; Banvoy, Jacques; El Zein, Rana; Lapierre, Catherine; Dizengremel, Pierre; Perré, Patrick; Cabané, Mireille

    2011-06-01

    Wood formation in trees is a dynamic process that is strongly affected by environmental factors. However, the impact of ozone on wood is poorly documented. The objective of this study was to assess the effects of ozone on wood formation by focusing on the two major wood components, cellulose and lignin, and analysing any anatomical modifications. Young hybrid poplars (Populus tremula × alba) were cultivated under different ozone concentrations (50, 100, 200, and 300 l l(-1)). As upright poplars usually develop tension wood in a non-set pattern, the trees were bent in order to induce tension wood formation on the upper side of the stem and normal or opposite wood on the lower side. Biosynthesis of cellulose and lignin (enzymes and RNA levels), together with cambial growth, decreased in response to ozone exposure. The cellulose to lignin ratio was reduced, suggesting that cellulose biosynthesis was more affected than that of lignin. Tension wood was generally more altered than opposite wood, especially at the anatomical level. Tension wood may be more susceptible to reduced carbon allocation to the stems under ozone exposure. These results suggested a coordinated regulation of cellulose and lignin deposition to sustain mechanical strength under ozone. The modifications of the cellulose to lignin ratio and wood anatomy could allow the tree to maintain radial growth while minimizing carbon cost.

  6. Habituation to thaxtomin A in hybrid poplar cell suspensions provides enhanced and durable resistance to inhibitors of cellulose synthesis

    Directory of Open Access Journals (Sweden)

    Beaulieu Carole

    2010-12-01

    Full Text Available Abstract Background Thaxtomin A (TA, a phytotoxin produced by the phytopathogen Streptomyces scabies, is essential for the development of potato common scab disease. TA inhibits cellulose synthesis but its actual mode of action is unknown. Addition of TA to hybrid poplar (Populus trichocarpa x Populus deltoides cell suspensions can activate a cellular program leading to cell death. In contrast, it is possible to habituate hybrid poplar cell cultures to grow in the presence of TA levels that would normally induce cell death. The purpose of this study is to characterize TA-habituated cells and the mechanisms that may be involved in enhancing resistance to TA. Results Habituation to TA was performed by adding increasing levels of TA to cell cultures at the time of subculture over a period of 12 months. TA-habituated cells were then cultured in the absence of TA for more than three years. These cells displayed a reduced size and growth compared to control cells and had fragmented vacuoles filled with electron-dense material. Habituation to TA was associated with changes in the cell wall composition, with a reduction in cellulose and an increase in pectin levels. Remarkably, high level of resistance to TA was maintained in TA-habituated cells even after being cultured in the absence of TA. Moreover, these cells exhibited enhanced resistance to two other inhibitors of cellulose biosynthesis, dichlobenil and isoxaben. Analysis of gene expression in TA-habituated cells using an Affymetrix GeneChip Poplar Genome Array revealed that durable resistance to TA is associated with a major and complex reprogramming of gene expression implicating processes such as cell wall synthesis and modification, lignin and flavonoid synthesis, as well as DNA and chromatin modifications. Conclusions We have shown that habituation to TA induced durable resistance to the bacterial toxin in poplar cells. TA-habituation also enhanced resistance to two other structurally

  7. Relationship between plant hormone level excreted by ectomycorrhizal fungi and growth of poplar NL-895

    Institute of Scientific and Technical Information of China (English)

    Lei MA; Xiaoqin WU; Ling ZHENG

    2009-01-01

    To explore the effects of plant hormones levels excreted by ectomycorrhizal (ECM) fungi on the growth of poplars, Populus x euramericana cv. NL-895 seedlings were inoculated with nine species of ECM fungi. We investigated the status of ectomycorrhizal formation and the effects of these fungi on poplar growth, and using the HPLC method, we measured the contents of four kinds of plant hormones, indole acetic acid (IAA), zeatin (Z), gibberellin (GA) and abscisic acid (ABA) in both the culture filtrate and the mycelium of these fungi. The results showed that the effects of nine ECM fungi on the growth of poplar NL-895 varied. The inoculated seedlings, whether or not obvious mycorrhizas were developed, grew better than those non-inoculated ones. All nine ectomycorrhizal fungi excreted the four plant hormones, but at different levels. The hormone contents in culture filtrate were higher than that in mycelium, which showed a definite relationship with poplar growth. Significantly, correlation analysis suggested the height and stem diameter of the poplar were positively correlated with zeatin contents in the mycelium, and were negatively correlated with the levels of ABA or IAA in the mycelium.

  8. Water consumption and biomass production of protoplast fusion lines of poplar hybrids under drought stress

    Directory of Open Access Journals (Sweden)

    Anne eHennig

    2015-05-01

    Full Text Available Woody crops such as poplars (Populus can contribute to meet the increasing energy demand of a growing human population and can therefore enhance the security of energy supply. Using energy from biomass increases ecological sustainability as biomass is considered to play a pivotal role in abating climate change. Because areas for establishing poplar plantations are often confined to marginal sites drought tolerance is one important trait for poplar genotypes cultivated in short rotation coppice. We tested nine-month-old plants of four tetraploid Populus tremula (L. x P. tremuloides (Michx. lines that were generated by protoplast fusion and their diploid counterpart for water consumption and drought stress responses in a greenhouse experiment. The fusion lines showed equivalent or decreased height growth, stem biomass and total leaf area compared to the diploid line. The relative height increment of the fusion lines was not reduced compared to the diploid line when the plants were exposed to drought. The fusion lines were distinguished from the diploid counterpart by stomatal characteristics such as increased size and lower density. The changes in the stomatal apparatus did not affect the stomatal conductance. When exposed to drought the carbohydrate concentrations increased more strongly in the fusion lines than in the diploid line. Two fusion lines consumed significantly less water with regard to height growth, producing equivalent or increased relative stem biomass under drought compared to their diploid relative. Therefore, these tetraploid fusion lines are interesting candidates for short rotation biomass plantation on dry sites.

  9. Water consumption and biomass production of protoplast fusion lines of poplar hybrids under drought stress.

    Science.gov (United States)

    Hennig, Anne; Kleinschmit, Jörg R G; Schoneberg, Sebastian; Löffler, Sonja; Janßen, Alwin; Polle, Andrea

    2015-01-01

    Woody crops such as poplars (Populus) can contribute to meet the increasing energy demand of a growing human population and can therefore enhance the security of energy supply. Using energy from biomass increases ecological sustainability as biomass is considered to play a pivotal role in abating climate change. Because areas for establishing poplar plantations are often confined to marginal sites drought tolerance is one important trait for poplar genotypes cultivated in short rotation coppice. We tested 9-month-old plants of four tetraploid Populus tremula (L.) × P. tremuloides (Michx.) lines that were generated by protoplast fusion and their diploid counterpart for water consumption and drought stress responses in a greenhouse experiment. The fusion lines showed equivalent or decreased height growth, stem biomass and total leaf area compared to the diploid line. The relative height increment of the fusion lines was not reduced compared to the diploid line when the plants were exposed to drought. The fusion lines were distinguished from the diploid counterpart by stomatal characteristics such as increased size and lower density. The changes in the stomatal apparatus did not affect the stomatal conductance. When exposed to drought the carbohydrate concentrations increased more strongly in the fusion lines than in the diploid line. Two fusion lines consumed significantly less water with regard to height growth, producing equivalent or increased relative stem biomass under drought compared to their diploid relative. Therefore, these tetraploid fusion lines are interesting candidates for short rotation biomass plantation on dry sites.

  10. Land use and wind direction drive hybridization between cultivated poplar and native species in a Mediterranean floodplain environment.

    Science.gov (United States)

    Paffetti, Donatella; Travaglini, Davide; Labriola, Mariaceleste; Buonamici, Anna; Bottalico, Francesca; Materassi, Alessandro; Fasano, Gianni; Nocentini, Susanna; Vettori, Cristina

    2018-01-01

    Deforestation and intensive land use management with plantations of fast-growing tree species, like Populus spp., may endanger native trees not only by eliminating or reducing their habitats, but also by diminishing their species integrity via hybridization and introgression. The genus Populus has persistent natural hybrids because clonal and sexual reproduction is common. The objective of this study was to assess the effect of land use management of poplar plantations on the spatial genetic structure and species composition in poplar stands. Specifically, we studied the potential breeding between natural and cultivated poplar populations in the Mediterranean environment to gain insight into spontaneous hybridization events between exotic and native poplars; we also used a GIS-based model to evaluate the potential threats related to an intensive land use management. Two study areas, both near to poplar plantations (P.×euramericana), were designated in the native mixed stands of P. alba, P. nigra and P.×canescens within protected areas. We found that the spatial genetic structure differed between the two stands and their differences depended on their environmental features. We detected a hybridization event with P.×canescens that was made possible by the synchrony of flowering between the poplar plantation and P.×canescens and facilitated by the wind intensity and direction favoring the spread of pollen. Taken together, our results indicate that natural and artificial barriers are crucial to mitigate the threats, and so they should be explicitly considered in land use planning. For example, our results suggest the importance of conserving rows of trees and shrubs along rivers and in agricultural landscapes. In sum, it is necessary to understand, evaluate, and monitor the spread of exotic species and genetic material to ensure effective land use management and mitigation of their impact on native tree populations. Copyright © 2017 Elsevier B.V. All rights

  11. SUITABILITY OF THREE HYBRID POPLAR CLONES FOR LAMINATED VENEER LUMBER MANUFACTURING USING MELAMINE UREA FORMALDEHYDE ADHESIVE

    Directory of Open Access Journals (Sweden)

    Ramazan Kurt

    2010-07-01

    Full Text Available Experimental laminated veneer lumbers (LVLs from rotary peeled I-214 (Populus x Euramericana and two Populus deltoides I-77/51 and S.307-26 fast growing hybrid poplar clones were manufactured with a melamine urea formaldehyde (MUF adhesive successfully. Two Populus deltoides clones that are grown in Turkey were used for the first time in LVLs manufacturing. The results showed that clone types affected physical and mechanical properties of LVLs. Populus deltoides clones had better physical and mechanical properties compared to Populus x Euramericana clone due to their higher density and fiber length values. S.307-26 clone had the highest and I-214 had the lowest properties among three hybrid poplar clones. The physical and mechanical properties of LVLs were higher than those of solid woods. This increase may be due to compaction factor (densification, manufacturing techniques, and the use of adhesives. The degree of contribution of solid wood properties to the LVLs’ properties was explained by using a contribution factor. Two Populus deltoides clones were found to be more suitable for LVLs manufacturing compared to Populus x Euramericana clone.

  12. Soil Carbon Stocks in Two Hybrid Poplar-Hay Crop Systems in Southern Quebec, Canada

    Directory of Open Access Journals (Sweden)

    Kiara Winans

    2014-08-01

    Full Text Available Tree-based intercropping (TBI systems, consisting of a medium to fast-growing woody species planted in widely-spaced rows with crops cultivated between tree rows, are a potential sink for atmospheric carbon dioxide (CO2. TBI systems contribute to farm income in the long-term by improving soil quality, as indicated by soil carbon (C storage, generating profits from crop plus tree production and potentially through C credit trading. The objectives of the current study were: (1 to evaluate soil C and nitrogen (N stocks in soil depth increments in the 0–30 cm layer between tree rows of nine-year old hybrid poplar-hay intercropping systems, to compare these to C and N stocks in adjacent agricultural systems; and (2 to determine how hay yield, litterfall and percent total light transmittance (PTLT were related to soil C and N stocks between tree rows and in adjacent agricultural systems. The two TBI study sites (St. Edouard and St. Paulin had a hay intercrop with alternating rows of hybrid poplar clones and hardwoods and included an adjacent agricultural system with no trees (i.e., the control plots. Soil C and N stocks were greater in the 0–5 cm depth increment of the TBI system within 1 m of the hardwood row, to the west of the poplar row, compared to the sampling point 1 m east of poplar at St. Edouard (p = 0.02. However, the agricultural system stored more soil C than the nine-year old TBI system in the 20–30 cm and 0–30 cm depth increments. Accumulation of soil C in the 20–30 cm depth increment could be due to tillage-induced burial of non-harvested crop residues at the bottom of the plow-pan. Soil C and N stocks were similar at all depth increments in TBI and agricultural systems at St. Paulin. Soil C and N stocks were not related to hay yield, litterfall and PTLT at St. Paulin, but hay yield and PTLT were significantly correlated (R = 0.87, p < 0.05, n = 21, with lower hay yield in proximity to trees in the TBI system and similar hay

  13. Comparing growth rate in a mixed plantation (walnut, poplar and nurse trees with different planting designs: results from an experimental plantation in northern Italy

    Directory of Open Access Journals (Sweden)

    Francesco Pelleri

    2013-12-01

    Full Text Available 800x600 Results of a mixed plantation with poplar, walnut and nurse trees established in winter 2003 in Northern Italy, are reported. Main tree species (poplar and walnut were planted according to a rectangular design (10 x 11m, with different spacings and alternate lines. The experimental trial was carried out to verify the following working hypotheses: (i possibility to combine main trees with different growth levels (common walnut, hybrid walnut, and different poplar clones and test two different poplar and walnut spacings (5.0 and 7.4 m in the same plantation; (ii opportunity to reduce cultivation’s workload, in comparison with poplar monoculture, using mixtures with different poplar clones and N-fixing nurse trees; (iii verifying the growth pattern of two new poplar clones in comparison with the traditional clones cultivated for different purposes in Italy.The use of different valuable crop trees’ mixtures intercropped with nurse trees and shrubs (including N-fixing trees allows to decrease the cultivation’s workload. In fact, a heavy reduction of cultural practices - fertilizers, weed control, irrigation and pesticides applications (-61% are the main concurrent, supplementary benefits. The best growth performances (DBH and tree height, associated with the higher competition towards walnuts, were recorded with the new clones Lena and Neva in comparison with the I214 and Villafranca. The closer spacing (5 m between poplar and walnut trees was found to be unsuited to get merchantable poplars sized 30 cm without developing a heavy competition towards walnut trees. The wider spacing (7.4 m resulted vice versa suitable to get poplar trees sized as requested by veneer factories and to maintain an acceptable competitive level with walnut. Within this plantation design, a shorter rotation (8 yrs is needed for Lena and Neva clones in comparison with I214 and Villafranca (10 yrs. Walnut intercropped with poplar showed cone-shaped crowns, light

  14. Phasing Variants in Poplar Trees using a Hybrid of Short & Long Read Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Schackwitz, Wendy; Martin, Joel; Lipzen, Anna; Pennacchio, Len; Tuskan, Gerald

    2013-03-26

    Poplar grow throughout the West coast & are adapted to extremely variable conditions. To examine what allows for this wide range of growth conditions, Jerry Tuskan's team has collected 1000 different individuals from British Columbia to California. In 2009, three Common Gardens were established where each individual was cloned in triplicate. Nearly all of these trees have been sequenced using short read technology, revealing a huge degree of variation in genotype. Correlating this genomic variation to phenotype would be greatly be strengthened if the variants could be phased into long haplotype blocks.

  15. Clone-Specific Response in Leaf Nitrate Reductase Activity among Unrelated Hybrid Poplars in relation to Soil Nitrate Availability

    Directory of Open Access Journals (Sweden)

    Julien Fortier

    2012-01-01

    Full Text Available In this field study, we used in vivo NRA activity in hybrid poplar leaves as an indicator of NO3- assimilation for five unrelated hybrid poplar clones. We also examined if leaf NRA of these clones is influenced to the same extent by different levels of soil NO3- availability in two riparian agroforestry systems located in pastures. Leaf NRA differences of more than one order of magnitude were observed between the clones, clearly showing their different abilities to reduce NO3- in leaves. Clone DxN-3570, a P. deltoides x P. nigra hybrid (Aigeiros intrasectional hybrid, always had the highest leaf NRA during the field assays. This clone was also the only one to increase its leaf NRA with increasing NO3- soil availability, which resulted in a significant Site x Clone interaction and a positive relationship between soil NO3- concentration and NRA. All of the four other clones studied had one or both parental species from the Tacamahaca section. They had relatively low leaf NRA and they did not increase their leaf NRA when grown on the NO3- rich site. These results provide evidence that NO3- assimilation in leaves varies widely among hybrid poplars of different parentages, suggesting potential preferences for N forms.

  16. Uptake and Translocation of Lesser-Chlorinated Polychlorinated Biphenyls (PCBs) in Whole Hybrid Poplar Plants after Hydroponic Exposure

    Science.gov (United States)

    Liu, Jiyan; Schnoor, Jerald L.

    2009-01-01

    Mono-, di-, tri-, and tetra-chlorinated polychlorinated biphenyls (PCBs) are congeners with greater volatility which remain in air, soils and sediments requiring treatment. In this study, the fate of these PCBs was investigated within whole poplar plants (Populus deltoides x nigra, DN34) with application for a treatment system such as a confined disposal facility for dredged material. Whole hybrid poplars were exposed hydroponically to a mixture of five congeners, common in the environment, having one to four chlorine atoms per molecule. Results indicated that PCB 3, 15, 28, 52, and 77 were initially sorbed to the root systems. The Root Concentration Factor (RCF) of PCBs during the exposure was calculated and correlated with Kow. PCB congeners were taken up by the roots of hybrid poplar, and the translocation of PCBs to stems was inversely related to congener hydrophobicity (Log Kow). PCB 3 and 15 were translocated to the upper stem at small but significant rates. PCB 28 was translocated to the wood of the main stem but no farther; translocation from the roots was not detected for PCB 52 and 77. The distribution of PCBs within poplars was determined, and mass balances were completed to within 15% for each chemical except for PCB 3, the most volatile congener. This is the first report on the transport of PCBs through whole plants designed for use in treatment at disposal facilities. PMID:18793792

  17. Potential for Hybrid Poplar Riparian Buffers to Provide Ecosystem Services in Three Watersheds with Contrasting Agricultural Land Use

    Directory of Open Access Journals (Sweden)

    Julien Fortier

    2016-02-01

    Full Text Available In temperate agricultural watersheds, the rehabilitation of tree vegetation in degraded riparian zones can provide many ecosystem services. This study evaluated ecosystem service provision potential following the conversion of non-managed herbaceous buffers to hybrid poplar (Populus spp. buffers in three watersheds (555–771 km2 of southern Québec (Canada, with contrasting agricultural land uses. To extrapolate services at the watershed level, total stream length where hybrid poplars could be established was calculated using GIS data from hydrological and land cover maps. After nine years, a 100% replacement of herbaceous buffers by hybrid poplar buffers along farm streams could lead to the production of 5280–76,151 tons of whole tree (stems + branches biomass, which could heat 0.5–6.5 ha of greenhouses for nine years, with the potential of displacing 2–29 million litres of fuel oil. Alternatively, the production of 3887–56,135 tons of stem biomass (fuelwood could heat 55–794 new farmhouses or 40–577 old farmhouses for nine years. Producing fuelwood in buffers rather than in farm woodlots could create forest conservation opportunities on 300–4553 ha. Replacing all herbaceous buffers by poplar buffers could provide potential storage of 2984–42,132 t C, 29–442 t N and 3–56 t P in plant biomass, if woody biomass is not harvested. The greatest potential for services provision was in the Pike River watershed where agriculture is the dominant land use. A review of the potential services of poplar buffers is made, and guidelines for managing services and disservices are provided.

  18. Dinamica şi caracteristicile creşterii a şase clone de plop hibrid pe parcursul unui ciclu de producţie într-o plantație comparativă din Depresiunea Rădăuţi [The dynamics and growth characteristics of six hybrid poplar clones during a production cycle in a comparative plantation from Rădăuți Depression

    Directory of Open Access Journals (Sweden)

    Dănilă Iulian

    2015-08-01

    Full Text Available The poplar (Populus spp. plays an important role in worldwide forest economy, responding to the necessities of obtaining high biomass production in a short time. Short rotation forests (SRF are developing continuously in Romania. Several studies have been undertaken to identify the clones with high productivity and suitable technologies. The aim of this study was to register the annual increments in diameter, height and volume in an experimental poplar crops with a short-term rotation of 5 years. The poplar cultures are composed from 6 types of hybrid poplar clones (AF2, AF6, Monviso, A4A, Pannonia and Max4 with a density of 2667 trees ha-1. The research results show a clear differentiation among clones’ increments. The highest increments were obtained with AF2 and AF6 clones in five years, with almost 0.038 m3 an-1. The lowest increment was observed for Max4 clone with 0.028 m3.

  19. Wutun Poplar growth in South of Xinjiang%吴屯杨在南疆的生长状况研究

    Institute of Scientific and Technical Information of China (English)

    丁晓丽; 易海艳; 杨盼盼

    2015-01-01

    Determination of annual Xinjiang poplar Wutun poplar under the same conditions, the growth indica-tors, the results show that the Wutun poplar implanted in 4436, 342 died, Wutun poplar's survival rate was 92.3%, while Xinjiang poplar implanted in 4399, 513 died, Xinjiang poplar survival rate was 88.3%.Through the investi-gation of Wutun poplar, and Xinjiang poplar plant height, diameter, diameter at breast height and found that Wutun poplar both plant height, basal diameter, diameter at breast height of these growth indicators are excellent and the Xinjiang poplar, so it can be concluded in the same habitatunder Wutun poplar faster than Xinjiang poplar growth rate, the overall growth is relatively stable, the resistance of fast-growing Wutun poplar introduction to the southern border is feasible.%通过对一年生的新疆杨与吴屯杨在同一条件下的生长指标测定,结果表明,吴屯杨共植入4436株,死亡342株,吴屯杨的成活率为92.3%;而新疆杨共植入4399株,死亡513株,新疆杨的成活率为88.3%.通过调查吴屯杨和新疆杨的株高、地径、胸径,发现吴屯杨无论是株高、地径、胸径这些生长指标都优与新疆杨,因此在同一生境下吴屯杨比新疆杨生长速率更快,整体生长比较稳定,抗逆性速生吴屯杨引种至南疆具有可行性.

  20. Effects of Cutting Density on Growth,Yield and Quality of Poplar Clone Seedlings

    Institute of Scientific and Technical Information of China (English)

    Fang Shengzuo; Tian Ye; Yuan Fayin

    2006-01-01

    In order to identify the optimum cutting density for producing the highest number of plantable seedlings of poplar clones,a split-plot randomized block design was used to establish four cutting densities in plots.Based on data on the survival,leaf area,seedling height,caliper,and biomass of 1-year-old seedlings of clones Nanlin-95,Nanlin-895,Nanlin-1388 and NL-80351,the growth characteristics and seedling quality under four cutting densities were analyzed.Results indicated that the leaf area,stern and leaf biomass,and caliper of seedlings of all four poplar clones increased with the decrease in cutting density.Leaf area index reached its highest level at the spacing of 40 cm×40 cm,while the aboveground biomass of the seedling on an area basis increased as the cutting density increased.Seedling quality at low cutting density was higher than that at closer cutting density.The quantity of first-grade seedlings (grade Ⅰ) for clones Nanlin-95 and Nanlin-895 was achieved at the spacing of 40 cm×50 cm;for NL-1388 and NL-80351,it was 50 cm×50 cm.According to the seedling quality and the number of plantable seedlings produced,the suggested cutting density for these four poplar clones was 50,000 stems/hm2.

  1. Overexpression of poplar cellulase accelerates growth and disturbs the closing movements of leaves in sengon.

    Science.gov (United States)

    Hartati, Sri; Sudarmonowati, Enny; Park, Yong Woo; Kaku, Tomomi; Kaida, Rumi; Baba, Kei'ichi; Hayashi, Takahisa

    2008-06-01

    In this study, poplar (Populus alba) cellulase (PaPopCel1) was overexpressed in a tropical Leguminosae tree, sengon (Paraserianthes falcataria), by the Agrobacterium tumefaciens method. PaPopCel1 overexpression increased the length and width of stems with larger leaves, which showed a moderately higher density of green color than leaves of the wild type. The pairs of leaves on the transgenic plants closed more slowly during sunset than those on the wild-type plants. When main veins from each genotype were excised and placed on a paper towel, however, the leaves of the transgenic plants closed more rapidly than those of the wild-type plant. Based on carbohydrate analyses of cell walls, the leaves of the transgenic plants contained less wall-bound xyloglucan than those of the wild-type plants. In situ xyloglucan endotransglucosylase activity showed that the incorporation of whole xyloglucan, potentially for wall tightening, occurred in the parenchyma cells (motor cells) of the petiolule pulvinus attached to the main vein, although the transgenic plant incorporated less whole xyloglucan than the wild-type plant. These observations support the hypothesis that the paracrystalline sites of cellulose microfibrils are attacked by poplar cellulase, which loosens xyloglucan intercalation, resulting in an irreversible wall modification. This process could be the reason why the overexpression of poplar cellulase both promotes plant growth and disturbs the biological clock of the plant by altering the closing movements of the leaves of the plant.

  2. Early differentiation in biomass production and carbon sequestration of white poplar and its two hybrids in Central Iran

    Institute of Scientific and Technical Information of China (English)

    Hormoz Sohrabi; Mohammad Kazem Parsapour; Ali Soltani; Yaghoub Iranmanesh

    2015-01-01

    We assessed the potential of white poplar (Populus alba L.) and its inter-sectional hybridization with euphrates poplar (P. euphratica Oliv.) for carbon storage and sequestration in central Iran. Trials were established at planting density of 2,500 trees per hectare in block ran-domized design with three replicates. After 6 years, we measured the above-ground biomass of tree components (trunk, branch, bark, twig and leaf), and assessed soil carbon at three depths. P. alba × euphratica plantation stored significantly more carbon (22.3 t ha-1) than P. alba (16.7 t ha-1) and P. euphratica × alba (13.1 t ha-1). Most of the carbon was accumulated in the above-ground biomass (61.1%in P. alba, 72.4%in P. alba × euphra-tica and 56.0% in P. euphratica × alba). There was no significant difference in soil carbon storage. Also, biomass allocation was different between white poplar P. alba and its inter-sectional hybridization. Therefore, there was a yield difference due to genomic imprinting, which increased the possibility that paternally and maternally inherited wood production alleles would be differentially expressed in the new crossing.

  3. Allometric Biomass, Biomass Expansion Factor and Wood Density Models for the OP42 Hybrid Poplar in Southern Scandinavia

    DEFF Research Database (Denmark)

    Nielsen, Anders Tærø; Nord-Larsen, Thomas; Stupak, Inge

    2015-01-01

    Biomass and biomass expansion factor functions are important in wood resource assessment, especially with regards to bioenergy feedstocks and carbon pools. We sampled 48 poplar trees in seven stands with the purpose of estimating allometric models for predicting biomass of individual tree...... components, stem-to-aboveground biomass expansion factors (BEF) and stem basic densities of the OP42 hybrid poplar clone in southern Scandinavia. Stand age ranged from 3 to 31 years, individual tree diameter at breast height (dbh) from 1.2 to 41 cm and aboveground tree biomass from 0.39 to 670 kg. Models...... for predicting total aboveground leafless, stem and branch biomass included dbh and tree height as predictor variables and explained more than 97 % of the total variation. The BEF was approaching 2.0 for the smallest trees but declined with increasing tree size and stabilized around 1.2 for trees with dbh >10 cm...

  4. Post-treatment mechanical refining as a method to improve overall sugar recovery of steam pretreated hybrid poplar.

    Science.gov (United States)

    Dou, Chang; Ewanick, Shannon; Bura, Renata; Gustafson, Rick

    2016-05-01

    This study investigates the effect of mechanical refining to improve the sugar yield from biomass processed under a wide range of steam pretreatment conditions. Hybrid poplar chips were steam pretreated using six different conditions with or without SO2. The resulting water insoluble fractions were subjected to mechanical refining. After refining, poplar pretreated at 205°C for 10min without SO2 obtained a 32% improvement in enzymatic hydrolysis and achieved similar overall monomeric sugar recovery (539kg/tonne) to samples pretreated with SO2. Refining did not improve hydrolyzability of samples pretreated at more severe conditions, nor did it improve the overall sugar recovery. By maximizing overall sugar recovery, refining could partially decouple the pretreatment from other unit operations, and enable the use of low temperature, non-sulfur pretreatment conditions. The study demonstrates the possibility of using post-treatment refining to accommodate potential pretreatment process upsets without sacrificing sugar yields.

  5. Enhancement of Lignin Biopolymer Isolation from Hybrid Poplar by Organosolv Pretreatments

    Directory of Open Access Journals (Sweden)

    Miao Wu

    2014-01-01

    Full Text Available Lignocellulosic biomass is an abundant renewable resource that has the potential to displace petroleum in the production of biomaterials and biofuels. In the present study, the fractionation of different lignin biopolymers from hybrid poplar based on organosolv pretreatments using 80% aqueous methanol, ethanol, 1-propanol, and 1-butanol at 220°C for 30 min was investigated. The isolated lignin fractions were characterized by Fourier transform infrared spectroscopy (FT-IR, high-performance anion exchange chromatography (HPAEC, 2D nuclear magnetic resonance (2D NMR, and thermogravimetric analysis (TGA. The results showed that the lignin fraction obtained with aqueous ethanol (EOL possessed the highest yield and the strongest thermal stability compared with other lignin fractions. In addition, other lignin fractions were almost absent of neutral sugars (1.16–1.46% though lignin preparation extracted with 1-butanol (BOL was incongruent (7.53%. 2D HSQC spectra analysis revealed that the four lignin fractions mainly consisted of β-O-4′ linkages combined with small amounts of β-β′ and β-5′ linkages. Furthermore, substitution of Cα in β-O-4′ substructures had occurred due to the effects of dissolvent during the autocatalyzed alcohol organosolv pretreatments. Therefore, aqueous ethanol was found to be the most promising alcoholic organic solvent compared with other alcohols to be used in noncatalyzed processes for the pretreatment of lignocellulosic biomass in biorefinery.

  6. Genome survey and characterization of endophytic bacteria exhibiting a beneficial effect on growth and development of poplar trees.

    Science.gov (United States)

    Taghavi, Safiyh; Garafola, Craig; Monchy, Sébastien; Newman, Lee; Hoffman, Adam; Weyens, Nele; Barac, Tanja; Vangronsveld, Jaco; van der Lelie, Daniel

    2009-02-01

    The association of endophytic bacteria with their plant hosts has a beneficial effect for many different plant species. Our goal is to identify endophytic bacteria that improve the biomass production and the carbon sequestration potential of poplar trees (Populus spp.) when grown in marginal soil and to gain an insight in the mechanisms underlying plant growth promotion. Members of the Gammaproteobacteria dominated a collection of 78 bacterial endophytes isolated from poplar and willow trees. As representatives for the dominant genera of endophytic gammaproteobacteria, we selected Enterobacter sp. strain 638, Stenotrophomonas maltophilia R551-3, Pseudomonas putida W619, and Serratia proteamaculans 568 for genome sequencing and analysis of their plant growth-promoting effects, including root development. Derivatives of these endophytes, labeled with gfp, were also used to study the colonization of their poplar hosts. In greenhouse studies, poplar cuttings (Populus deltoides x Populus nigra DN-34) inoculated with Enterobacter sp. strain 638 repeatedly showed the highest increase in biomass production compared to cuttings of noninoculated control plants. Sequence data combined with the analysis of their metabolic properties resulted in the identification of many putative mechanisms, including carbon source utilization, that help these endophytes to thrive within a plant environment and to potentially affect the growth and development of their plant hosts. Understanding the interactions between endophytic bacteria and their host plants should ultimately result in the design of strategies for improved poplar biomass production on marginal soils as a feedstock for biofuels.

  7. Root proteome response to growth on tannery waste in three different poplar species with various adaptation abilities

    Directory of Open Access Journals (Sweden)

    Zemleduch-Barylska A.

    2013-04-01

    Full Text Available In our study we compared growth of three poplar clones (Populus tremula ×alba, P. alba ‘Villafranca” and P. nigra on chromium-containing solid tannery waste. Tolerance index of saplings ranged from only 25% for P. nigra up to 80% for P. tremula x alba. Standard morphological, chemical and biochemical analyses also confirmed significant differences in reaction of all tested clones to such growth conditions. Preliminary proteomic study showed an unequal level of changes in protein profiles from roots in different poplars.

  8. Histological characterization of gell formation and lesion development on leaves of Phaseolus vulgaris and clones of hybrid poplar after exposure to simulated sulfate acid rain

    Energy Technology Data Exchange (ETDEWEB)

    Dacosta, F.

    1978-01-01

    Histological investigations with leaves of several hybrid poplar clones illustrate gall formations in response to simulated acid rain that result from hyperplasia and hypertrophy of mesophyll cells. Similar experiments with phaseolus vulgaris and clones of hybrid poplar show a sequence of events that follow a general pattern of adaxial epidermis destruction, injury to palisade parenchyma and eventual destruction of more interior tissues after continued exposure to one, six-minute, rain event daily. Results show that most (95%) lesions on Phaseolus vulgaris developed near trichomes and stomata after exposure to the simulated acid rain.

  9. Spatial variability of soil carbon and nitrogen in two hybrid poplar-hay crop systems in southern Quebec, Canada

    Science.gov (United States)

    Winans, K. S.

    2013-12-01

    Canadian agricultural operations contribute approximately 8% of national GHG emissions each year, mainly from fertilizers, enteric fermentation, and manure management (Environment Canada, 2010). With improved management of cropland and forests, it is possible to mitigate GHG emissions through carbon (C) sequestration while enhancing soil and crop productivity. Tree-based intercropped (TBI) systems, consisting of a fast-growing woody species such as poplar (Populus spp.) planted in widely-spaced rows with crops cultivated between tree rows, were one of the technologies prioritized for investigation by the Agreement for the Agricultural Greenhouse Gases Program (AAGGP), because fast growing trees can be a sink for atmospheric carbon-dioxide (CO2) as well as a long-term source of farm income (Montagnini and Nair, 2004). However, there are relatively few estimates of the C sequestration in the trees or due to tree inputs (e.g., fine root turnover, litterfall that gets incorporated into SOC), and hybrid poplars grow exponentially in the first 8-10 years after planting. With the current study, our objectives were (1) to evaluate spatial variation in soil C and nitrogen (N) storage, CO2 and nitrogen oxide (N20), and tree and crop productivity for two hybrid poplar-hay intercrop systems at year 9, comparing TBI vs. non-TBI systems, and (2) to evaluate TBI systems in the current context of C trading markets, which value C sequestration in trees, unharvested crop components, and soils of TBI systems. The study results will provide meaningful measures that indicate changes due to TBI systems in the short-term and in the long-term, in terms of GHG mitigation, enhanced soil and crop productivity, as well as the expected economic returns in TBI systems.

  10. Plant growth regulators in poplar clones differing in resistance to the fungus Ceratocystis fimbriata Ell. et Haist

    Directory of Open Access Journals (Sweden)

    Jadwiga Stopińska

    2014-02-01

    Full Text Available In poplar clones with different resistance to the fungus Ceratocystis fimbriata growth of shoots, intensity of transpiration and the level of endogenous growth regulators were determined. More resistant clones, Populus 'Robusta' and P. 'PK-136-2' (P. nigra 'Italica': x P. laurifolia had more intensive growth of shoots, higher water content in leaves and a lower intensity of transpiration than the more susceptible clone, - P. 'NE-42' (P. maximowiczi x P. trichocarpa. The leaves of the more resistant clones contained more auxins (IAA and cytokinins, especially zeatin, and less growth inhibitors (ABA than those of the susceptible one. The level of plant growth regulators and/or the relations betweeen them may be responsible for the different poplar resistance to C. fimbriata.

  11. Effects of root pruning on the growth and rhizosphere soil characteristics of short-rotation closed-canopy poplar

    Energy Technology Data Exchange (ETDEWEB)

    Du, Z. Y.; Xing, S. J.; Ma, B. Y.; Liu, F. C.; Ma, H. L.; Wang, Q. H.

    2012-11-01

    When poplar trees planted at a high density are canopy-closed in plantation after 4-5 years of growth, the roots of adjacent trees will inevitably intermingle together, which possibly restricts the nutrient uptake by root system. Root pruning might stimulate the emergence of fine roots and benefit the tree growth of short-rotation poplar at the stage of canopy closing. The aim of this study is to evaluate the effects of root pruning on DBH (diameter at breast height, 1.3 m), tree height, nutrients (N, P and K) and hormones (indoleacetic acid and cytokinin) in poplar leaves, gas exchange variables (photosynthetic rate and stomatal conductance), and rhizosphere soil characteristics. Field experiment was carried out with four-yearold poplar (Populus × euramericana cv. ‘Neva’) planted in a fluvo-aquic loam soil in Shandong province, China in early April, 2008. Three root pruning treatments (severe, moderate and light degree) were conducted at the distances of 6, 8 and 10 times DBH on both inter-row sides of the trees to the depth of 30 cm, respectively. The results showed that the growth performance was obtained in the following order of treatments: moderate > light = control > severe. In the rhizophere soil, moderate and light pruning increased the microbial populations, enzymatic activities, and the concentrations of available N, P, K and organic matter. Generally, root pruning to improve tree growth and rhizosphere soil fertility can be recommended in canopy-closed poplar plantation. The appropriate selection of root pruning intensity is a pivotal factor for the effectiveness of this technique. (Author) 35 refs.

  12. Specific gravity of hybrid poplars in the north-central region, USA: within-tree variability and site × genotype effects

    Science.gov (United States)

    William L. Headlee; Ronald S. Jr. Zalesny; Richard B. Hall; Edmund O. Bauer; Bradford Bender; Bruce A. Birr; Raymond O. Miller; Jesse A. Randall; Adam H. Wiese

    2013-01-01

    Specific gravity is an important consideration for traditional uses of hybrid poplars for pulp and solid wood products, as well as for biofuels and bioenergy production. While specific gravity has been shown to be under strong genetic control and subject to within-tree variability, the role of genotype × environment interactions is poorly understood. Most...

  13. Evaluation of two hybrid poplar clones as constructed wetland plant species for treating saline water high in boron and selenium, or waters only high in boron

    Science.gov (United States)

    Wetland mesocosms were constructed to assess two salt- and B-tolerant hybrid poplar clones (Populus trichocarpa ×P. deltoides×P. nigra '345-1' and '347-14') for treating saline water high in boron (B) and selenium (Se). In addition, a hydroponic experiment was performed to test the B tolerance and B...

  14. Organosolv ethanol lignin from hybrid poplar as a radical scavenger: relationship between lignin structure, extraction conditions, and antioxidant activity.

    Science.gov (United States)

    Pan, Xuejun; Kadla, John F; Ehara, Katsunobu; Gilkes, Neil; Saddler, Jack N

    2006-08-09

    Twenty-one organosolv ethanol lignin samples were prepared from hybrid poplar (Populus nigra xP. maximowiczii) under varied conditions with an experimental matrix designed using response surface methodology (RSM). The lignin preparations were evaluated as potential antioxidants. Results indicated that the lignins with more phenolic hydroxyl groups, less aliphatic hydroxyl groups, low molecular weight, and narrow polydispersity showed high antioxidant activity. Processing conditions affected the functional groups and molecular weight of the extracted organosolv ethanol lignins, and consequently influenced the antioxidant activity of the lignins. In general, the lignins prepared at elevated temperature, longer reaction time, increased catalyst, and diluted ethanol showed high antioxidant activity. Regression models were developed to enable the quantitative prediction of lignin characteristics and antioxidant activity based on the processing conditions.

  15. Growth, Gas Exchange, Abscisic Acid, and Calmodulin Response to Salt Stress in Three Poplars

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In the present study, we investigated the effects of increasing salinity on growth, gas exchange, abscisic acid(ABA), calmodulin (CAM), and the relevance to salt tolerance in seedlings of Populus euphratica Oliv. and cuttings of P. "pupularis 35-44" (P. popularis) and P. x euramericana cv. 1-214 (P. cv. Italica). The relative growth rates of shoot height (RGRH) for P. cv. Italica and P. popularis were severely reduced by increasing salt stress,whereas the growth reduction was relatively less in P. euphratica. Similarly, P. euphratica maintained higher net photosynthetic rates (Pn) and unit transpiration rates (TRN) than P. cv. Italica and P. popularis under conditions of higher salinity. Salinity caused a significant increase in leaf ABA and CaM in the three genotypes after the onset of stress, but NaCl-induced ABA and CaM accumulation was more pronounced in P. euphratica,suggesting that P. euphratica plants are more sensitive in sensing soil salinity than the other two poplars.Furthermore, P. euphratica maintained relatively higher ABA and CaM concentrations under conditions of high salinity. The higher capacity to synthesize stress signals, namely ABA and CaM, in P. euphratica and the contribution of this to the salt resistance of P. euphratica are discussed.

  16. Developing xylem-preferential expression of PdGA20ox1, a gibberellin 20-oxidase 1 from Pinus densiflora, improves woody biomass production in a hybrid poplar.

    Science.gov (United States)

    Jeon, Hyung-Woo; Cho, Jin-Seong; Park, Eung-Jun; Han, Kyung-Hwan; Choi, Young-Im; Ko, Jae-Heung

    2016-04-01

    Woody biomass has gained popularity as an environmentally friendly, renewable and sustainable resource for liquid fuel production. Here, we demonstrate biotechnological improvement of the quantity and quality of woody biomass by employing developing xylem (DX)-preferential production of gibberellin (GA), a phytohormone that positively regulates stem growth. First, for the proof of concept experiment, we produced transgenic Arabidopsis plants expressing GA20-oxidase, a key enzyme in the production of bioactive GAs, from Pinus densiflora (PdGA20ox1) under the control of either a constitutive 35S promoter, designated 35S::PdGA20ox1, or a DX-specific promoter (originated from poplar), designated DX15::PdGA20ox1. As we hypothesized, both transgenic Arabidopsis plants (35S::PdGA20ox1 and DX15::PdGA20ox1) exhibited an accelerated stem growth that resulted in a large increase of biomass, up to 300% compared to wild-type control plants, together with increased secondary wall thickening and elongation of fibre cells. Next, we applied our concept to the production of transgenic poplar trees. Both transgenic poplar trees (35S::PdGA20ox1 and DX15::PdGA20ox1) showed dramatic increases in biomass, up to 300%, with accelerated stem growth and xylem differentiation. Cell wall monosaccharide composition analysis revealed that in both Arabidopsis and poplar, glucose and xylose contents were significantly increased. However, undesirable phenotypes of 35S::PdGA20ox1 poplar, including poor root growth and leaf development, were found. Interestingly, DX15::PdGA20ox1 poplar resulted in a reduction of undesirable phenotypes. Our results indicate that the controlled production of GAs through a tissue-specific promoter can be utilized as an efficient biotechnological tool for producing enhanced plant biomass, minimizing unwanted effects.

  17. Tree and stand water fluxes of hybrid poplar clone (Populus nigra x P. maximowiczii) in short rotation coppice culture

    Science.gov (United States)

    Fischer, M.; Trnka, M.; Kucera, J.; Zalud, Z.

    2010-09-01

    This study reports on evapotranspiration and tree water use in short rotation coppice culture of hybrid poplar (Populus nigra x P. maximowiczii) for biomass energy in the Czech Republic. The high density poplar plantation (10 000 trees per ha) was established in 2003 on arable land in Czech-Moravian Highland (49°32´ N, 16°15´ E, 530 m a.s.l.) and has been coppiced in rotation period of 7 years. Firstly, evapotranspiration of the stand has been estimated by applying the Bowen ratio-energy budget method, which is considered as reliable, robust, quite simple and inexpensive technique with comparable results to eddy covariance and lysimeters. The gaps in evapotranspiration diurnal patterns caused by limitation of the bowen ratio method were filled with simple linear regression model based on relation between potential and actual evapotranspiration with regard to soil water availability and leaf area index and thus the daily, monthly and seasonal totals could be calculated. The amount of evapotranspiration during the growing season 2009 (1 March - 31 October) was 593 mm with highest monthly total 116 mm in June. Mean daily water loss over the season reached 2.43 mm per day. During the hot summer day, the maximal value 5.73 mm per day, which presented 89 % of potential evapotranspiration calculated by Penman equation, was recorded with a peak rate 0.94 mm per hour. Secondly, the transpiration was measured by sap flow tissue heat balance techniques on four individual trees with greatest stem diameters (11 - 12 cm d.b.h.) and height of 12 - 12.5 m. Relatively high transpiration values by the poplars were found during the measured part of growing season (18 June - 31 October), with maximum and mean daily transpiration of 44.41 dm3 and 16.69 dm3 per day, respectively. The seasonal transpiration of the most vigorous from the investigated individuals amounted 2542 dm3. Because in this study we didńt evaluate the transpiration of thinner trees (technical features of sap

  18. Effectiveness of mycorrhizal inoculation in the nursery on root colonization, growth, and nutrient uptake of aspen and balsam poplar

    Energy Technology Data Exchange (ETDEWEB)

    Quoreshi, A.M.; Khasa, D.P. [Symbiotech Research Inc. 201, 509-11 Avenue, Nisku, AB (Canada); Forest Biology Research Centre, University of Laval, Quebec (Canada)

    2008-05-15

    Aspen and balsam poplar seedlings were inoculated with six species of ectomycorrhizal fungi (Hebeloma longicaudum, Laccaria bicolor, Paxillus involutus, Pisolithus tinctorius, Rhizopogon vinicolor, and Suillus tomentosus), one species of endomycorrhizal fungus (Glomus intraradices), two species of bacteria (Agrobacterium sp. and Burkholderia cepacia), treated with a growth hormone (SR3), and co-inoculated with a combination of Paxillus and Burkholderia. The seedlings were grown in a greenhouse under three different fertility regimes. Bacterial inoculation alone did not affect seedling growth and nutrition as observed when co-inoculated with ectomycorrhizal fungus. The biomass and root collar diameter of aspen and balsam poplar were significantly increased when adequate mycorrhizas are formed and more prominent when co-inoculated with P. involutus and B. cepacia and grown at the 67% fertilizer level. Except for R. vinicolor and S. tomentosus, the other four species of ectomycorrhizal fungi and G. intraradices formed symbiotic associations with both plant species. Both ectomycorrhizal and endomycorrhizal colonization were observed at all fertilizer levels and fertilizer applications did not affect the colonization rates. Nitrogen and phosphorus concentrations were significantly improved in both aspen and balsam poplar compared with control only when co-inoculated with P. involutus and B. cepacia. However, plant net nitrogen uptake (content) increased significantly in all successful inoculation treatments and co-inoculated treatment when compared with control. These results hold promise for incorporation of inoculation of Populus sp. with appropriate mycorrhizal fungi and selected bacteria into commercial nursery system to improve the establishment of Populus in various sites. (author)

  19. Chemical responses to modified lignin composition in tension wood of hybrid poplar (Populus tremula x Populus alba).

    Science.gov (United States)

    Al-Haddad, Jameel M; Kang, Kyu-Young; Mansfield, Shawn D; Telewski, Frank W

    2013-04-01

    The effect of altering the expression level of the F5H gene was investigated in three wood tissues (normal, opposite and tension wood) in 1-year-old hybrid poplar clone 717 (Populus tremula × Populus alba L.), containing the F5H gene under the control of the C4H promoter. Elevated expression of the F5H gene in poplar has been previously reported to increase the percent syringyl content of lignin. The wild-type and three transgenic lines were inclined 45° for 3 months to induce tension wood formation. Tension and opposite wood from inclined trees, along with normal wood from control trees, were analyzed separately for carbohydrates, lignin, cellulose crystallinity and microfibril angle (MFA). In the wild-type poplar, the lignin in tension wood contained a significantly higher percentage of syringyl than normal wood or opposite wood. However, there was no significant difference in the percent syringyl content of the three wood types within each of the transgenic lines. Increasing the F5H gene expression caused an increase in the percent syringyl content and a slight decrease in the total lignin in normal wood. In tension wood, the addition of a gelatinous layer in the fiber walls resulted in a consistently lower percentage of total lignin in the tissue. Acid-soluble lignin was observed to increase by up to 2.3-fold in the transgenic lines. Compared with normal wood and opposite wood, cell wall crystallinity in tension wood was higher and the MFA was smaller, as expected, with no evidence of an effect from modifying the syringyl monomer ratio. Tension wood in all the lines contained consistently higher total sugar and glucose percentages when compared with normal wood within the respective lines. However, both sugar and glucose percentages were lower in the tension wood of transgenic lines when compared with the tension wood of wild-type trees. Evaluating the response of trees with altered syringyl content to gravity will improve our understanding of the changes

  20. Overexpression of gibberellin 20-oxidase1 from Pinus densiflora results in enhanced wood formation with gelatinous fiber development in a transgenic hybrid poplar.

    Science.gov (United States)

    Park, Eung-Jun; Kim, Hyun-Tae; Choi, Young-Im; Lee, Chanhui; Nguyen, Van Phap; Jeon, Hyung-Woo; Cho, Jin-Seong; Funada, Ryo; Pharis, Richard P; Kurepin, Leonid V; Ko, Jae-Heung

    2015-11-01

    Gibberellins (GAs) are important regulators of plant shoot biomass growth, and GA 20-oxidase (GA20ox) is one of the major regulatory enzymes in the GA biosynthetic pathway. Previously, we showed that the expression levels of a putative GA20ox1 (i.e., PdGA20ox1) in stem tissue of 3-month-old seedlings of 12 families of Pinus densiflora were positively correlated with stem diameter growth across those same families growing in an even-aged 32-year-old pine forest (Park EJ, Lee WY, Kurepin LV, Zhang R, Janzen L, Pharis RP (2015) Plant hormone-assisted early family selection in Pinus densiflora via a retrospective approach. Tree Physiol 35:86-94). To further investigate the molecular function of this gene in the stem wood growth of forest trees, we produced transgenic poplar lines expressing PdGA20ox1 under the control of the 35S promoter (designated as 35S::PdGA20ox1). By age 3 months, most of the 35S::PdGA20ox1 poplar trees were showing an exceptional enhancement of stem wood growth, i.e., up to fourfold increases in stem dry weight, compared with the nontransformed control poplar plants. Significant increases in endogenous GA1, its immediate precursor (GA20) and its catabolite (GA8) in elongating internode tissue accompanied the increased stem growth in the transgenic lines. Additionally, the development of gelatinous fibers occurred in vertically grown stems of the 35S::PdGA20ox1 poplars. An analysis of the cell wall monosaccharide composition of the 35S::PdGA20ox1 poplars showed significant increases in xylose and glucose contents, indicating a qualitative increase in secondary wall depositions. Microarray analyses led us to find a total of 276 probe sets that were upregulated (using threefold as a threshold) in the stem tissues of 35S::PdGA20ox1 poplars relative to the controls. 'Cell organization or biogenesis'- and 'cell wall'-related genes were overrepresented, including many of genes that are involved in cell wall modification. Several transcriptional

  1. Specific Gravity of Hybrid Poplars in the North-Central Region, USA: Within-Tree Variability and Site × Genotype Effects

    Directory of Open Access Journals (Sweden)

    Jesse A. Randall

    2013-04-01

    Full Text Available Specific gravity is an important consideration for traditional uses of hybrid poplars for pulp and solid wood products, as well as for biofuels and bioenergy production. While specific gravity has been shown to be under strong genetic control and subject to within-tree variability, the role of genotype × environment interactions is poorly understood. Most specific gravity reports are for a limited number of locations, resulting in a lack of information about the interactions between clones and sites over a wide range of climate and soil conditions. The objective of the current study was to characterize the effects of bole position, site, clone, and site × clone interactions for twelve hybrid poplar genotypes grown in Iowa, Minnesota, Wisconsin, and Michigan, USA. Observed specific gravities ranged from 0.267 to 0.495 (mean = 0.352 ± 0.001 for 612 samples taken from 204 trees, with bole position and site × clone interactions having significant effects on specific gravity. Further investigation of the site × clone interactions indicated that environmental conditions related to water stress were key predictors of specific gravity. These data are important for informing genotypic selection and silvicultural management decisions associated with growing hybrid poplars.

  2. Mycorrhizae of poplars

    Science.gov (United States)

    R. C. Schultz; J. G. Isebrands; P. P. Kormanik

    1983-01-01

    Poplar hybrids, being screened for short-rotation intensive culture, can form ecto-, endo-, or ectendo-mycorrhizae or may be autotrophic. Different sections of the genus Populus tend to be selective in the type of mycorrhizae formed. Knowledge of which types are formed influences the kinds of propagule production, site preparation, and herbicide...

  3. 741杨生长与木材品质特性%Growth and Wood Property of Poplar 741

    Institute of Scientific and Technical Information of China (English)

    田晓明; 谢进; 屈龙; 刘士畅; 李建梅; 杜洪双; 蒋湘宁; 盖颖

    2013-01-01

    Growth rhythm, cell wall composition, anatomical structure, physical and mechanical properties of poplar 741 were observed and measured. The results showed that, poplar 741 had a long growth period, high growth rate, and plant height, stem diameter and the growth rate of individual volume in growing season had the obvious characteristics of fast-growing. With the scanning electro microscope analysis, we found that fiber cell wall was thin, the shape of its cross section was circular or polygonal, the vessel cells were pitted vessel, wood rays were usually uniseriate; S-lignin content in stem cell wall of poplar 741 was markedly higher than the G-lignin, moreover, with the growing of the poplar 741 , the S-lignin content increased year by year. Basic density of poplar 741 was less than Populus wood, volume shrinkage rate was in a low level, the flexural strength was higher than other kind of Populus wood. According to national standard of impact toughness in wood, the impact toughness of poplar 741 was medium among the main timber tree species. Poplar 741 could be widely applied in green, construction, furniture, plywood, paper and other industries.%对741杨的生长节律、细胞壁化学组成、解剖结构、物理力学性质进行观察和测定.结果表明:741杨生长持续期长,生长速度快,株高、茎粗和单株材积生长量在生长旺季具有速生的特点;在扫描电子显微镜下观察,741杨纤维细胞壁较薄,断面形状多为圆形或多边形,导管多为孔纹型导管,木射线为单列;741杨茎细胞壁中S-木质素含量明显高于G-木质素,随着树龄的增加,S-木质素的含量逐年增加.741杨基本密度小于毛白杨成熟材,体积干缩率在杨属中处于较低水平,抗弯强度与同类型杨树木材相比处于较高水平,冲击韧性按我国主要用材树种冲击韧性大小的分类属中等.741杨可广泛应用于绿化、建筑、家具、胶合板、造纸等行业.

  4. Transformation of spider neurotoxin gene with prospective insecticidal properties into hybrid poplar Populus simonii × P. nigra%向小黑杨转化蜘蛛杀虫毒素基因

    Institute of Scientific and Technical Information of China (English)

    林同; 王志英; 刘宽余; 景天忠; 张传溪

    2006-01-01

    In recent years, the pest insects on hybrid poplar Populus simonii × P. nigra broke out heavily, which caused great losses in forestry. In order to improve insect resistance of P. simonii × P. nigra and avoid pollution due to insecticides, the fused BGT gene consisting of the insecticidal toxin gene from the spider, Atrax robustus, and the C terminal of Cry Ⅰ A (b) gene from Bacillus thuringiensis was transferred into P. simonii × P. nigra by Agrobacteriumm-mediated transformation system. The results of PCR and Southern blotting analyses showed that the insecticidal gene of BGT was integrated into the genome of P. simonii × P. nigra. The corrected mortality of the second instar of Lymantria dispar in 6 days and 9 days after they were fed with the transgenic poplars was 37.0% and92.6% , respectively. Analysis of variance showed that there was significant difference in body weight between L. dispar larvae fed with the transformed poplars and those fed with untransformed poplars. The results indicated that the growth rate of L. dispar fed with the transgenic poplars was affected negatively.%近年来,危害小黑杨Populus simonii×P.nigra的害虫发生严重,给林业生产造成很大损失.为了提高小黑杨的抗虫能力,避免使用杀虫剂带来的污染,用农杆菌介导法将澳大利亚漏斗蛛Atrax robustus的毒蛋白基因和苏云金芽孢杆菌Cry Ⅰ A(b)基因C末端的融合基因BGT转化入小黑杨.PCR和Southern印记分析转基因植株,结果表明,BGT杀虫基因已经整合在小黑杨基因组上.活性实验表明,取食转基因杨树6天和9天后,舞毒蛾Lymantria dispar 2龄幼虫的校正死亡率分别是37.0%和92.6%.方差分析表明取食转基因和对照杨树的舞毒蛾幼虫体重差异显著.这些结果显示转基因杨树上的舞毒蛾的发育速率受到影响.

  5. Biomass carbon, nitrogen and phosphorus stocks in hybrid poplar buffers, herbaceous buffers and natural woodlots in the riparian zone on agricultural land.

    Science.gov (United States)

    Fortier, Julien; Truax, Benoit; Gagnon, Daniel; Lambert, France

    2015-05-01

    In many temperate agricultural areas, riparian forests have been converted to cultivated land, and only narrow strips of herbaceous vegetation now buffer many farm streams. The afforestation of these riparian zones has the potential to increase carbon (C) storage in agricultural landscapes by creating a new biomass sink for atmospheric CO2. Occurring at the same time, the storage of nitrogen (N) and phosphorus (P) in plant biomass, is an important water quality function that may greatly vary with types of riparian vegetation. The objectives of this study were (1) to compare C, N and P storage in aboveground, belowground and detrital biomass for three types of riparian vegetation cover (9-year-old hybrid poplar buffers, herbaceous buffers and natural woodlots) across four agricultural sites and (2) to determine potential vegetation cover effects on soil nutrient supply rate in the riparian zone. Site level comparisons suggest that 9-year-old poplar buffers have stored 9-31 times more biomass C, 4-10 times more biomass N, and 3-7 times more biomass P than adjacent non managed herbaceous buffers, with the largest differences observed on the more fertile sites. The conversion of these herbaceous buffers to poplar buffers could respectively increase C, N and P storage in biomass by 3.2-11.9 t/ha/yr, 32-124 kg/ha/yr and 3.2-15.6 kg/ha/yr, over 9 years. Soil NO3 and P supply rates during the summer were respectively 57% and 66% lower in poplar buffers than in adjacent herbaceous buffers, potentially reflecting differences in nutrient storage and cycling between the two buffer types. Biomass C ranged 49-160 t/ha in woodlots, 33-110 t/ha in poplar buffers and 3-4 t/ha in herbaceous buffers. Similar biomass C stocks were found in the most productive poplar buffer and three of the four woodlots studied. Given their large and varied biomass C stocks, conservation of older riparian woodlots is equally important for C balance management in farmland. In addition, the

  6. Overexpression of PtrMYB119, a R2R3-MYB transcription factor from Populus trichocarpa, promotes anthocyanin production in hybrid poplar.

    Science.gov (United States)

    Cho, Jin-Seong; Nguyen, Van Phap; Jeon, Hyung-Woo; Kim, Min-Ha; Eom, Seok Hyun; Lim, You Jin; Kim, Won-Chan; Park, Eung-Jun; Choi, Young-Im; Ko, Jae-Heung

    2016-09-01

    Anthocyanins are a group of colorful and bioactive natural pigments with important physiological and ecological functions in plants. We found an MYB transcription factor (PtrMYB119) from Populus trichocarpa that positively regulates anthocyanin production when expressed under the control of the CaMV 35S promoter in transgenic Arabidopsis Amino acid sequence analysis revealed that PtrMYB119 is highly homologous to Arabidopsis PAP1 (PRODUCTION OF ANTHOCYANIN PIGMENT1), a well-known transcriptional activator of anthocyanin biosynthesis. Independently produced transgenic poplars overexpressing PtrMYB119 or PtrMYB120 (a paralogous gene to PtrMYB119) (i.e., 35S::PtrMYB119 and 35S::PtrMYB120, respectively) showed elevated accumulation of anthocyanins in the whole plants, including leaf, stem and even root tissues. Using a reverse-phase high-performance liquid chromatography, we confirmed that the majority of the accumulated anthocyanin in our transgenic poplar is cyanidin-3-O-glucoside. Gene expression analyses revealed that most of the genes involved in the anthocyanin biosynthetic pathway were highly upregulated in 35S::PtrMYB119 poplars compared with the nontransformed control poplar. Among these genes, expression of PtrCHS1 (Chalcone Synthase1) and PtrANS2 (Anthocyanin Synthase2), which catalyze the initial and last steps of anthocyanin biosynthesis, respectively, was upregulated by up to 350-fold. Subsequent transient activation assays confirmed that PtrMYB119 activated the transcription of both PtrCHS1 and PtrANS2 Interestingly, expression of MYB182, a repressor of both anthocyanin and proanthocyanidin (PA) biosynthesis, was largely suppressed in 35S::PtrMYB119 poplars, while expression of MYB134, an activator of PA biosynthesis, was not changed significantly. More interestingly, high-level accumulation of anthocyanins in 35S::PtrMYB119 poplars did not have an adverse effect on plant growth. Taken together, our results demonstrate that PtrMYB119 and PtrMYB120

  7. Effect of poultry litter biochar on Saccharomyces cerevisiae growth and ethanol production from steam-exploded poplar and corn stover

    Science.gov (United States)

    Diallo, Oumou

    The use of ethanol produced from lignocellulosic biomass for transportation fuel offers solutions in reducing environmental emission and the use of non-renewable fuels. However, lignocellulosic ethanol production is still hampered by economic and technical obstacles. For instance, the inhibitory effect of toxic compounds produced during biomass pretreatment was reported to inhibit the fermenting microorganisms, hence there was a decrease in ethanol yield and productivity. Thus, there is a need to improve the bioconversion of lignocellulosic biomass to ethanol in order to promote its commercialization. The research reported here investigated the use of poultry litter biochar to improve the ethanol production from steam-exploded poplar and corn stover. The effect of poultry litter biochar was first studied on Saccharomyces cerevisiae ATCC 204508/S288C growth, and second on the enzyme hydrolysis and fermentation of two steam-exploded biomasses: (poplar and corn stover). The third part of the study investigated optimal process parameters (biochar loading, biomass loading, and enzyme loading) on the reducing sugars production, and ethanol yield from steam-exploded corn stover. In this study, it has been shown that poultry litter biochar improved the S. cerevisiae growth and ethanol productivity; therefore poultry litter biochar could potentially be used to improve the ethanol production from steam-exploded lignocellulosic biomass.

  8. Isolation and identification of phytate-degrading rhizobacteria with activity of improving growth of poplar and Masson pine.

    Science.gov (United States)

    Li, Gui-E; Wu, Xiao-Qin; Ye, Jian-Ren; Hou, Liang; Zhou, Ai-Dong; Zhao, Liu

    2013-11-01

    A number of soil microorganisms can convert insoluble forms of phosphorus (P) to an accessible form to increase plant yields. Phytate is such a large kind of insoluble organic phosphorus that plants cannot absorb directly in soil, so the objectives of this study were to isolate, screen phytate-degrading rhizobacteria (PDRB), and to select potential microbial inocula that could increase the P uptake by plants. In this study, a total of 24 soil samples were collected from natural habitats of eight poplar and pine planting areas from the eastern to southern China. 17 PDRB strains were preliminarily screened from the rhizosphere soil of poplars and pines by the visible decolorization in the phytate selective medium. The highest ratio of the total diameter (colony + halo zone) to the colony diameter of the isolates was JZ-GX1, 3.85. Afterward, 17 PDRB strains were further determined for their abilities to degrade sodium phytate based on the amount of liberated inorganic P in liquid phytate specific medium. The results showed that the phytase ability of the three highest PDRB strains: JZ-GX1, JZ-DZ1 and JZ-ZJ1 were up to 2.58, 2.36 and 2.24 U/mL, respectively, much better than most of the bacteria reported in previous studies. In the soil-plant experiment, compared to CK, the best three strains of PDRB all could significantly promote growth of poplar and Masson pine under container growing. The three efficient PDRB strains were identified as follow: JZ-GX1, Rahnella aquatilis, both JZ-DZ1 and JZ-ZJ1 being autofluorescent, Pseudomonas fluorescens, by 16S rDNA gene sequencing technology, Biolog Identification System and biological characterization. The present study suggests that the three screened PDRB strains would have great potential application as biological fertilizers in the future.

  9. Transcriptome profiles of hybrid poplar (Populus trichocarpa × deltoides) reveal rapid changes in undamaged, systemic sink leaves after simulated feeding by forest tent caterpillar (Malacosoma disstria).

    Science.gov (United States)

    Philippe, Ryan N; Ralph, Steven G; Mansfield, Shawn D; Bohlmann, Jörg

    2010-11-01

    Poplar has been established as a model tree system for genomic research of the response to biotic stresses. This study describes a series of induced transcriptome changes and the associated physiological characterization of local and systemic responses in hybrid poplar (Populus trichocarpa × deltoides) after simulated herbivory. • Responses were measured in local source (LSo), systemic source (SSo), and systemic sink (SSi) leaves following application of forest tent caterpillar (Malacosoma disstria) oral secretions to mechanically wounded leaves. • Transcriptome analyses identified spatially and temporally dynamic, distinct patterns of local and systemic gene expression in LSo, SSo and SSi leaves. Galactinol synthase was strongly and rapidly upregulated in SSi leaves. Genome analyses and full-length cDNA cloning established an inventory of poplar galactinol synthases. Induced changes of galactinol and raffinose oligosaccharides were detected by anion-exchange high-pressure liquid chromatography. • The LSo leaves showed a rapid and strong transcriptome response compared with a weaker and slower response in adjacent SSo leaves. Surprisingly, the transcriptome response in distant, juvenile SSi leaves was faster and stronger than that observed in SSo leaves. Systemic transcriptome changes of SSi leaves have signatures of rapid change of metabolism and signaling, followed by later induction of defense genes.

  10. Short and mid-term effects of artificial defoliation on the growth of euramerican poplar (Populus × canadensis clone I-214 in poplar stands in relation to the intensity and seasonal timing of defoliation.

    Directory of Open Access Journals (Sweden)

    Allegro G

    2017-08-01

    Full Text Available The impact of artificial defoliations on the growth of euramerican poplar (Populus × canadensis clone I-214 was investigated in three field assays. Young poplar trees (1st-3rd cultivation year were subjected to 25%, 50%, 75% and 100% defoliation either in the early or in the late growing season (or in both periods, and their growth was measured in the same year and during the following 2-3 years. Only trees treated to 75% and 100% defoliation exhibited a significant growth decrease compared to control trees: the diametric growth of early defoliated trees was reduced up to 20-40% in the year of defoliation, whereas trees defoliated at the same rates late in the season, or defoliated twice in a single year, suffered the heaviest damage, showing a growth loss up to 50% in the year following the defoliation events. In the latter cases, a delayed sprouting at spring and the death of branchlets were observed. A financial analysis showed that the economic damage caused by the highest defoliation rates, mainly when occurring late in the season, definitely exceeds the cost of treatments, thus suggesting the adoption of appropriate control strategies.

  11. Plant growth promotion, metabolite production and metal tolerance of dark septate endophytes isolated from metal-polluted poplar phytomanagement sites.

    Science.gov (United States)

    Berthelot, Charlotte; Leyval, Corinne; Foulon, Julie; Chalot, Michel; Blaudez, Damien

    2016-10-01

    Numerous studies address the distribution and the diversity of dark septate endophytes (DSEs) in the literature, but little is known about their ecological role and their effect on host plants, especially in metal-polluted soils. Seven DSE strains belonging to Cadophora, Leptodontidium, Phialophora and Phialocephala were isolated from roots of poplar trees from metal-polluted sites. All strains developed on a wide range of carbohydrates, including cell-wall-related compounds. The strains evenly colonized birch, eucalyptus and ryegrass roots in re-synthesis experiments. Root and shoot growth promotion was observed and was both plant and strain dependent. Two Phialophora and Leptodontidium strains particularly improved plant growth. However, there was no correlation between the level of root colonization by DSEs and the intensity of growth promotion. All strains produced auxin and six also stimulated plant growth through the release of volatile organic compounds (VOCs). SPME-GC/MS analyses revealed four major VOCs emitted by Cadophora and Leptodontidium The strains exhibited growth at high concentrations of several metals. The ability of metal-resistant DSE strains to produce both soluble and volatile compounds for plant growth promotion indicates interesting microbial resources with high potential to support sustainable production of bioenergy crops within the context of the phytomanagement of metal-contaminated sites.

  12. Characterization of hemizygous deletions in citrus using array-comparative genomic hybridization and microsynteny comparisons with the poplar genome.

    Science.gov (United States)

    Ríos, Gabino; Naranjo, Miguel A; Iglesias, Domingo J; Ruiz-Rivero, Omar; Geraud, Marion; Usach, Antonio; Talón, Manuel

    2008-08-09

    Many fruit-tree species, including relevant Citrus spp varieties exhibit a reproductive biology that impairs breeding and strongly constrains genetic improvements. In citrus, juvenility increases the generation time while sexual sterility, inbreeding depression and self-incompatibility prevent the production of homozygous cultivars. Genomic technology may provide citrus researchers with a new set of tools to address these various restrictions. In this work, we report a valuable genomics-based protocol for the structural analysis of deletion mutations on an heterozygous background. Two independent fast neutron mutants of self-incompatible clementine (Citrus clementina Hort. Ex Tan. cv. Clemenules) were the subject of the study. Both mutants, named 39B3 and 39E7, were expected to carry DNA deletions in hemizygous dosage. Array-based Comparative Genomic Hybridization (array-CGH) using a Citrus cDNA microarray allowed the identification of underrepresented genes in these two mutants. Subsequent comparison of citrus deleted genes with annotated plant genomes, especially poplar, made possible to predict the presence of a large deletion in 39B3 of about 700 kb and at least two deletions of approximately 100 and 500 kb in 39E7. The deletion in 39B3 was further characterized by PCR on available Citrus BACs, which helped us to build a partial physical map of the deletion. Among the deleted genes, ClpC-like gene coding for a putative subunit of a multifunctional chloroplastic protease involved in the regulation of chlorophyll b synthesis was directly related to the mutated phenotype since the mutant showed a reduced chlorophyll a/b ratio in green tissues. In this work, we report the use of array-CGH for the successful identification of genes included in a hemizygous deletion induced by fast neutron irradiation on Citrus clementina. The study of gene content and order into the 39B3 deletion also led to the unexpected conclusion that microsynteny and local gene colinearity in

  13. Characterization of hemizygous deletions in Citrus using array-Comparative Genomic Hybridization and microsynteny comparisons with the poplar genome

    Directory of Open Access Journals (Sweden)

    Usach Antonio

    2008-08-01

    Full Text Available Abstract Background Many fruit-tree species, including relevant Citrus spp varieties exhibit a reproductive biology that impairs breeding and strongly constrains genetic improvements. In citrus, juvenility increases the generation time while sexual sterility, inbreeding depression and self-incompatibility prevent the production of homozygous cultivars. Genomic technology may provide citrus researchers with a new set of tools to address these various restrictions. In this work, we report a valuable genomics-based protocol for the structural analysis of deletion mutations on an heterozygous background. Results Two independent fast neutron mutants of self-incompatible clementine (Citrus clementina Hort. Ex Tan. cv. Clemenules were the subject of the study. Both mutants, named 39B3 and 39E7, were expected to carry DNA deletions in hemizygous dosage. Array-based Comparative Genomic Hybridization (array-CGH using a Citrus cDNA microarray allowed the identification of underrepresented genes in these two mutants. Subsequent comparison of citrus deleted genes with annotated plant genomes, especially poplar, made possible to predict the presence of a large deletion in 39B3 of about 700 kb and at least two deletions of approximately 100 and 500 kb in 39E7. The deletion in 39B3 was further characterized by PCR on available Citrus BACs, which helped us to build a partial physical map of the deletion. Among the deleted genes, ClpC-like gene coding for a putative subunit of a multifunctional chloroplastic protease involved in the regulation of chlorophyll b synthesis was directly related to the mutated phenotype since the mutant showed a reduced chlorophyll a/b ratio in green tissues. Conclusion In this work, we report the use of array-CGH for the successful identification of genes included in a hemizygous deletion induced by fast neutron irradiation on Citrus clementina. The study of gene content and order into the 39B3 deletion also led to the unexpected

  14. The poplar Rust-Induced Secreted Protein (RISP inhibits the growth of the leaf rust pathogen Melampsora larici-populina and triggers cell culture alkalinisation

    Directory of Open Access Journals (Sweden)

    Benjamin ePetre

    2016-02-01

    Full Text Available Plant cells secrete a wide range of proteins in extracellular spaces in response to pathogen attack. The poplar Rust-Induced Secreted Protein (RISP is a small cationic protein of unknown function that was identified as the most induced gene in poplar leaves during immune responses to the leaf rust pathogen Melampsora larici-populina, an obligate biotrophic parasite. Here, we combined in planta and in vitro molecular biology approaches to tackle the function of RISP. Using a RISP-mCherry fusion transiently expressed in Nicotiana benthamiana leaves, we demonstrated that RISP is secreted into the apoplast. A recombinant RISP specifically binds to M. larici-populina urediniospores and inhibits their germination. It also arrests the growth of the fungus in vitro and on poplar leaves. Interestingly, RISP also triggers poplar cell culture alkalinisation and is cleaved at the C-terminus by a plant-encoded mechanism. Altogether our results indicate that RISP is an antifungal protein that has the ability to trigger cellular responses.

  15. The Poplar Rust-Induced Secreted Protein (RISP) Inhibits the Growth of the Leaf Rust Pathogen Melampsora larici-populina and Triggers Cell Culture Alkalinisation.

    Science.gov (United States)

    Petre, Benjamin; Hecker, Arnaud; Germain, Hugo; Tsan, Pascale; Sklenar, Jan; Pelletier, Gervais; Séguin, Armand; Duplessis, Sébastien; Rouhier, Nicolas

    2016-01-01

    Plant cells secrete a wide range of proteins in extracellular spaces in response to pathogen attack. The poplar rust-induced secreted protein (RISP) is a small cationic protein of unknown function that was identified as the most induced gene in poplar leaves during immune responses to the leaf rust pathogen Melampsora larici-populina, an obligate biotrophic parasite. Here, we combined in planta and in vitro molecular biology approaches to tackle the function of RISP. Using a RISP-mCherry fusion transiently expressed in Nicotiana benthamiana leaves, we demonstrated that RISP is secreted into the apoplast. A recombinant RISP specifically binds to M. larici-populina urediniospores and inhibits their germination. It also arrests the growth of the fungus in vitro and on poplar leaves. Interestingly, RISP also triggers poplar cell culture alkalinisation and is cleaved at the C-terminus by a plant-encoded mechanism. Altogether our results indicate that RISP is an antifungal protein that has the ability to trigger cellular responses.

  16. Elevated CO2 concentration, fertilization and their interaction: growth stimulation in a short-rotation poplar coppice (EUROFACE).

    Science.gov (United States)

    Liberloo, Marion; Dillen, Sophie Y; Calfapietra, Carlo; Marinari, Sara; Luo, Zhi Bin; De Angelis, Paolo; Ceulemans, Reinhart

    2005-02-01

    We investigated the individual and combined effects of elevated CO2 concentration and fertilization on aboveground growth of three poplar species (Populus alba L. Clone 2AS-11, P. nigra L. Clone Jean Pourtet and P. x euramericana Clone I-214) growing in a short-rotation coppice culture for two growing seasons after coppicing. Free-air carbon dioxide enrichment (FACE) stimulated the number of shoots per stool, leaf area index measured with a fish-eye-type plant canopy analyzer (LAIoptical), and annual leaf production, but did not affect dominant shoot height or canopy productivity index. Comparison of LAIoptical with LAI estimates from litter collections and from allometric relationships showed considerable differences. The increase in biomass in response to FACE was caused by an initial stimulation of absolute and relative growth rates, which disappeared after the first growing season following coppicing. An ontogenetic decline in growth in the FACE treatment, together with strong competition inside the dense plantation, may have caused this decrease. Fertilization did not influence aboveground growth, although some FACE responses were more pronounced in fertilized trees. A species effect was observed for most parameters.

  17. The poplar basic helix-loop-helix transcription factor BEE3 – Like gene affects biomass production by enhancing proliferation of xylem cells in poplar

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Seol Ah, E-mail: s6022029@korea.ac.kr; Choi, Young-Im, E-mail: yichoi99@forest.go.kr; Cho, Jin-Seong, E-mail: jinsung3932@gmail.com; Lee, Hyoshin, E-mail: hslee@forest.go.kr

    2015-06-19

    Brassinosteroids (BRs) play important roles in many aspects of plant growth and development, including regulation of vascular cambium activities and cell elongation. BR-induced BEE3 (brassinosteroid enhanced expression 3) is required for a proper BR response. Here, we identified a poplar (Populus alba × Populus glandulosa) BEE3-like gene, PagBEE3L, encoding a putative basic helix-loop-helix (bHLH)-type transcription factor. Expression of PagBEE3L was induced by brassinolide (BL). Transcripts of PagBEE3L were mainly detected in stems, with the internode having a low level of transcription and the node having a relatively higher level. The function of the PagBEE3L gene was investigated through phenotypic analyses with PagBEE3L-overexpressing (ox) transgenic lines. This work particularly focused on a potential role of PagBEE3L in stem growth and development of polar. The PagBEE3L-ox poplar showed thicker and longer stems than wild-type plants. The xylem cells from the stems of PagBEE3L-ox plants revealed remarkably enhanced proliferation, resulting in an earlier thickening growth than wild-type plants. Therefore, this work suggests that xylem development of poplar is accelerated in PagBEE3L-ox plants and PagBEE3L plays a role in stem growth by increasing the proliferation of xylem cells to promote the initial thickening growth of poplar stems. - Highlights: • We identify the BEE3-like gene form hybrid poplar (Populus alba × Populus glandulosa). • We examine effects of overexpression of PagBEE3L on growth in poplar. • We found that 35S:BEE3L transgenic plants showed more rapid growth than wild-type plants. • BEE3L protein plays an important role in the development of plant stem.

  18. Variation among poplar clones for growth and crown traits under field conditions at two sites of North-western India

    Institute of Scientific and Technical Information of China (English)

    G.P.S.Dhillon; Avtar Singh; D.S.Sidhu; H.S.Brar

    2013-01-01

    We evaluated the growth and crown traits of 36 poplar clones at two distinct agro-climatic regions of Punjab (Ludhiana and Bathinda)in northwestern India,following randomized block design with three replications and plot size of four trees.Significant differences among clones (p<0.001) were observed for diameter at breast height (DBH),tree height,volume,crown width and number of branches under both the site conditions.Clones ‘G-3',‘25-N' and ‘41-N' at Ludhiana and ‘G-3',‘RD-01' and ‘S7C8' at Bathinda were found to be superior for volume production.All growth and crown traits registered significantly higher values at Ludhiana in comparison to those at Bathinda.Clone × site interaction was also significant (p<0.001).For volume,clones ‘L-62/84',‘113520',‘25-N' and ‘S4C2' witnessed huge fluctuations in ranking between sites.The correlations between growth traits were positive and highly significant (p<0.001) at both sites.The clonal mean heritability was moderate for DBH and volume both at Ludhiana (0.61-0.66) and Bathinda (0.61-0.62).Across sites,the genetic advance was the highest for volume (49.76%) and the lowest (6.50%) in case of height.

  19. The low fertility of Chinese white poplar: dynamic changes in anatomical structure, endogenous hormone concentrations, and key gene expression in the reproduction of a naturally occurring hybrid.

    Science.gov (United States)

    Ma, Kaifeng; Song, Yuepeng; Huang, Zhen; Lin, Liyuan; Zhang, Zhiyi; Zhang, Deqiang

    2013-03-01

    KEY MESSAGE : We report that low fertility during intraspecific hybridization in Chinese white poplar was caused by prefertilization barriers, reduced ovules, and embryonic abortion. Hormone concentrations and gene expression patterns were also evaluated during the fertilization process. Hybrid vigor holds tremendous potential for yield increases and trait improvement; however, some hybridization combinations within Populus show very low fertility. To explore the causes of this low fertility in intraspecific hybridization of Chinese white poplar, we examined anatomical structure, hormone levels and expression of key genes in two unique crossing combinations of Populus × tomentosa "Pt02" × P. × tomentosa "LM50", and (P. × tomentosa × P. alba cv. bolleana "Ptb") × P. × tomentosa "LM50". The seed set potential in the intraspecific hybridization P. × tomentosa "Pt02" × P. × tomentosa "LM50" was quite low, which was likely caused by prefertilization barriers, reduced ovule numbers, and embryonic abortion in ovaries. During intraspecific hybridization, we found reduced indoleacetic acid (IAA) in pistils, which may cause pollen tube deformations and increased IAA in heart-stage embryos, which may affect embryo development. Gibberellin A3 (GA3) decreased from the zygote dormancy stage to globular-stage embryos, which may be caused by failure of fertilization in specific embryos. The maximum zeatin (Z) concentration was found in heart-stage embryos, but Z concentrations quickly decreased, which may affect endosperm development. Increasing concentrations of abscisic acid (ABA) during zygote dormancy and eight-cell proembryo stages likely induced abscission of the infructescence. High ABA concentrations also regulated embryo maturity. Measurement of genes expression showed that high expression of SRK and/or SLG may result in rejection of pollen by stigmatic papillae through a mechanism, reminiscent of self-incompatibility. Also, low expression of

  20. Growth and metal accumulation in Porcellio scaber exposed to poplar litter from Cd-, Pb-, and Zn-contaminated sites.

    Science.gov (United States)

    Godet, Jean-Philippe; Demuynck, Sylvain; Waterlot, Christophe; Lemière, Sébastien; Souty-Grosset, Catherine; Scheifler, Renaud; Douay, Francis; Leprêtre, Alain; Pruvot, Christelle

    2011-03-01

    This study aimed at determining, in the laboratory, the effects of poplar litter collected in woody habitats contaminated by heavy metals on growth and metal accumulation in the terrestrial isopod Porcellio scaber. Cd, Pb, and Zn pseudototal and CaCl(2)-extractable concentrations in litter types were determined using AAS. Juveniles were fed ad libitum, individually, for 28 days with four litter types presenting an increasing gradient of metal contamination. Individuals were weighed every week and metal body burdens were determined at the end of the experiment. From the first week until the end of the experiment, a decrease in P. scaber growth related to the increase of metal concentration in litter types was recorded. Significant correlations were observed between metal body burdens and metal concentrations in litter types. However, Cd accumulation in woodlice appeared to be related to the Cd/Zn concentration ratio in litter types. All these results showed the potential of weight gain in P. scaber as a suitable indicator for litter quality assessment with ecological relevance.

  1. Hydroponic screening of poplar for trace element tolerance and accumulation.

    Science.gov (United States)

    Migeon, Aude; Richaud, Pierre; Guinet, Frédéric; Blaudez, Damien; Chalot, Michel

    2012-04-01

    Using the nutrient film technique, we screened 21 clones of poplar for growth in the presence of a mix of trace elements (TE) and for TE accumulation capacities. Poplar cuttings were exposed for four weeks to a multipollution solution consisting in 10 microM Cd, Cu, Ni, and Pb, and 200 microM Zn. Plant biomass and TE accumulation patterns in leaves varied greatly between clones. The highest Cd and Zn concentrations in leaves were detected in P. trichocarpa and P. trichocarpa hybrids, with the clone Skado (P. trichocarpa x P. maximowiczii) accumulating up to 108 mg Cd kg(-1) DW and 1510 mg Zn kg(-1) DW when exposed to a multipollution context. Our data also confirm the importance of pH and multipollution, as these factors greatly affect TE accumulation in above ground biomass. The NFT technique applied here to a large range of poplar clones also revealed the potential of the Rochester, AFO662 and AFO678 poplar clones for use in phytostabilization programs and bioenergy production, where production of less contaminated above ground biomass is suitable.

  2. Comparative study of plant growth of two poplar tree species irrigated with treated wastewater, with particular reference to accumulation of heavy metals (Cd, Pb, As, and Ni).

    Science.gov (United States)

    Houda, Zarati; Bejaoui, Zoubeir; Albouchi, Ali; Gupta, Dharmendra K; Corpas, Francisco J

    2016-02-01

    Water is a scarce natural resource around the world which can hamper the socio-economic development of many countries. The Mediterranean area, especially north Africa, is known for its semi-arid to arid climate, causing serious water supply problems. Treated wastewater (TWW) is being used as an alternative strategy for recycling wastewater. It is also a potential source of nutrients for reforestation with certain plant species such as poplar trees, a useful wood resource, and even for phytoremediation purposes. In the present study, we used treated wastewater to irrigate two clones of 1-year-old poplar trees (Populus nigra cv. I-488 and Populus alba cv. MA-104) for 90 days. After a stipulated time, a comparative study was made of the effects of TWW on growth parameters, acquisition of essential minerals (Na, Fe and Zn) and pollutants (Cd, Pb, As and Ni) as well as the enrichment of secondary metabolites such as polyphenolic, flavonoid and tannin compounds which could contribute to the growth and development of poplar plants. The results of this study show that the use of TWW increased P. alba's biomass production by 36% and also enhanced its Cd and Pb accumulation capacity. We also found that P. alba has considerable potential to be used as an alternative plant species for reforestation and/or phytoremediation of toxic metals from contaminated water or effluent.

  3. Potential of the TCE-degrading endophyte Pseudomonas putida W619-TCE to improve plant growth and reduce TCE phytotoxicity and evapotranspiration in poplar cuttings

    Energy Technology Data Exchange (ETDEWEB)

    Weyens, N.; van der Lelie, D.; Truyens, S.; Dupae, J.; Newman, L.; Taghavi, S.; Carleer, R.; Vangronsveld, J.

    2010-09-01

    The TCE-degrading poplar endophyte Pseudomonas putida W619-TCE was inoculated in poplar cuttings, exposed to 0, 200 and 400 mg l{sup -1} TCE, that were grown in two different experimental setups. During a short-term experiment, plants were grown hydroponically in half strength Hoagland nutrient solution and exposed to TCE for 3 days. Inoculation with P. putida W619-TCE promoted plant growth, reduced TCE phytotoxicity and reduced the amount of TCE present in the leaves. During a mid-term experiment, plants were grown in potting soil and exposed to TCE for 3 weeks. Here, inoculation with P. putida W619-TCE had a less pronounced positive effect on plant growth and TCE phytotoxicity, but resulted in strongly reduced amounts of TCE in leaves and roots of plants exposed to 400 mg l{sup -1} TCE, accompanied by a lowered evapotranspiration of TCE. Dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), which are known intermediates of TCE degradation, were not detected. The endophyte P. putida W619-TCE degrades TCE during its transport through the xylem, leading to reduced TCE concentrations in poplar, and decreased TCE evapotranspiration.

  4. Dinamica şi caracteristicile creşterii a şase clone de plop hibrid pe parcursul unui ciclu de producţie într-o plantație comparativă din Depresiunea Rădăuţi [The dynamics and growth characteristics of six hybrid poplar clones during a production cycle in a comparative plantation from Rădăuți Depression

    OpenAIRE

    Dănilă Iulian; Avăcăriței Daniel; Savin Alexei; Roibu Cătălin Constantin; Bouriaud Olivier; Duduman Mihai-Leonard; Bouriaud Laura

    2015-01-01

    The poplar (Populus spp.) plays an important role in worldwide forest economy, responding to the necessities of obtaining high biomass production in a short time. Short rotation forests (SRF) are developing continuously in Romania. Several studies have been undertaken to identify the clones with high productivity and suitable technologies. The aim of this study was to register the annual increments in diameter, height and volume in an experimental poplar crops with a short-term rotation of...

  5. Comparative Studies on the Growth of Different Poplar Clones on Beach Land of Yangtse River%长江滩地不同杨树无性系的生长比较

    Institute of Scientific and Technical Information of China (English)

    唐罗忠; 吴麟; 葛晓敏; 田野; 囤兴建; 刘东; 方升佐

    2013-01-01

    In order to select the poplar clones suitable to be planted on the beach land of Yangtse River, twenty clones of poplar were cultivated on the beach land in Ma' anshan City, Anhui province, China. The growth, survival rate and lodging situation of each clone were measured three years after planting, and their comprehensive performances were evaluated by improved Analytic Hierarchy Process (AHP). The result showed that the growth (including diameter at breast height, height and volume ) , survival rate, height under the branches and tilt angle were significantly different among these four-year-old poplar clones. The integrated evaluation showed that the comprehensive qualities of poplar clones were significantly different- The integrated values of poplar clone 895, clone 324 and clone 1388 were higher, and the integrated values of clones 447, clone 136 and clone 316 were lower than the others. This indicated that the performances of four-year-old clone 895, clone 324 and clone 1388 were better than that of the other clones, and the three poplar clones could be selected to plant on the beach land of Yangtse River.

  6. Improvement of controlled pollination techniques of poplar

    Institute of Scientific and Technical Information of China (English)

    ZHOU Zhong-cheng; LIU Zong-you; HOU Kai-ju; SUN Xian-meng; ZHANG Ji-he; SHEN Bao-xian

    2008-01-01

    Over a number of years, in order to find substitutes for two traditional poplar pollination techniques: outdoor bridging trees and indoor cutting with water culture, research into two new pollination methods of uprooted outdoor seed trees and outdoor cutting branches was carried out. The advantages of two new and improved techniques were of efficiency, economy, safety and ease of operation. The methods can be applied in hybridization and breeding of poplar and other easy-to-root trees.

  7. Analysis of 4,664 high-quality sequence-finished poplar full-length

    Energy Technology Data Exchange (ETDEWEB)

    Ralph, S. [University of British Columbia, Vancouver; Gunter, Lee E [ORNL; Tuskan, Gerald A [ORNL; Douglas, Carl [University of British Columbia, Vancouver; Holt, Robert A. [Genome Sciences Centre, Vancouver, BC, Canada; Jones, Steven [Genome Sciences Centre, Vancouver, BC, Canada; Marra, Marco [Genome Sciences Centre, Vancouver, BC, Canada; Bohlmann, J. [University of British Columbia, Vancouver

    2008-01-01

    The genus Populus includes poplars, aspens and cottonwoods, which will be collectively referred to as poplars hereafter unless otherwise specified. Poplars are the dominant tree species in many forest ecosystems in the Northern Hemisphere and are of substantial economic value in plantation forestry. Poplar has been established as a model system for genomics studies of growth, development, and adaptation of woody perennial plants including secondary xylem formation, dormancy, adaptation to local environments, and biotic interactions. As part of the poplar genome sequencing project and the development of genomic resources for poplar, we have generated a full-length (FL)-cDNA collection using the biotinylated CAP trapper method. We constructed four FLcDNA libraries using RNA from xylem, phloem and cambium, and green shoot tips and leaves from the P. trichocarpa Nisqually-1 genotype, as well as insect-attacked leaves of the P. trichocarpa x P. deltoides hybrid. Following careful selection of candidate cDNA clones, we used a combined strategy of paired end reads and primer walking to generate a set of 4,664 high-accuracy, sequence-verified FLcDNAs, which clustered into 3,990 putative unique genes. Mapping FLcDNAs to the poplar genome sequence combined with BLAST comparisons to previously predicted protein coding sequences in the poplar genome identified 39 FLcDNAs that likely localize to gaps in the current genome sequence assembly. Another 173 FLcDNAs mapped to the genome sequence but were not included among the previously predicted genes in the poplar genome. Comparative sequence analysis against Arabidopsis thaliana and other species in the non-redundant database of GenBank revealed that 11.5% of the poplar FLcDNAs display no significant sequence similarity to other plant proteins. By mapping the poplar FLcDNAs against transcriptome data previously obtained with a 15.5 K cDNA microarray, we identified 153 FLcDNA clones for genes that were differentially expressed in

  8. Effect of water regime on poplar cultivation

    Directory of Open Access Journals (Sweden)

    Letić Ljubomir

    2006-01-01

    Full Text Available The effect of water regime on the growth and development of plantations of hydrologically conditioned species, poplars was researched in the alluvial plain of the river Tamiš. The investigations were carried out during the period 2000-2003 on the area of FA "Opovo", KO Sakule, and the study results elucidate the very complex relationships between the hydrological conditions of the site and the growth and increment of the study poplar plantations, cl. I-214. .

  9. 混栽模式下转基因741杨抗虫性的初步研究%Studies on the insect resistance of mixed cultivating model of transgenic insect- resistance hybrid poplar 741

    Institute of Scientific and Technical Information of China (English)

    李超丽; 刘军侠; 姜文虎

    2011-01-01

    采用随机取样的方法,对河北省保定市大激店混栽模式下不同株系的转基因741杨pb29、pb00、pb17及对照741杨试验林进行了节肢动物群落调查,并初步分析了其群落组成、物种数量随时间的变化及优势种的发生发展规律.结果表明:混栽模式F的转基因741杨pb29、pb11和pb17的节肢动物种类组成基本一致,其群落多样性、均匀性均高于对照杨树,优势集中性均低于对照杨树,稳定性较好.混栽转基因741杨林内的优势种异色瓢虫、白毛蚜和杨白潜叶蛾在不同株系卜发生趋势基本一致,且在对照杨树上虫口数量较高.%The arthropod community structure was investigated in different transgenic hybrid poplar 741 varieties including pb29,pbll,pb17 and check741 using random sampling method in the paper. The purpose of this study is to analysis the changes over time about the structure of the arthropod community and the species quantity , the law of development of dominant species. The results showed that eompositive species were similar among the different transgenic hybrid poplar 741 varieties in this mixed cultivating model, the diversity indexes and evenness indexes of arthropod community in transgenic 741 poplar were higher than the control 741 poplar. The dominant value indexes were lower than the control 741 poplar,and the stability was better. The dominant species in this arthropod connunity including Harmonia axyridis Pallas, Chaitophoms populialbae Boyer de Fonscolombe and Leucoptera susinella Herrich- Sch ffer had similarly changing tendency, though they had a large quantity in the control 741 poplar.

  10. Response of transgenic poplar overexpressing cytosolic glutamine synthetase to phosphinothricin.

    Science.gov (United States)

    Pascual, María Belén; Jing, Zhong Ping; Kirby, Edward G; Cánovas, Francisco M; Gallardo, Fernando

    2008-01-01

    Glutamine synthetase (GS) is the main enzyme involved in ammonia assimilation in plants and is the target of phosphinothricin (PPT), an herbicide commonly used for weed control in agriculture. As a result of the inhibition of GS, PPT also blocks photorespiration, resulting in the depletion of leaf amino acid pools leading to the plant death. Hybrid transgenic poplar (Populus tremula x P. alba INRA clone 7171-B4) overexpressing cytosolic GS is characterized by enhanced vegetative growth [Gallardo, F., Fu, J., Cantón, F.R., García-Gutiérrez, A., Cánovas, F.M., Kirby, E.G., 1999. Expression of a conifer glutamine synthetase gene in transgenic poplar. Planta 210, 19-26; Fu, J., Sampalo, R., Gallardo, F., Cánovas, F.M., Kirby, E.G., 2003. Assembly of a cytosolic pine glutamine synthetase holoenzyme in leaves of transgenic poplar leads to enhanced vegetative growth in young plants. Plant Cell Environ. 26, 411-418; Jing, Z.P., Gallardo, F., Pascual, M.B., Sampalo, R., Romero, J., Torres de Navarra, A., Cánovas, F.M., 2004. Improved growth in a field trial of transgenic hybrid poplar overexpressing glutamine synthetase. New Phytol. 164, 137-145], increased photosynthetic and photorespiratory capacities [El-Khatib, R.T., Hamerlynck, E.P., Gallardo, F., Kirby, E.G., 2004. Transgenic poplar characterized by ectopic expression of a pine cytosolic glutamine synthetase gene exhibits enhanced tolerance to water stress. Tree Physiol. 24, 729-736], enhanced tolerance to water stress (El-Khatib et al., 2004), and enhanced nitrogen use efficiency [Man, H.-M., Boriel, R., El-Khatib, R.T., Kirby, E.G., 2005. Characterization of transgenic poplar with ectopic expression of pine cytosolic glutamine synthetase under conditions of varying nitrogen availability. New Phytol. 167, 31-39]. In vitro plantlets of GS transgenic poplar exhibited enhanced resistance to PPT when compared with non-transgenic controls. After 30 days exposure to PPT at an equivalent dose of 275 g ha(-1), growth

  11. Effects of mechanical damage and herbivore wounding on H2O2 metabolism and antioxidant enzyme activities in hybrid poplar leaves

    Institute of Scientific and Technical Information of China (English)

    AN Yu; SHEN Ying-bai; ZHANG Zhi-xiang

    2009-01-01

    The changes of hydrogen peroxide (H2O2) metabolism and antioxidant enzyme activities in a hybrid poplar (Populus simonii ×P. pyramidalis ‘Opera 8277') in response to mechanical damage (MD) and herbivore wounding (HW) were investigated to determine whether H2O2 could function as the secondary messenger in the signaling of systemic resistance. Results show that H2O2 was generated in wounded leaves through MD and HW treatments and systemically in unwounded leaves around the wounded leaves. The activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) were also enhanced. However, the H2O2 accumulation and antioxidant enzyme activities were inhibited in MD leaves through the pretreatment with DPI (which is a specific inhibitor of NADPH oxidase). The results of this study suggest that H2O2 could be systemically induced by MD and HW treatments, and H2O2 metabolism was closely related to the change in SOD, APX and CAT activities. A high level of antioxidant enzymes could decrease membrane lipid peroxidation levels and effectively induce plant defense responses.

  12. Ozone sensitivity in hybrid poplar correlates with insensitivity to both salicylic acid and jasmonic acid. The role of programmed cell death in lesion formation.

    Science.gov (United States)

    Koch, J R; Creelman, R A; Eshita, S M; Seskar, M; Mullet, J E; Davis, K R

    2000-06-01

    Our earlier studies demonstrated that the ozone-sensitive hybrid poplar clone NE-388 displays an attenuated level of ozone-, wound-, and phytopathogen-induced defense gene expression. To determine if this reduced gene activation involves signal transduction pathways dependent on salicylic acid (SA) and/or jasmonic acid (JA), we compared the responses of NE-388 and an ozone-tolerant clone, NE-245, to these signal molecules. JA levels increased in both clones in response to ozone, but only minimal increases in SA levels were measured for either clone. Treatment with SA and methyl jasmonate induced defense gene expression only in NE-245, indicating that NE-388 is insensitive to these signal molecules. DNA fragmentation, an indicator of programmed cell death (PCD), was detected in NE-245 treated with either ozone or an avirulent phytopathogen, but was not detected in NE-388. We conclude that these clones undergo two distinct mechanisms of ozone-induced lesion formation. In NE-388, lesions appear to be due to toxic cell death resulting from a limited ability to perceive and subsequently activate SA- and/or JA-mediated antioxidant defense responses. In NE-245, SA-dependent PCD precedes lesion formation via a process related to the PCD pathway activated by phytopathogenic bacteria. These results support the hypothesis that ozone triggers a hypersensitive response.

  13. Ozone-induced changes in photosynthesis and photorespiration of hybrid poplar in relation to the developmental stage of the leaves.

    Science.gov (United States)

    Bagard, Matthieu; Le Thiec, Didier; Delacote, Emilien; Hasenfratz-Sauder, Marie-Paule; Banvoy, Jacques; Gérard, Joëlle; Dizengremel, Pierre; Jolivet, Yves

    2008-12-01

    Young poplar trees (Populus tremula Michx. x Populus alba L. clone INRA 717-1B4) were subjected to 120 ppb of ozone for 35 days in phytotronic chambers. Treated trees displayed precocious leaf senescence and visible symptoms of injury (dark brown/black upper surface stippling) exclusively observed on fully expanded leaves. In these leaves, ozone reduced parameters related to photochemistry (Chl content and maximum rate of photosynthetic electron transport) and photosynthetic CO(2) fixation [net CO(2) assimilation, Rubisco (ribulose-1,5-bisphosphate carboxylase oxygenase) activity and maximum velocity of Rubisco for carboxylation]. In fully expanded leaves, the rate of photorespiration as estimated from Chl fluorescence was markedly impaired by the ozone treatment together with the activity of photorespiratory enzymes (Rubisco and glycolate oxidase). Immunoblot analysis revealed a decrease in the content of serine hydroxymethyltransferase in treated mature leaves, while the content of the H subunit of the glycine decarboxylase complex was not modified. Leaves in the early period of expansion were exempt from visible symptoms of injury and remained unaffected as regards all measured parameters. Leaves reaching full expansion under ozone exposure showed potential responses of protection (stimulation of mitochondrial respiration and transitory stomatal closure). Our data underline the major role of leaf phenology in ozone sensitivity of photosynthetic processes and reveal a marked ozone-induced inhibition of photorespiration.

  14. Progress and Strategies in Cross Breeding of Poplars in China

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The advance in intrasection and intersection cross breeding of poplars in China over the past 50 years is reviewed. Great progress has been made in Sections Leuce and Aigeiros, and satisfactory results of intersection hybridization have been achieved in the crossing between Sections Tacamahaca and Aigeiros. The modes of hybridization include single cross, double cross, triple cross, backcross, etc. It is known that using hybrids as parents to cross with other species or hybrids is an effective and easy way to obtain heterosis. Fast growth, cold and drought tolerance, pest and disease resistance, narrow crowns and rootage, etc. are breeding goals. The conventional artificial crossing is still a major breeding method, and a combination of the conventional artificial crossing with physical radiation and chemical induction can create new triploid individuals that possess higher yield potential. The super clones cultivated have already displayed enormous socioeconomic and ecological benefits in practice. Finally, the problems that investigators have to face at present are discussed as well as some strategies in poplar cross breeding in China.

  15. Impact of RAV1-engineering on poplar biomass production: a short-rotation coppice field trial.

    Science.gov (United States)

    Moreno-Cortés, Alicia; Ramos-Sánchez, José Manuel; Hernández-Verdeja, Tamara; González-Melendi, Pablo; Alves, Ana; Simões, Rita; Rodrigues, José Carlos; Guijarro, Mercedes; Canellas, Isabel; Sixto, Hortensia; Allona, Isabel

    2017-01-01

    Early branching or syllepsis has been positively correlated with high biomass yields in short-rotation coppice (SRC) poplar plantations, which could represent an important lignocellulosic feedstock for the production of second-generation bioenergy. In prior work, we generated hybrid poplars overexpressing the chestnut gene RELATED TO ABI3/VP1 1 (CsRAV1), which featured c. 80% more sylleptic branches than non-modified trees in growth chambers. Given the high plasticity of syllepsis, we established a field trial to monitor the performance of these trees under outdoor conditions and a SRC management. We examined two CsRAV1-overexpression poplar events for their ability to maintain syllepsis and their potential to enhance biomass production. Two poplar events with reduced expression of the CsRAV1 homologous poplar genes PtaRAV1 and PtaRAV2 were also included in the trial. Under our culture conditions, CsRAV1-overexpression poplars continued developing syllepsis over two cultivation cycles. Biomass production increased on completion of the first cycle for one of the overexpression events, showing unaltered structural, chemical, or combustion wood properties. On completion of the second cycle, aerial growth and biomass yields of both overexpression events were reduced as compared to the control. These findings support the potential application of CsRAV1-overexpression to increase syllepsis in commercial elite trees without changing their wood quality. However, the syllepsis triggered by the introduction of this genetic modification appeared not to be sufficient to sustain and enhance biomass production.

  16. Potential of the TCE-degrading endophyte Pseudomonas putida W619-TCE to improve plant growth and reduce TCE phytotoxicity and evapotranspiration in poplar cuttings.

    Science.gov (United States)

    Weyens, Nele; Truyens, Sascha; Dupae, Joke; Newman, Lee; Taghavi, Safiyh; van der Lelie, Daniel; Carleer, Robert; Vangronsveld, Jaco

    2010-09-01

    The TCE-degrading poplar endophyte Pseudomonas putida W619-TCE was inoculated in poplar cuttings, exposed to 0, 200 and 400 mg l(-1) TCE, that were grown in two different experimental setups. During a short-term experiment, plants were grown hydroponically in half strength Hoagland nutrient solution and exposed to TCE for 3 days. Inoculation with P. putida W619-TCE promoted plant growth, reduced TCE phytotoxicity and reduced the amount of TCE present in the leaves. During a mid-term experiment, plants were grown in potting soil and exposed to TCE for 3 weeks. Here, inoculation with P. putida W619-TCE had a less pronounced positive effect on plant growth and TCE phytotoxicity, but resulted in strongly reduced amounts of TCE in leaves and roots of plants exposed to 400 mg l(-1) TCE, accompanied by a lowered evapotranspiration of TCE. Dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), which are known intermediates of TCE degradation, were not detected.

  17. 转抗虫基因杨树对土壤微生物影响分析%Effects of transgenic insect-resistance hybrid poplar 741 groves on soil microorganisms

    Institute of Scientific and Technical Information of China (English)

    甄志先; 王进茂; 杨敏生

    2011-01-01

    In order to evaluate ecologic safety of transgenic insect-resistance hybrid poplar 741,the diversity of soil microflora and Bt toxin protein were systematically studied in the growth season. 4-year-old transgenic poplar 741 in the Heneshui district and Baoding district were examined. The toxin protein was found in the soil of 4-year-old test groves, whose peak content appeared in rhizosphere, and the longer the distances off the roots, the lower the contents.The distribution of toxin protein showed a descending trend: root tissue> root surface soil>rhizosphere soil> surface soil. The concentration of toxin protein decreased by degree of 10 times among different parts of soil. No toxin protein was found in rhizosphere of non-transformed clones. In the rhizosphere and roots surface soil of 4-year-old test groves, the amount of bacteria and actinomycetes and fungi varied with the changes of season. In spring, their amount began to increase gradually, reaching the maximum in June and July, and then decreased gradually. Between different transgenic clones and nontransgenic controls, during different seasons there were differences but no significant difference of their amounts appeared in rhizosphere and roots surface soil. The existence of toxin protein in soil showed no significant influence on the amounts of fungi, bacteria and actinomycetes. The result showed that distribution of Bt toxin protein was not related to the amount of microorganism. Transgenic poplar is ecofriendly in the grittiness soil.%以4年生转双抗虫基因741杨试验林为对象,研究了土壤中Bt毒蛋白的分布,及其在生长季节中土壤微生物种群数量的变化.结果表明:试验林土壤中发现了毒蛋白的存在,在转基因植株根围含量最高,距根系越远,含量逐渐降低.其毒蛋白分布趋势是根组织>根际土壤>根围土壤>地表土,其浓度一般呈10倍的等级降低,在非转基因对照植株根系周围未检

  18. Microarray and suppression subtractive hybridization analyses of gene expression in hybrid poplar (Populus alba × Populus tremula var. glandulosa) cell suspension cultures after exposure to NaCl.

    Science.gov (United States)

    Bae, Eun-Kyung; Lee, Hyoshin; Lee, Jae-Soon; Noh, Eun-Woon; Choi, Young-Im; Lee, Byung-Hyun; Choi, Dong-Woog

    2012-09-01

    The gene expression profiles of hybrid poplar (Populus alba × Populus tremula var. glandulosa) cells in suspension culture after exposure to salinity (NaCl) induced stress were examined by constructing two suppression subtractive hybridization (SSH) libraries. cDNA from non-treated cells was used as a driver and cDNA samples from cell suspension cultures exposed to 150 mM NaCl for 2 or 10 h were used as testers. Randomly selected clones from each SSH library were sequenced and 727 high-quality expressed sequence tags (ESTs) were obtained and analyzed. Four novel ESTs were identified. Between the two libraries, 542 unique SSH clones were selected for placement on a cDNA microarray. In total, 18 differentially expressed genes were identified with 4 and 12 genes being significantly differentially expressed 2 and 10 h after the treatment, respectively. Genes related to metabolism and protein synthesis and several genes whose protein products are implicated in salt or other abiotic stress-related responses were expressed in the salt-stressed cells.

  19. Mycorrhizal formation of nine ectomycorrhizal fungi on poplar cuttings

    Institute of Scientific and Technical Information of China (English)

    Lei MA; Xiaoqin WU; Ling ZHENG

    2008-01-01

    In order to discover which ectomycorrhizal-(ECM) fungi have better growth-promoting effects on poplars, cuttings from four poplar species were inoculated with nine species of ECM fungi by three methods. We investigated the status of mycorrhizal formation and the effects of these fungi on the growth of the poplars. The results show that Xrocomus chrysentero (Xc), Boletus edu-lis (Be), Pisolithus tinctorius (Pt) and Laccaria amethystea (La) formed clear ectomycorrhizal symbiosis with the poplar seedlings. Among these four ECM fungi, Xc had the greatest ability to develop mycorrhizae with all four poplar species. Be shows a greater ability to form mycor-rhizae with Populus deltoides Bartr cv. 'Lux' (Poplar I-69). Pt and La had relatively weaker abilities of colonization. The other five ECM fungal species, i.e., Scleroderma luteus (S1), Leeeinum scabrum (Ls), Boletus speeiosus (Bs), Calvatia eraniiformis (Cc) and Rhizopogen luteous (RI) could not easily form mycorrhizae with poplar seed-lings grown in sterilized substrates, but could do so in non-sterilized soil. With the method of drilling and inject-ing liquid inoculum, a simple operation, the mycorrhizal infection rates were higher than with the other two meth-ods, applying solid inoculum as fertilizer at the bottom of the pots and dipping roots in the inoculum slurry. P. simonii Carr. formed mycorrhizae with most of the nine ECM fungi. P. × euramericana (Dode) Guinier cv. 'San Martino' (Poplar 1-72) and P. deltoids Harvard × P. del-toids Lux (Poplar NL-351) had the highest compatibility with Pt. Poplar I-69 shows the highest compatibility with Xc. The study indicates that the optimal ECM fungi for poplars I-69, I-72 and NL-351 were Be, Xc and Pt, respectively. The optimal fungi for P. simonii Carr. were Xc and Be. These ECM fungi promoted the growth of the poplar seedlings significantly.

  20. Responses of hybrid poplar clones and red maple seedlings to ambient O(3) under differing light within a mixed hardwood forest.

    Science.gov (United States)

    Wei, C; Skelly, J M; Pennypacker, S P; Ferdinand, J A; Savage, J E; Stevenson, R E; Davis, D D

    2004-07-01

    The responses of ramets of hybrid poplar (Populus spp.) (HP) clones NE388 and NE359, and seedlings of red maple (Acer rubrum, L.) to ambient ozone (O(3)) were studied during May-September of 2000 and 2001 under natural forest conditions and differing natural sunlight exposures (sun, partial shade and full shade). Ambient O(3) concentrations at the study site reached hourly peaks of 109 and 98 ppb in 2000 and 2001, respectively. Monthly 12-h average O(3) concentrations ranged from 32.3 to 52.9 ppb. Weekly 12-h average photosynthetically active radiation (PAR) within the sun, partial shade and full shade plots ranged from 200 to 750, 50 to 180, and 25 to 75 micromol m(-2) s(-1), respectively. Ambient O(3) exposure induced visible foliar symptoms on HP NE388 and NE359 in both growing seasons, with more severe injury observed on NE388 than on NE359. Slight foliar symptoms were observed on red maple seedlings during the 2001 growing season. Percentage of total leaf area affected (%LAA) was positively correlated with cumulative O(3) exposures. More severe foliar injury was observed on plants grown within the full shade and partial shade plots than those observed on plants grown within the sun plot. Lower light availability within the partial shade and full shade plots significantly decreased net photosynthetic rate (Pn) and stomatal conductance (g(wv)). The reductions in Pn were greater than reductions in g(wv), which resulted in greater O(3) uptake per unit Pn in plants grown within the partial shade and full shade plots. Greater O(3) uptake per unit Pn was consistently associated with more severe visible foliar injury in all species and/or clones regardless of differences in shade tolerance. These studies suggest that plant physiological responses to O(3) exposure are likely complicated due to multiple factors under natural forest conditions.

  1. Global poplar root and leaf transcriptomes reveal links between growth and stress responses under nitrogen starvation and excess.

    Science.gov (United States)

    Luo, Jie; Zhou, Jing; Li, Hong; Shi, Wenguang; Polle, Andrea; Lu, Mengzhu; Sun, Xiaomei; Luo, Zhi-Bin

    2015-12-01

    Nitrogen (N) starvation and excess have distinct effects on N uptake and metabolism in poplars, but the global transcriptomic changes underlying morphological and physiological acclimation to altered N availability are unknown. We found that N starvation stimulated the fine root length and surface area by 54 and 49%, respectively, decreased the net photosynthetic rate by 15% and reduced the concentrations of NH4+, NO3(-) and total free amino acids in the roots and leaves of Populus simonii Carr. in comparison with normal N supply, whereas N excess had the opposite effect in most cases. Global transcriptome analysis of roots and leaves elucidated the specific molecular responses to N starvation and excess. Under N starvation and excess, gene ontology (GO) terms related to ion transport and response to auxin stimulus were enriched in roots, whereas the GO term for response to abscisic acid stimulus was overrepresented in leaves. Common GO terms for all N treatments in roots and leaves were related to development, N metabolism, response to stress and hormone stimulus. Approximately 30-40% of the differentially expressed genes formed a transcriptomic regulatory network under each condition. These results suggest that global transcriptomic reprogramming plays a key role in the morphological and physiological acclimation of poplar roots and leaves to N starvation and excess.

  2. Effects of in vitro ozone treatment on proteolysis of purified rubisco from two hybrid poplar clones. [Populus maximowizii x trichocarpa

    Energy Technology Data Exchange (ETDEWEB)

    Landry, L.G.; Pell, E.J. (Pennsylvania State Univ., University Park (USA))

    1989-04-01

    Plants exposed to ozone (O{sub 3}) exhibited symptoms of premature senescence, including early decline in quantity of rubisco. O{sub 3}-induced oxidation may cause changes in protein conformation of rubisco, resulting in enhanced proteolysis. To test this hypothesis, rubisco was purified from two hybrid clones of Populus maximowizii x trichocarpa, clones 388 and 245, and treated in vitro with O{sub 3} or air. Rubisco was then challenged with bromelain, papain, chymotrypsin, carboxypeptidase A, or endoproteinase Glu-C and percent degradation measured by SDS-PAGE and densitometric scanning of the gels. Degree of rubisco sensitivity to oxidation may be related to available sulfhydryl (SH) groups on the protein. The number of SH groups in native and denatured rubisco was measured for purified rubisco of both clones by DTNB titration method. The relationship between sensitivity to proteolysis and number and availability of SH groups is discussed.

  3. Gaseous NO2 effects on epidermis and stomata related physiochemical characteristics of hybrid poplar leaves: chemical elements composition, stomatal functions, photosynthesis and respiration

    Science.gov (United States)

    Mechanisms controlling effects of gaseous nitrogen dioxide on epidermis and stomata dynamics, and photosynthesis and respirations processes are still not fully understood. In this study, we used poplar as a model plant and investigated the effects of gaseous nitrogen dioxide (4 microliters per lite...

  4. 盐胁迫下根际细菌对杨树生长和生理的影响%The effect of plant growth promoting bacteria on growth and physiology of poplars under salt stress

    Institute of Scientific and Technical Information of China (English)

    岳东霞; 张要武

    2011-01-01

    为了明确根际细菌对杨树耐盐能力的影响,采用盆栽方法研究了不同浓度NaCl胁迫下,根际细菌Bacillus sp.和Arthrobacter sp.对杨树生长和生理的影响.结果表明,Bacillus sp.对杨树株高没有明显的影响;在无NaCl或NaCl浓度为85.5 mol/L时,显著降低杨树叶片细胞膜透性;在NaCl浓度为119.7 mmol/L时,显著提高杨树叶片叶绿素含量;在85.5和119.7 mmol/L NaCl胁迫下,均显著提高杨树叶片含糖量,Arthrobacter sp.在119.7 mmol/L NaCl胁迫下,显著增加杨树株高;在无NaCl或NaCl浓度为85.5 mmol/L时显著降低杨树叶片细胞膜透性,不同浓度NaCl处理,对杨树叶片叶绿素含量均没有明显的作用;在85.5和119.7 mmol/L NaCl胁迫下,均显著提高杨树叶片含糖量.不同水平NaCl胁迫下,Bacillus sp.和Arthrobacter sp.对杨树叶片含水量均没有显著影响.%To identify the effect of rhizobacteria on salt tolerance of poplars, the impact of plant growth promoting bacteria(PGPR)-Bacillus sp. and Arthrobacter sp. on growth and physiology of poplars seedlings have been investigated in pot experiment. The inoculation of Arthrobacter sp. significantly increased the height of poplar seedlings grown in the presence of 119.7 mmol/L NaCI salt; Bacillus sp. had no obvious impact on height of poplar seedlings stressed by different NaC1 concentrations. The two bacteria decreased the membrane permeability in the presence of both 0 and 85.5 mmol/L NaC1. At salt stress conditions (85.5 and 119. 7 mmol/L), Bacillus sp. and Arthrobacter sp. significantly enhanced the content of soluble sugar. Bacillus sp. significantly increased the content of chlorophyll at 119.7 mmol/L NaC1 salt; Arthrobacter sp. had no effect on the content of chlorophyll under different NaCl concentrations. Both of the two bacteria had no significant effect on relative water content of poplar seedling leaves.

  5. Comparative analysis of growth and photosynthetic characteristics of (Populus simonii × P. nigra × (P. nigra × P. simonii hybrid clones of different ploidides.

    Directory of Open Access Journals (Sweden)

    Xiyang Zhao

    Full Text Available To evaluate differences among poplar clones of various ploidies, 12 hybrid poplar clones (P. simonii × P. nigra × (P. nigra × P. simonii with different ploidies were used to study phenotypic variation in growth traits and photosynthetic characteristics. Analysis of variance showed remarkable differences for each of the investigated traits among these clones (P < 0.01. Coefficients of phenotypic variation (PCV ranged from 2.38% to 56.71%, and repeatability ranged from 0.656 to 0.987. The Pn (photosynthetic rate photosynthetic photon flux density (PPFD curves of the 12 clones were S-shaped, but the Pn-ambient CO2 (Ca curves were shaped like an inverted "V". The stomatal conductance (Gs-PPFD and transpiration rate (Tr-PPFD curves had an upward tendency; however, with increasing PFFD, the intercellular CO2 concentration (Ci-PPFD curves had a downward tendency in all of the clones. The Pn-PPFD and Pn-Ca curves followed the pattern of a quadratic equation. The average light saturation point and light compensation point of the triploid clones were the highest and lowest, respectively, among the three types of clones. For Pn-Ca curves, diploid clones had a higher average CO2 saturation point and average CO2 compensation point compared with triploid and tetraploid clones. Correlation analyses indicated that all investigated traits were strongly correlated with each other. In future studies, molecular methods should be used to analyze poplar clones of different ploidies to improve our understanding of the growth and development mechanisms of polyploidy.

  6. Growth Characteristics and Leaf Ultrastructures of Evergreen Poplar Clone Under Aluminum Stress%铝胁迫对常绿杨生长及叶肉细胞超微结构的影响

    Institute of Scientific and Technical Information of China (English)

    钱莲文; 吴文杰; 孙境蔚; 冯莹

    2016-01-01

    characteristics. However,when it is planted in tropical or subtropical areas,it faces a prominent issue of acidic soil in which aluminum is rich,which can bring adverse effects. In this study, the patterns of aluminum accumulation and distribution in the body, the response of leaf ultrastructure and the physiological indexes under the condition of acid aluminum were investigated. The study aims to reveal mechanism of the macro and micro structure of the evergreen Poplar adapting to aluminum stress,thus providing a theoretical basis for the widespread of the evergreen poplar in subtropical regions. [Method]In this study,and the evergreen poplar clone‘A-61/186’was grown in hydroponic solution for aluminum stress experiment,and the effects of aluminum stress on the growth,biomass,chlorophyll fluorescence indicator and leaf ultrastructures by using transmission electron microscopy( TEM) were studied systematically. [Result]The results showed that the acidic aluminum stress had an impact on the growth of the evergreen poplar; the acidic aluminum stress significantly decreased the growth of roots, stems,and leaves as well as biomass of the evergreen poplar,and it had a much greater impact on the underground part than the above ground part. In addition,aluminum was accumulated more readily in the roots than in the stems and leaf tissues. Chlorophyll fluorescence showed that the absorbed light was non-photochemical and dissipated under aluminum stress,which reduced its photosynthetic efficiency,thereby affecting the growth and biomass. Furthermore,the degree of injury to the mesophyll cell ultrastructure is consistent with the growth and chlorophyll fluorescence parameters,which indicated that the effects of aluminum stress on the evergreen poplar clone’s growth and biomass were directly related to the damage to the photosynthetic system.[Conclusion]With regards to the aluminum content in the evergreen poplar clone and the aluminum concentration that inhibited growth,the evergreen

  7. Poplar and its bacterial endophytes: coexistence and harmony

    Energy Technology Data Exchange (ETDEWEB)

    van der Lelie, D.; Taghavi, S.; Monchy, S.; Schwender, J.; Miller, L.; Ferrieri, R.; Rogers, A.; Zhu, W.; Weyens, N.; Vangronsveld, J.; Newman, L.

    2009-09-01

    Associations between plants and microorganisms are very complex and are the subject of an increasing number of studies. Here, we specifically address the relationship between poplar and its endophytic bacteria. The role and importance of endophytic bacteria in growth and development of their host plants is still underestimated. However, since many endophytes have a beneficial effect on their host, an improved understanding of the interaction between poplar and its endophytic bacteria has the potential to provide major breakthroughs that will improve the productivity of poplar. Endophytic bacteria can improve plant growth and development in a direct or indirect way. Direct plant growth promoting mechanisms may involve nitrogen fixation, production of plant growth regulators such as auxins, cytokinins and gibberellins, and suppression of stress ethylene synthesis by 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. Endophytic bacteria can indirectly benefit the plant by preventing the growth or activity of plant pathogens through competition for space and nutrients, antibiosis, production of hydrolytic enzymes, inhibition of pathogen-produced enzymes or toxins, and through systemic induction of plant defense mechanisms. Examples of applications for custom endophyte-host partnerships include improved productivity and establishment of poplar trees on marginal soils and the phytoremediation of contaminated soils and groundwater. A systems biology approach to understand the synergistic interactions between poplar and its beneficial endophytic bacteria represents an important field of research, which is facilitated by the recent sequencing of the genomes of poplar and several of its endophytic bacteria.

  8. Photosynthesis, water relations, and growth of two hybrid Populus genotypes during a severe drought

    Energy Technology Data Exchange (ETDEWEB)

    Dickmann, D.I.; Liu, Zuijun; Nguyen, Phu V.; Pregitzer, K.S. (Michigan State Univ., East Lansing, MI (USA))

    1992-01-01

    During the 1988 growing season in East Lansing, Michigan, only 1.53 cm of rain fell from mid-May to mid-July, causing a severe drought. Then, a period of near record precipitation commenced; 30.4 cm of rain fell from July 19 to October 4. Growth, photosynthesis, and water relations of hybrid poplar cultivars Eugenei and Tristis, which had been established in the spring of 1987 in plastic pots buried in the ground, were measured on several sunny days during the 1988 growing season. Pots were irrigated at two different rates, and half the pots received supplemental nitrogen fertilizer. On a seasonal basis, photosynthesis and water-use efficiency in both genotypes peaked in early July and declined thereafter. Stomatal conductances were low during the drought but increased substantially when the rains commenced. Whereas nitrogen level had little effect on leaf physiology, the low water treatment produced significant reductions in photosynthesis and conductance. Diurnal measurements were made on June 17 and July 12. On both days photosynthesis and conductances were higher in Tristis than in Eugenei, especially for plants in the high water treatments and on July 12, the most extreme period of the drought. Drought produced both stomatal and mesophyll limitations to photosynthesis in both clones, though these responses were more pronounced in Eugenei. This clone also showed very low water-use efficiencies in the low water treatment on July 12. Even though the physiology of Eugenei was more impacted by drought than Tristis, it still produced two to three times more biomass over the 2-year period of the study than did Tristis. 41 refs., 10 figs., 5 tabs.

  9. Analysis of 4,664 high-quality sequence-finished poplar full-length cDNA clones and their utility for the discovery of genes responding to insect feeding

    Directory of Open Access Journals (Sweden)

    Douglas Carl J

    2008-01-01

    Full Text Available Abstract Background The genus Populus includes poplars, aspens and cottonwoods, which will be collectively referred to as poplars hereafter unless otherwise specified. Poplars are the dominant tree species in many forest ecosystems in the Northern Hemisphere and are of substantial economic value in plantation forestry. Poplar has been established as a model system for genomics studies of growth, development, and adaptation of woody perennial plants including secondary xylem formation, dormancy, adaptation to local environments, and biotic interactions. Results As part of the poplar genome sequencing project and the development of genomic resources for poplar, we have generated a full-length (FL-cDNA collection using the biotinylated CAP trapper method. We constructed four FLcDNA libraries using RNA from xylem, phloem and cambium, and green shoot tips and leaves from the P. trichocarpa Nisqually-1 genotype, as well as insect-attacked leaves of the P. trichocarpa × P. deltoides hybrid. Following careful selection of candidate cDNA clones, we used a combined strategy of paired end reads and primer walking to generate a set of 4,664 high-accuracy, sequence-verified FLcDNAs, which clustered into 3,990 putative unique genes. Mapping FLcDNAs to the poplar genome sequence combined with BLAST comparisons to previously predicted protein coding sequences in the poplar genome identified 39 FLcDNAs that likely localize to gaps in the current genome sequence assembly. Another 173 FLcDNAs mapped to the genome sequence but were not included among the previously predicted genes in the poplar genome. Comparative sequence analysis against Arabidopsis thaliana and other species in the non-redundant database of GenBank revealed that 11.5% of the poplar FLcDNAs display no significant sequence similarity to other plant proteins. By mapping the poplar FLcDNAs against transcriptome data previously obtained with a 15.5 K cDNA microarray, we identified 153 FLcDNA clones

  10. Dissolved oxygen concentration affects hybrid striped bass growth

    Science.gov (United States)

    Management of dissolved oxygen (DO) concentration in ponds at night during the growing season is important because fish growth and yield are greater in ponds with higher nightly DO concentrations. Three studies were conducted to quantify performance traits and metabolic responses of hybrid striped b...

  11. Field test of new poplar clone in Shangdong Province

    Institute of Scientific and Technical Information of China (English)

    QIN Guang-hua; JIANG Yue-zhong; QIAO Yu-ling; B.Nottola

    2003-01-01

    Poplar is one of the dominant tree species for the establishment of fast growing plantations in Shandong Province. Eighteen poplar clones belonging to Populus aigeiros section were introduced from Italy, Turkey and domestic regions. Populus deltoides cv. 'Lux' I-69/55 (I-69), which was widely used in Shandong Province, China, was taken as control clone (I-69). Following a randomized complete block design, seedling test and controlled afforestation trials were carried out at Juxian County, Caoxian County and Laiyang City. The results showed that the poplar clone (Populus × euramericana cv. '102/74'), namely 102/74, performed well both in terms of adaptability and growth rate. The mean height of 13.9 m (H), diameter at breast height of 18.0 cm (DBH) and volume growth of 0.1445 m3 (V) were 2.2 %, 21.6% and 52.9 % higher than those of I-69 (CK), respectively, at the age of 5 years at three experimental sites. Moreover, the clone can be propagated easily and showed high resistance to poplar disease, pest as well as salinity and had longer growing period. Furthermore, wood basic density and fiber length of new poplar clone (102/74) were as same as I-69 (CK). It was concluded that the selected clone (102/74) was ideal for the establishment of fast-growing poplar plantations, especially for the pulpwood plantations in Shandong Province.

  12. Efectul aplicării lucrărilor de întreținere a terenului asupra acumulărilor de biomasă din culturile de plop hibrid [The effect of harrowing and weed control on biomass yields of hybrid poplar crops

    Directory of Open Access Journals (Sweden)

    Avăcăriței D

    2016-12-01

    Full Text Available Intensive hybrid poplar crops can produce an important biomass if adequate measures of management are being used. During the last years, there is a constant involvement on refining poplar cultivation technology, regarding installation, maintenance and harvesting, in order to obtain superior production at lower costs. The present study has analysed the effect of an experimental maintaining treatment (TI (harrowing and weed control on poplar crops’ biomass yields. The results were obtained after two vegetation seasons and compared with the results recorded in a control plot where no maintaining practices (TN were used. The experimental crop was set up in the spring of 2013, in the vicinity of Dornești site (Suceava County. Three hybrid poplar clones were tested (AF2, AF8 and Pannonia in each plot, and there were installed by long rods, using the 3.0 x 1.5 m spacing. The biomass was assessed for all the harvested individuals and every tree component using the gravimetric method. The experimental maintaining treatment (TI led to important differences between the two plots. The total biomass in TI plot was nearly eight-times superior to the biomass obtained in the control plot. All the three clones reacted significantly to the experimental treatment TI, even though minor differences were observed between the clones’ productivity. The effect of TI treatment was also substantial to the biomass’ structure on tree components. It is considered that the massive biomass increase was encouraged by a consistent shift of biomass proportion in the favour of the crown proportion (branches biomass, rather than subterranean elements.

  13. Growth of hybrid open access, 2009-2016.

    Science.gov (United States)

    Björk, Bo-Christer

    2017-01-01

    Hybrid Open Access is an intermediate form of OA, where authors pay scholarly publishers to make articles freely accessible within journals, in which reading the content otherwise requires a subscription or pay-per-view. Major scholarly publishers have in recent years started providing the hybrid option for the vast majority of their journals. Since the uptake usually has been low per journal and scattered over thousands of journals, it has been very difficult to obtain an overview of how common hybrid articles are. This study, using the results of earlier studies as well as a variety of methods, measures the evolution of hybrid OA over time. The number of journals offering the hybrid option has increased from around 2,000 in 2009 to almost 10,000 in 2016. The number of individual articles has in the same period grown from an estimated 8,000 in 2009 to 45,000 in 2016. The growth in article numbers has clearly increased since 2014, after some major research funders in Europe started to introduce new centralized payment schemes for the article processing charges (APCs).

  14. Establishment of high frequency shoot regeneration system in Himalayan poplar (Populus ciliata Wall. ex Royle) from petiole explants using Thidiazuron cytokinin as plant growth regulator

    Institute of Scientific and Technical Information of China (English)

    G Aggarwal; A Gaur; D K Srivastava

    2015-01-01

    Populus species are important resources for industry and in scientific study on biological and agricul-tural systems. Our objective was to enhance the frequency of plant regeneration in Himalayan poplar (Populus ciliata wall. ex Royle). The effect of TDZ alone and in combi-nation with adenine and NAA was studied on the regen-eration potential of petiole explants. The explants were excised from Himalayan poplar plants grown in glass-houses. After surface sterilization the explants were cul-tured on shoot induction medium. High percentage shoot regeneration (86%) was recorded on MS medium sup-plemented with 0.004 mg L-1 TDZ and 79.7 mg L-1 adenine. The regenerated shoots for elongation and multi-plication were transferred to MS ? 0.5 mg L-1 BAP ? 0.2 mg L-1 IAA ? 0.3 mg L-1 GA3. Root re-generation from shoots developed in vitro was observed on MS medium supplemented with 0.10 mg L-1 IBA. Hi-malayan poplar plantlets could be produced within 2 months after acclimatization in a sterile mixture of sand and soil. We developed a high efficiency plant regeneration protocol from petiole explants of P. ciliata.

  15. 植物生长调节剂抑制杨树及柳树飞絮效果研究%Study on Effect of Plant Growth Regulator on Inhibiting Flying in Poplar and Willow

    Institute of Scientific and Technical Information of China (English)

    迟晓莉; 于海鹰; 朱宝娣; 张勇

    2012-01-01

    the results of the study on effect of plant growth regulator (Yihua 1 )on inhibiting the flying in poplar and willow showed that,plant inhibitors were absorbed by plants, the formation of flower bud was inhibited, the flying in willow was bridled under the premise without affecting the normal growth of trees.%抑花一号植物生长调节剂抑制杨树及柳树飞絮效果研究结果表明,植物抑制剂被树体吸收后,可以控制花芽的形成,在不影响树木正常生长的前提下,达到控制飞絮的目的。

  16. Sequencing the genome of Marssonina brunnea reveals fungus-poplar co-evolution

    Directory of Open Access Journals (Sweden)

    Zhu Sheng

    2012-08-01

    Full Text Available Abstract Background The fungus Marssonina brunnea is a causal pathogen of Marssonina leaf spot that devastates poplar plantations by defoliating susceptible trees before normal fall leaf drop. Results We sequence the genome of M. brunnea with a size of 52 Mb assembled into 89 scaffolds, representing the first sequenced Dermateaceae genome. By inoculating this fungus onto a poplar hybrid clone, we investigate how M. brunnea interacts and co-evolves with its host to colonize poplar leaves. While a handful of virulence genes in M. brunnea, mostly from the LysM family, are detected to up-regulate during infection, the poplar down-regulates its resistance genes, such as nucleotide binding site domains and leucine rich repeats, in response to infection. From 10,027 predicted proteins of M. brunnea in a comparison with those from poplar, we identify four poplar transferases that stimulate the host to resist M. brunnea. These transferas-encoding genes may have driven the co-evolution of M. brunnea and Populus during the process of infection and anti-infection. Conclusions Our results from the draft sequence of the M. brunnea genome provide evidence for genome-genome interactions that play an important role in poplar-pathogen co-evolution. This knowledge could help to design effective strategies for controlling Marssonina leaf spot in poplar.

  17. Growing poplars for research with and without mycorrhizas

    Directory of Open Access Journals (Sweden)

    Anna eMüller

    2013-08-01

    Full Text Available During the last decades the importance of the genus Populus increased because the poplar genome has been sequenced and molecular tools for basic research are available. Furthermore, poplar species occur in different habitats and harbour large genetic variation, which can be exploited for economic applications and for increasing our knowledge on the basic molecular mechanisms of the woody life style. Poplars are, therefore, employed to unravel the molecular mechanisms of wood formation, stress tolerance, tree nutrition and interaction with other organisms such as pathogens or mycorrhiza. The basis of these investigations is the reproducible production of homogeneous plant material. In this method paper we describe techniques and growth conditions for the in vitro propagation of different poplar species (Populus × canescens, P. trichocarpa, P. tremula and P. euphratica and ectomycorrhizal fungi (Laccaria bicolor, Paxillus involutus as well as for their co-cultivation for ectomycorrhizal synthesis. Maintenance and plant preparation require different multiplication and rooting media. Growth systems to cultivate poplars under axenic conditions in agar and sand cultures with and without mycorrhizal fungi are described. Transfer of the plants from in vitro to in situ conditions is critical and hardening is important to prevent high mortality. Growth and vitality of the trees in vitro and outdoors with and without ectomycorrhizas are reported.

  18. A site dependent top height growth model for hybrid aspen

    Institute of Scientific and Technical Information of China (English)

    Tord Johansson

    2013-01-01

    In this study height growth models for hybrid aspen were developed using three growth equations. The mean age of the hybrid aspen was 21 years (range 15−51 years) with a mean stand density of 946 stems ha-1 (87−2374) and a mean diameter at breast height (over bark) of 19.6 cm (8.5−40.8 cm). Site index was also examined in relation to soil type. Multiple samples were collected for three types of soil: light clay, medium clay and till. Site index curves were constructed using the col-lected data and compared with published reports. A number of dynamic equations were assessed for modeling top-height growth from total age. A Generalized Algebraic Difference Approach model derived by Cieszewski (2001) performed the best. This model explained 99% of the observed variation in tree height growth and exhibited no apparent bias across the range of predicted site indices. There were no significant differences between the soil types and site indices.

  19. Key factors for causing poplar Ice Nucleation Active bacterial canker and its control techniques

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The isolation, culture and the active determination of poplar ice nucleation active (INA) bacteria and the inoculation tests in laboratory and field were conducted, and the varieties, distribution and number of poplar INA bacteria and its pathogenicity and freezing injury property were determined. The study results showed that the INA bacteria widely spread on poplar in Northeast China and caused the frozen injury for poplar under the frost condition in Spring or Autumn, which was the key factor to induce INA bacterial canker. Through evaluation and investigation of different poplar varieties and inoculation tests, fine disease-resistant varieties and strains of poplar suitable for Northeast China were selected. Further tests for strong seedling showed that burying cuttings in sand and covering with plastic film could effectively avoid the frostbite, frozen and drought damage, reduce INA bacteria infection, and promote poplar growth. INA bacterial canker was detected early by highly specialized antiserums of INA bacteria and the agglutinated test of ring-shaped boundary surface. The inducers such as streptomycin, phenylmercuric acetae, salicylic acid and heat-killed bacteria to immerse cuttings, have obvious induced disease-resistant effect. Before poplar sprouted in early spring, through spraying the solution of frostbite agent, the control effect also was obvious.

  20. Selection of black poplars for water use efficiency

    Directory of Open Access Journals (Sweden)

    Orlović Saša S.

    2002-01-01

    Full Text Available Photosynthesis, transpiration, water use efficiency (WUE and biomass production have been investigated in nine black poplar clones (section Aigeiros in three field experiments. Eastern cottonwood clones (Populus deltoides had the highest net photosynthesis and water use efficiency. European black poplar clones had the highest transpiration intensity. Correlation analysis showed that net photosynthesis was in a high positive correlation with biomass. Medium negative correlations existed between WUE and net photosynthesis, transpiration and biomass and WUE and biomass. The study showed a pronounced interclonal variability of the physiological and growth characters under study.

  1. 杂交杨木纤维中碳水化合物的稀酸催化分离%Dilute Acid-catalyzed Fractionation of Carbohydrates in Hybrid Poplar Fibers

    Institute of Scientific and Technical Information of China (English)

    张春辉; Troy Runge; 詹怀宇

    2012-01-01

    In this paper, the acid-catalyzed fractionation of pentosans and hexosans from hybrid poplar fibers was studied using a circulation reactor. Kinetic models of both pentosan and hexosan hydrolysis/degradation were crea- ted to predict the hydrolysis yield of both substances. The extraction conditions were varied, including a tempera- ture range of 140 - 170℃ , a sulfuric acid concentration range of 0.1% - 0.9% wt with a constant liquor-to-wood ratio of 6: 1. The yields of both substances were favored at high acid concentration and temperature, while pentosan being considerable more reactive. Under optimal conditions, 91 percent of pentosan could be separated from the fi- ber, while more than 93 percent of hexosan was retained in the solids. This study demonstrates that pentosan and hexosans could be fractionated from poplar fibers using acid hydrolysis and converted into liquid fuel and valued chemicals separately.%本文采用循环式反应器研究了杂交杨木纤维中聚戊糖和聚己糖在稀酸条件下的催化分离,分别得出了聚戊糖和聚己糖稀酸水解/降解的动力学模型,以预测在不同反应条件下戊糖和己糖的水解得率。反应条件为温度140~170℃,硫酸浓度0.1%~0.9%wt,液比为6:1。研究发现,较高的酸浓和温度对提高戊糖和己糖的得率都有利,但相同条件下聚戊糖的反应活性更高。经动力学模型优化得出,在较佳条件下有91%的聚戊糖可以以单体、低聚体及其降解产物的形式从杨木纤维中分离出来,同时超过93%的聚己糖可以以固体的形式保留在纤维中。研究表明,在适宜的稀酸催化条件下杂交杨木纤维中的碳水化合物可以得到很好的分离,为下一步戊糖和聚己糖的分别单独转化打下了基础,不仅可以充分利用木材生物质资源,而且为反应提供了相对均一的条件,从而提高反应选择性和产物的纯度。

  2. Molecular Dissection of Xylan Biosynthesis during Wood Formation in Poplar

    Institute of Scientific and Technical Information of China (English)

    Chanhui Lee; Quincy Teng; Ruiqin Zhong; Zheng-Hua Ye

    2011-01-01

    Xylan, being the second most abundant polysaccharide in dicot wood, is considered to be one of the factors contributing to wood biomass recalcitrance for biofuel production. To better utilize wood as biofuel feedstock, it is crucial to functionally characterize all the genes involved in xylan biosynthesis during wood formation. In this report, we inves-tigated roles of poplar families GT43 and GT8 glycosyltransferases in xylan biosynthesis during wood formation. There exist seven GT43 genes in the genome of poplar (Populus trichocarpa), five of which, namely PtrGT43A, PtrGT43B,PtrGT43C, PtrGT43D, and PtrGT43E, were shown to be highly expressed in the developing wood and their encoded proteins were localized in the Golgi. Comprehensive genetic complementation coupled with chemical analyses demonstrated that overexpression of PtrGT43A/B/E but not PtrGT43C/D was able to rescue the xylan defects conferred by the Arabidopsis irx9mutant, whereas overexpression of PtrGT43C/D but not PtrGT43A/B/E led to a complementation of the xyian defects in the Arabidopsis irx14 mutant. The essential roles of poplar GT43 members in xylan biosynthesis was further substantiated by RNAi down-regulation of GT43B in the hybrid poplar (Populus alba x tremula)leading to reductions in wall thickness and xylan content in wood, and an elevation in the abundance of the xylan reducing end sequence. Wood digestibility analysis revealed that cellulase digestion released more glucose from the wood of poplar GT43B RNAi lines than the control wood, indicating a decrease in wood biomass recalcitrance. Furthermore, RNAi down-regulation of another poplar wood-associated glycosyltransferase, PoGT8D, was shown to cause decreases in wall thickness and xylan content as well as in the abundance of the xylan reducing end sequence. Together, these findings demonstrate that the poplar GT43 mem-bers form two functionally non-redundant groups, namely PtrGT43A/B/E as functional orthologs of Arabidopsis IRX9 and Ptr

  3. Nitrogen ion utilization by tulip poplar (Liriodendron tulipifera L. ) seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Mann, L.K.

    1982-01-01

    Growth responses of one-year-old tulip poplar seedlings were determined for different nitrogen sources (HN/sub 4/NO/sub 3/, NH+/sub 4/, NO-/sub 3/, no nitrogen) at 336 ppm N in nutrient culture. At the end of three months, there were no significant differences in growth observed among treatments in terms of stem elongation, leaf area, and leaf size. After four months, however, seedlings of the NH/sub 4/NO/sub 3/ treatment exhibited significantly (P<0.05) greater growth (final weight gain and stem elongation) than all other nitrogen sorces. Growth was slightly less for the NO-/sub 3/ treatment plants, but compared with NH+/sub 4/ and no nitrogen treatment, both NH/sub 4/NO/sub 3/ and NO-/sub 3/ treatments exhibited significantly greater growth responses. NO-/sub 3/ is recommended as the sole nitrogen source, especially for small seedlings of tulip poplar.

  4. Isoprene emission-free poplars--a chance to reduce the impact from poplar plantations on the atmosphere.

    Science.gov (United States)

    Behnke, Katja; Grote, Rüdiger; Brüggemann, Nicolas; Zimmer, Ina; Zhou, Guanwu; Elobeid, Mudawi; Janz, Dennis; Polle, Andrea; Schnitzler, Jörg-Peter

    2012-04-01

    • Depending on the atmospheric composition, isoprene emissions from plants can have a severe impact on air quality and regional climate. For the plant itself, isoprene can enhance stress tolerance and also interfere with the attraction of herbivores and parasitoids. • Here, we tested the growth performance and fitness of Populus × canescens in which isoprene emission had been knocked down by RNA interference technology (PcISPS-RNAi plants) for two growing seasons under outdoor conditions. • Neither the growth nor biomass yield of the PcISPS-RNAi poplars was impaired, and they were even temporarily enhanced compared with control poplars. Modelling of the annual carbon balances revealed a reduced carbon loss of 2.2% of the total gross primary production by the absence of isoprene emission, and a 6.9% enhanced net growth of PcISPS-RNAi poplars. However, the knock down in isoprene emission resulted in reduced susceptibility to fungal infection, whereas the attractiveness for herbivores was enhanced. • The present study promises potential for the use of non- or low-isoprene-emitting poplars for more sustainable and environmentally friendly biomass production, as reducing isoprene emission will presumably have positive effects on regional climate and air quality. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  5. Regulation of a metallothionein-growth hormone hybrid gene in bovine papilloma virus.

    OpenAIRE

    Pavlakis, G N; Hamer, D H

    1983-01-01

    We have constructed bovine papilloma virus recombinants carrying a hybrid gene in which human growth hormone structural sequences are fused to the promoter and presumptive control region of the mouse metallothionein-I gene. Mouse cells transformed with the recombinants synthesize metallothionein-growth hormone hybrid mRNA with the same 5' end as metallothionein mRNA. Hybrid mRNA is inducible by cadmium but not by dexamethasone, whereas the chromosomal metallothionein genes in the same cells a...

  6. Controlled isotropic or anisotropic nanoscale growth of coordination polymers: formation of hybrid coordination polymer particles.

    Science.gov (United States)

    Lee, Hee Jung; Cho, Yea Jin; Cho, Won; Oh, Moonhyun

    2013-01-22

    The ability to fabricate multicompositional hybrid materials in a precise and controlled manner is one of the primary goals of modern materials science research. In addition, an understanding of the phenomena associated with the systematic growth of one material on another can facilitate the evolution of multifunctional hybrid materials. Here, we demonstrate precise manipulation of the isotropic and/or anisotropic nanoscale growth of various coordination polymers (CPs) to obtain heterocompositional hybrid coordination polymer particles. Chemical composition analyses conducted at every growth step reveal the formation of accurately assembled hybrid nanoscale CPs, and microscopy images are used to examine the morphology of the particles and visualize the hybrid structures. The dissimilar growth behavior, that is, growth in an isotropic or anisotropic fashion, is found to be dependent on the size of the metal ions involved within the CPs.

  7. Effects of Saccharomyces cerevisiae cell wall extract and poplar propolis ethanol extract supplementation on growth performance, digestibility, blood profile, fecal microbiota and fecal noxious gas emissions in growing pigs.

    Science.gov (United States)

    Li, Jian; Kim, In H

    2014-06-01

    A total of 105 growing pigs (24.91 ± 1.06 kg) were used in a 6-week trial to investigate the effects of including Saccharomyces cerevisiae cell wall extract and poplar propolis ethanol extract (SPE) in the diet on growth performance, digestibility, blood profiles, fecal microbiota and fecal noxious gas emissions. Pigs were randomly allocated to one of three dietary treatments (seven pens/treatment, five pigs/pen) according to initial body weight and sex (two gilts and three barrows). Treatments consisted of a corn soybean meal basal diet supplemented with 0, 0.05 or 0.10% SPE. There was a significant linear improvement (P red blood cells and white blood cells concentration were not significantly (P > 0.05) affected by SPE supplementation in the diets. In conclusion, results indicate that dietary SPE supplementation can improve growth performance, digestibility and fecal microbiota, and decrease fecal gas emissions in growing pigs. © 2014 Japanese Society of Animal Science.

  8. Control tactics of poplar diseases in China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Based on the present studies and literatures about the poplar diseases in China, the present study situation of poplar disease was introduced in this paper. 31 kinds of poplar diseases were collected of which there were 14 kinds of leaves disease, 11 kinds of branch disease, 4 kinds of root disease, 2 kinds of stand rot. Each poplar species was studied on the harm, distribution, symptom, pathogens, occurrence regulation and control measures. According to previously studies, the sustained control tactics of poplar disease were summarized in this paper.

  9. Hybrid accretionary/collisional mechanism of Paleozoic Asian continental growth

    Science.gov (United States)

    Schulmann, Karel; Lexa, Ondrej; Janousek, Vojtech; Pavla, Stipska; Yingde, Jiang; Alexandra, Guy; Min, Sun

    2016-04-01

    Continental crust is formed above subduction zones by well-known process of "juvenile crust growth". This new crust is in modern Earth assembled into continents by two ways: (i) short-lived collisions of continental blocks with the Eurasian continent along the "Alpine-Himalayan collisional/interior orogens" in the heart of the Pangean continental plates realm; and (ii) long lived lateral accretion of ocean-floor fragments along "circum-Pacific accretionary/peripheral orogens" at the border of the Pacific oceanic plate. This configuration has existed since the late Proterozoic, when the giant accretionary Terra Australis Orogen developed at periphery of an old Palaeo-Pacific ocean together with collisional Caledonian and Variscan orogens. At the same time, the large (ca. 9 millions km2) Central Asian Orogenic Belt (CAOB) developed in the NE part of the Pangea. This orogen reveals features of both peripheral and interior orogens, which implies that the generally accepted "peripheral-accretionary" and "interior- collisional" paradigm is not applicable here. To solve this conundrum a new model of unprecedented Phanerozoic continental growth is proposed. In this model, the CAOB precursor evolved at the interface of old exterior and young interior oceans. Subsequently, the new lithospheric domain was transferred by advancing subduction into the interior of the Pangean mostly continental realm. During this process the oceanic crust was transformed into continental crust and it was only later when this specific lithosphere was incorporated into the Asian continent. If true, this concept represents revolutionary insight into processes of crustal growth explaining the enigma of anchoring hybrid lithosphere inside a continent without its subduction or Tibetan-type thickening.

  10. 不同水分下腐殖酸对杨树生长和土壤肥力的影响%The Effects of Humic Acid Under Different Water Levels on Poplar Growth and Soil Fertility

    Institute of Scientific and Technical Information of China (English)

    张敬敏; 桑茂鹏; 刘春生; 邢尚军

    2013-01-01

    In order to explore poplar high-yield water and fertilizer condition, the effect of humic acid and inorganic fertilizer on poplar growth and soil fertility were conducted under low, normal and high three different water levels by pot experiment. The result showed that: there was no significant difference on the dry weight under low water treatment between the application of humic acid and inorganic fertilizer, but had significant difference under regular and high water treatment. Under the three different water levels, total average dry weights were 14.60 g, 96.03 g and 230.00 g respectively which had significant difference between them. Compared with inorganic fertilizer under the same water levels, the application of humic acid significantly decreased the contents of nitrate nitrogen and available P, K, increased the content of ammonium nitrogen;significantly increased the contents of total C and correspondingly the humus activity; and had significantly enhanced the activity of polyphenol oxidase enzyme, but had little effect on catalase enzyme. As for the urease enzyme, the application of humic acid significantly increased urease enzyme in the low and regular water treatment, and had no significant difference in the high water treatment. To sum up, application of humid acid were blocked under low water treatment, but it had significant effects on poplar growth and soil fertility under regular and high water treatment.%为了探索杨树高产栽培水肥措施,采用盆栽试验,研究低水(W1)、常规水分(W2)和高水(W3)3种水分条件下,配施腐殖酸(M)和单施无机肥对杨树生长和土壤肥力的影响。结果表明:低水条件下,配施腐殖酸与单施无机肥处理杨树总生物量无显著差异,而在常规水和高水条件下有显著差异。低水、常规水和高水条件下,杨树平均总生物量分别为14.60 g、96.03 g和230.00 g ,差异明显。相同水分下,配施腐殖酸降低了土壤硝态氮、

  11. Growth response of Larix hybrids between L. kaempferi and L. gmelinii var. japonica with altitudinal gradient

    Energy Technology Data Exchange (ETDEWEB)

    Kisanuki, Hiromitsu; Kurahashi, Akio; Takahashi, Yasuo [Tokyo Univ. Forest, Hokkaido (Japan)

    1995-12-31

    To test the adaptability of Japanese larch, Dahurian larch and their hybrid to the environment in Hokkaido, these three materials were planted and surveyed of their survival and growth for 30 years at four elevation in central Hokkaido, northern Japan. Japanese larch showed low adaptation with high mortality affected by voles at every elevation. Dahurian larch has high vole resistance but showed high mortality caused by the infection of Armillaria root rot. Hybrid could persist through low to high elevation. Only hybrid showed enough growth at the highest elevation. Stress tolerance of hybrid was confirmed under high altitudinal condition. 12 refs, 4 figs, 3 tabs

  12. Evaluation of soil nutrient status in poplar forest soil by soil nutrient systematic approach

    Institute of Scientific and Technical Information of China (English)

    YUChang-bing; CHENFang; LUOZhi-jian; CHENWei-wen

    2004-01-01

    A study was conducted to evaluate the soil nutrient status of poplar plantation by Soil Nutrient Systematic Approach(SNSA) in Jianghan Plain, Hubei Province, China. Soil physiochemical properties were analyzed in laboratory through collection soil samples of study site. Ten treatments of application different fertilizers were designed such as CK, optimum treatment (N, P,K, Zn), -N(P, K, Zn), -P(N, K, Zn), -K(N, P, Zn), +Mg(N, P, K, Zn, Mg), -Zn (N,P,K), +2P(N, 2P, K, Zn), +2K(N, P, 2K, Zn), and 2N+2P+2K(2N, 2P, 2K, Zn) for field experiment to test the effect on tree height, diameter (DBH) growth, and dry weight of poplar.The results showed that there was no significant difference in tree heights between treatments with different fertilizers, diameter growth of poplar trees in treatments of lack of N and Zn was significantly slower than that of trees in optimum treatment, and dry weight of poplar dropped significantly for treatment of CK as well as treatments without application N and Zn. It is concluded that N and Zn were main limiting factor for poplar growth. Results from laboratory analysis and field experiment were uniform perfectly, which proved that SNSA was reliable in evaluating soil nutrient status of poplar plantation.

  13. Application of pre-emergence herbicides in poplar nursery production

    Institute of Scientific and Technical Information of China (English)

    Verica Vasic; Sasa Orlovic; Predrag Pap; Branislav Kovacevic; Milan Drekic; Leopold Poljakovic Pajnik; Zoran Galic

    2015-01-01

    In addition to pests and diseases, weeds are a major problem in poplar nursery production. The possibili-ties of herbicide application in juvenile poplar growth were researched, taking into account that weeds are one of the main limiting factors. The following pre-emergence herbi-cides were tested: acetochlor, S-metolachlor, metribuzin, oxifluorfen, and dimethenamid during two vegetation sea-sons at two locations, which differed by the soil physico-chemical characteristics. The study results show that the number of weeds on sample plots was significantly reduced by the tested herbicides when compared to control plots. The highest reduction in the number of weeds was achieved using the herbicides acetochlor and metribuzin. However, me-tribuzin showed a phytotoxic effect on sandy soil. Metribu-zin application is recommended only on the soils with higher contents of organic matter, where the phytotoxic effect was absent. Acetochlor, S-metolachlor, oxifluorfen, and dime-thenamid were not phytotoxic to poplars and can be used for weed suppression in the production of poplar plants.

  14. Ploidy and Hybridity Effects on Growth Vigor and Gene Expression in Arabidopsis thaliana Hybrids and Their Parents.

    Science.gov (United States)

    Miller, Marisa; Zhang, Changqing; Chen, Z Jeffrey

    2012-04-01

    Both ploidy and hybridity affect cell size and growth vigor in plants and animals, but the relative effects of genome dosage and hybridization on biomass, fitness, and gene expression changes have not been systematically examined. Here we performed the first comparative analysis of seed, cell, and flower sizes, starch and chlorophyll content, biomass, and gene expression changes in diploid, triploid, and tetraploid hybrids and their respective parents in three Arabidopsis thaliana ecotypes: Columbia, C24, and Landsberg erecta (Ler). Ploidy affects many morphological and fitness traits, including stomatal size, flower size, and seed weight, whereas hybridization between the ecotypes leads to altered expression of central circadian clock genes and increased starch and chlorophyll content, biomass, and seed weight. However, varying ploidy levels has subtle effects on biomass, circadian clock gene expression, and chlorophyll and starch content. Interestingly, biomass, starch content, and seed weight are significantly different between the reciprocal hybrids at all ploidy levels tested, with the lowest and highest levels found in the reciprocal triploid hybrids, suggesting parent-of-origin effects on biomass, starch content, and seed weight. These findings provide new insights into molecular events of polyploidy and heterosis, as well as complex agronomic traits that are important to biomass and seed production in hybrid and polyploid crops.

  15. Repeated unidirectional introgression towards Populus balsamifera in contact zones of exotic and native poplars

    NARCIS (Netherlands)

    Thompson, S.L.; Lamothe, M.; Meirmans, P.G.; Périnet, P.; Isabel, N.

    2010-01-01

    As the evolutionary significance of hybridization is largely dictated by its extent beyond the first generation, we broadly surveyed patterns of introgression across a sympatric zone of two native poplars (Populus balsamifera, Populus deltoides) in Quebec, Canada within which European exotic Populus

  16. Effects of irrigating poplar energy crops with landfill leachate on soil micro- and meso-fauna

    Science.gov (United States)

    Jill A. Zalesny; David R. Coyle; Ronald S. Jr. Zalesny; Adam H. Wiese

    2009-01-01

    Increased municipal solid waste generated worldwide combined with substantial demand for renewable energy has prompted testing and deployment of woody feedstock production systems that reuse and recycle wastewaters as irrigation and fertilization for the trees. Populus species and hybrids (i.e., poplars) are ideal for such systems given their fast...

  17. An efficient Agrobacterium-mediated transformation system for poplar.

    Science.gov (United States)

    Movahedi, Ali; Zhang, Jiaxin; Amirian, Rasoul; Zhuge, Qiang

    2014-06-13

    Poplar is a model system for the regeneration and genetic transformation of woody plants. To shorten the time required for studies of transgenic poplar, efforts have been made to optimize transformation methods that use Agrobacterium tumefaciens. In this study, an Agrobacterium infective suspension was treated at 4 °C for at least 10 h before infecting explants. By transforming the Populus hybrid clone "Nanlin895" (Populus deltoides×P. euramericana) with Agrobacterium harboring the PBI121:CarNAC6 binary vector, we showed that the transformation efficiency was improved significantly by multiple independent factors, including an Agrobacterium infective suspension with an OD600 of 0.7, an Agrobacterium infection for 120 min, an Agrobacterium infective suspension at a pH of 5.0, an acetosyringone concentration of 200 µM, a cocultivation at 28 °C, a cocultivation for 72 h and a sucrose concentration of 30 g/L in the cocultivation medium. We also showed that preculture of wounded leaf explants for two days increased the regeneration rate. The integration of the desired gene into transgenic poplars was detected using selective medium containing kanamycin, followed by southern blot analysis. The expression of the transgene in the transgenic lines was confirmed by northern blot analysis.

  18. An Efficient Agrobacterium-Mediated Transformation System for Poplar

    Directory of Open Access Journals (Sweden)

    Ali Movahedi

    2014-06-01

    Full Text Available Poplar is a model system for the regeneration and genetic transformation of woody plants. To shorten the time required for studies of transgenic poplar, efforts have been made to optimize transformation methods that use Agrobacterium tumefaciens. In this study, an Agrobacterium infective suspension was treated at 4 °C for at least 10 h before infecting explants. By transforming the Populus hybrid clone “Nanlin895” (Populus deltoides × P. euramericana with Agrobacterium harboring the PBI121:CarNAC6 binary vector, we showed that the transformation efficiency was improved significantly by multiple independent factors, including an Agrobacterium infective suspension with an OD600 of 0.7, an Agrobacterium infection for 120 min, an Agrobacterium infective suspension at a pH of 5.0, an acetosyringone concentration of 200 µM, a cocultivation at 28 °C, a cocultivation for 72 h and a sucrose concentration of 30 g/L in the cocultivation medium. We also showed that preculture of wounded leaf explants for two days increased the regeneration rate. The integration of the desired gene into transgenic poplars was detected using selective medium containing kanamycin, followed by southern blot analysis. The expression of the transgene in the transgenic lines was confirmed by northern blot analysis.

  19. Hybrid Thin Film Organosilica Sol-Gel Coatings To Support Neuronal Growth and Limit Astrocyte Growth.

    Science.gov (United States)

    Capeletti, Larissa Brentano; Cardoso, Mateus Borba; Dos Santos, João Henrique Zimnoch; He, Wei

    2016-10-07

    Thin films of silica prepared by a sol-gel process are becoming a feasible coating option for surface modification of implantable neural sensors without imposing adverse effects on the devices' electrical properties. In order to advance the application of such silica-based coatings in the context of neural interfacing, the characteristics of silica sol-gel are further tailored to gain active control of interactions between cells and the coating materials. By incorporating various readily available organotrialkoxysilanes carrying distinct organic functional groups during the sol-gel process, a library of hybrid organosilica coatings is developed and investigated. In vitro neural cultures using PC12 cells and primary cortical neurons both reveal that, among these different types of hybrid organosilica, the introduction of aminopropyl groups drastically transforms the silica into robust neural permissive substrate, supporting neuron adhesion and neurite outgrowth. Moreover, when this organosilica is cultured with astrocytes, a key type of glial cells responsible for glial scar response toward neural implants, such cell growth promoting effect is not observed. These findings highlight the potential of organo-group-bearing silica sol-gel to function as advanced coating materials to selectively modulate cell response and promote neural integration with implantable sensing devices.

  20. Feasibility of poplar foliages as bio-monitors for organochlorine pesticides in air

    Institute of Scientific and Technical Information of China (English)

    DAI TianYou; ZHU XiaoHua; WANG Wei; MENG Wei; YU YunJiang; LI FaSheng; YANG YongLiang; LIU Feng

    2009-01-01

    The feasibility of poplar (P. tomentosa) foliages as passive biomonitors for organochlorine pesticides In air was explored. The accumulation patterns of poplar foliages for HCHs, DDTs and HCB were similar, the amount of HCHs, DDTs and HCB increased with foliage growth in spring, and decreased thereafter. There was no obvious distinction in the accumulation styles between the adult leaf and the leaf-litter. This accumulation pattern is likely related to the growing process of the poplar foliage, and was ob-served for the first time in our work, giving an evidence for the "bud burst effect" in plants. The tech-nical HCH and DDT were used largely in history and not used in recent years, but there was a little usage of lindane and new input of o,p'DDT in recent years, and dicofol usage may be the main source of o,p'-DDT. Concentrations of HCHs, DDTs and HCB in poplar foliages were similar to those in pine needles at the corresponding period, and there is a positive strong correlation between OCP concen-tration data of two kinds of trees. It presents no difference in the accumulation style between two kinds of trees. The level of OCPs in the poplar foliage reflected the pollution status of OCPs in air. The result of this work showed that the poplar foliage can be used as the bio-monitor of OCPs in air.

  1. Hydrologic Evaluation of a Humid Climate Poplar Phytoremediation Barrier

    Science.gov (United States)

    Swensen, K.; Rabideau, A. J.

    2016-12-01

    The emplacement of hybrid poplar trees to function as phytoremediation barriers is an appealing and sustainable groundwater management strategy because of low maintenance costs and the potential to extract large amounts of groundwater without pumping. While the effectiveness of poplar barriers has been assessed by groundwater quality monitoring, less attention has been given to physical hydrologic evaluations needed to improve barrier designs. In this research, a five year hydrologic evaluation was conducted at a poplar phytoremediation site in western NY, with the goal of quantifying ETg (evapotranspiration from groundwater) as a measure of the barrier's effectiveness in a humid climate. To consider transpiration from both vadose zone and groundwater, the hydrologic evaluation included four components: physical ET measurements, theoretical ET calculations, analysis of diurnal groundwater table fluctuations, and vadose zone modeling. The direct measurements of ETT (total) were obtained using sap flow meters installed on multiple trees within the barrier. These data were interpreted using a regression model that included theoretical ET calculations and site-specific measurements of weather parameters and poplar trunk area. Application of this model was challenged by the spatial variation in rooting depth as determined by tree excavations. To further quantify the removal of groundwater by the phytobarrier (ETg), the White Method was applied to interpret diurnal groundwater fluctuations from monitoring wells located within the barrier, in conjunction with a variably saturated-saturated flow model configured to confirm water extraction from ETg. Taken together, the results of this five year hydrologic evaluation highlight the complexity in quantifying humid climate groundwater extraction, as a large number of variables were found to influence these rates. Improved understanding of these controls will contribute to improved barrier designs that maximize ETg.

  2. Effect of Genetically Modified Poplars on Soil Microbial Communities during the Phytoremediation of Waste Mine Tailings▿†

    Science.gov (United States)

    Hur, Moonsuk; Kim, Yongho; Song, Hae-Ryong; Kim, Jong Min; Choi, Young Im; Yi, Hana

    2011-01-01

    The application of transgenic plants to clean up environmental pollution caused by the wastes of heavy metal mining is a promising method for removing metal pollutants from soils. However, the effect of using genetically modified organisms for phytoremediation is a poorly researched topic in terms of microbial community structures, despite the important role of microorganisms in the health of soil. In this study, a comparative analysis of the bacterial and archaeal communities found in the rhizosphere of genetically modified (GM) versus wild-type (WT) poplar was conducted on trees at different growth stages (i.e., the rhizospheres of 1.5-, 2.5-, and 3-year-old poplars) that were cultivated on contaminated soils together with nonplanted control soil. Based on the results of DNA pyrosequencing, poplar type and growth stages were associated with directional changes in the structure of the microbial community. The rate of change was faster in GM poplars than in WT poplars, but the microbial communities were identical in the 3-year-old poplars. This phenomenon may arise because of a higher rate and greater extent of metal accumulation in GM poplars than in naturally occurring plants, which resulted in greater changes in soil environments and hence the microbial habitat. PMID:21890678

  3. EVALUATION OF HYBRIDIZATION BETWEEN PANGASIUS DJAMBAL BLEEKER 1846 AND PANGASIANODON HYPOPHTHALMUS (SAUVAGE 1878: BIOMETRIC CHARACTERIZATION AND GROWTH ANALYSIS

    Directory of Open Access Journals (Sweden)

    Rudhy Gustiano

    2007-06-01

    Full Text Available Possible use of pangasiid hybrids in aquaculture might generate potential impacts on wild populations. Therefore, rapid identification tools in the field such as growth rate are urgently needed. This study examines morphological characters and growth performance of P. djambal and P. hypophthalmus and their reciprocal hybrids. A detailed morphological study analysed 32 morphometric measurements and 5 meristic counts on hybrids of Pangasius djambal and P. hypophthalmus. Morphometric analysis and meristic counts showed that the reciprocal hybrids have intermediate characters except for gill rakers number which were lower than that of parental species. In general, the hybrids have tendency to be like P. hypophthalmus rather than P. djambal. The only typical character P. djambal appearing in hybrids is teeth shape, both vomerine and palatine. It was shown that the true hybrids have seven pelvic fin rays. Eight months of growth comparison in earthen ponds showed that the hybrids have a better performance for specific growth rate than the parental stock.

  4. Cadmium phytoextraction potential of poplar clones (Populus spp.)

    Energy Technology Data Exchange (ETDEWEB)

    Pilipovic, A.; Orlovic, S.; Petrovic, N. [Faculty of Agriculture, Inst. of Lowland Forestry and Environment, Novi Sad (Czechoslovakia); Nikolic, N.; Krstic, B. [Faculty of Natural Sciences, Dept. of Biology and Ecology, Novi Sad (Czechoslovakia)

    2005-04-01

    Biomass production, leaf number and area, photosynthetic and dark respiration rates, leaf concentration of photosynthetic pigments, nitrate reductase activity, as well as cadmium concentrations in leaves, stem, and roots were measured in poplar clones PE 4/68, B-229, 665, and 45/51. Plants were grown hydroponically under controlled conditions and treated with two different cadmium (Cd) concentrations (10{sup -5} and 10{sup -7} M) in the same background solution (Hoagland's solution). The presence of Cd did not cause serious disturbance of growth and physiological parameters in the studied poplar clones. Cd concentrations in plant tissues reflected external concentrations. In treated plants, root contents increased from 38.57 to 511.51 ppm, leaf contents from 0.91 to 7.50, while stem contents ranged from 1.37 to 9.50 ppm. (orig.)

  5. Daytime and nighttime wind differentially affects hydraulic properties and thigmomorphogenic response of poplar saplings.

    Science.gov (United States)

    Huang, Ping; Wan, Xianchong; Lieffers, Victor J

    2016-05-01

    This study tested how wind in daytime and nighttime affects hydraulic properties and thigmomorphogenic response of poplar saplings. It shows that wind in daytime interrupted water balance of poplar plants by aggravating cavitation in the stem xylem under high xylem tension in the daytime, reducing water potential in midday and hence reducing gas exchange, including stomatal conductance and CO2 assimilation. The wind blowing in daytime significantly reduced plant growth, including height, diameter, leaf size, leaf area, root and whole biomass, whereas wind blowing in nighttime only caused a reduction in radial and height growth at the early stage compared with the control but decreased height:diameter ratios. In summary, the interaction between wind loading and xylem tension exerted a negative impact on water balance, gas exchanges and growth of poplar plants, and wind in nighttime caused only a small thigmomorphogenic response.

  6. Influence of growth rate and starvation on fluorescent in situ hybridization of Rhodopseudomonas palustris

    NARCIS (Netherlands)

    Oda, Y; Slagman, SJ; Meijer, WG; Forney, LJ; Gottschal, JC

    In situ hybridization with a fluorescently labeled 16S rRNA-targeted probe was examined using Rhodopseudomonas palustris as a model organism, which had been grown at different rates and under different conditions of growth and starvation. The specific growth rate did not affect the percentage of

  7. Effect of dissolved oxygen concentration on growth of fingerling hybrid striped bass

    Science.gov (United States)

    Management of dissolved oxygen (DO) concentration in production ponds is important because fish growth and yield are greater in ponds with higher DO concentrations. The purpose of this study was to evaluate growth and metabolic responses of hybrid striped bass (Morone chrysops x M. saxatilis; HSB) f...

  8. Effect of Alnus glutinosa on hybrid populus growth and soil nitrogen concentration in a mixed plantation

    Science.gov (United States)

    Jeffrey O. Dawson; Edward A. Hansen

    1983-01-01

    Height growth of hybrid Populusand soil nitrogen concentration around Alnus glutinosa stems differed significantly both spatially and with the Alnus/Populus mixture in a short-rotation intensively cultured mixed planting. Populus height growth comparable to that obtained from optimal rates of...

  9. Growth and Physiological Response of Jatropha Interspecific Hybrid (Jatropha curcas x J. integerrima under Salt Stress

    Directory of Open Access Journals (Sweden)

    Dhimas Handhi Putranto

    2014-01-01

    Full Text Available Interspecific hybrid of Jatropha curcas x J. integerrima is expected to answer the low oil yield problem of Jatropha (Jatropha curcas L.. However, as a novel invention, research concerning on Jatropha interspecific hybrid is still limited especially in the aspect of its adaptability to unfavorable environment such as salt stress condition. It is interesting to know how Jatropha interspecific hybrid responses to salt stress condition due to the moderate salt tolerance ability of its mother plant (J. curcas L.. The objectives of this study were to compare the growth and physiological response of interspecific hybrid and non-hybrid Jatropha under salt stress. Three varieties of both interspecific hybrid and non-hybrid Jatropha seedling were exposed with 3 levels of sodium chloride treatment in Hoagland media solution which are 2.0 (control, 8.0, and 16.0 dS m-1 for 7 weeks. The parameters measured include plant height, number of leaves, shoot dry weight, specific leaf area, chlorophyll content (SPAD Index, leaf water potential, and leaf solute concentration. V2 (interspecific hybrid showed the highest potential as moderate salt tolerant variety among experimental Jatropha varieties due to its increasing trend of leaf number, dry weight, and total leaf area at moderate salinity level   (8 dS m-1. KUBP 35 and KUBP 40 showed the best growth performance under salt stress among experimental Jatropha varieties, but its potential to be moderate salt tolerant variety was still lower than V2 variety. The solute concentration, osmotic potential, and turgor potential of both interspecific hybrid (V2 and non-hybrid variety (KUBP 35 and KUBP 40 showed an increasing pattern which could be implied as an adaptive response to salt stress. This study has showed that Jatropha interspecific hybrid might have an adaptive physiological response to salt stress and could be considered as potential moderate salt tolerant variety under salt stress.

  10. Poplar MYB115 and MYB134 Transcription Factors Regulate Proanthocyanidin Synthesis and Structure.

    Science.gov (United States)

    James, Amy Midori; Ma, Dawei; Mellway, Robin; Gesell, Andreas; Yoshida, Kazuko; Walker, Vincent; Tran, Lan; Stewart, Don; Reichelt, Michael; Suvanto, Jussi; Salminen, Juha-Pekka; Gershenzon, Jonathan; Séguin, Armand; Constabel, C Peter

    2017-05-01

    The accumulation of proanthocyanidins is regulated by a complex of transcription factors composed of R2R3 MYB, basic helix-loop-helix, and WD40 proteins that activate the promoters of biosynthetic genes. In poplar (genus Populus), MYB134 is known to regulate proanthocyanidin biosynthesis by activating key flavonoid genes. Here, we characterize a second MYB regulator of proanthocyanidins, MYB115. Transgenic poplar overexpressing MYB115 showed a high-proanthocyanidin phenotype and reduced salicinoid accumulation, similar to the effects of MYB134 overexpression. Transcriptomic analysis of MYB115- and MYB134-overexpressing poplar plants identified a set of common up-regulated genes encoding proanthocyanidin biosynthetic enzymes and several novel uncharacterized MYB transcriptional repressors. Transient expression experiments demonstrated the capacity of both MYB134 and MYB115 to activate flavonoid promoters, but only in the presence of a basic helix-loop-helix cofactor. Yeast two-hybrid experiments confirmed the direct interaction of these transcription factors. The unexpected identification of dihydromyricetin in leaf extracts of both MYB115- and MYB134-overexpressing poplar led to the discovery of enhanced flavonoid B-ring hydroxylation and an increased proportion of prodelphinidins in proanthocyanidin of the transgenics. The dramatic hydroxylation phenotype of MYB115 overexpressors is likely due to the up-regulation of both flavonoid 3',5'-hydroxylases and cytochrome b5 Overall, this work provides new insight into the complexity of the gene regulatory network for proanthocyanidin synthesis in poplar. © 2017 American Society of Plant Biologists. All Rights Reserved.

  11. 西宁市宁张公路小叶杨的生长相关性分析%Growth Relevance Analysis of Chinese Poplar of Ningzhang Road of Xining City

    Institute of Scientific and Technical Information of China (English)

    樊桂芳

    2015-01-01

    significant difference was showed between predictions and observations. The correlation of crown breadth and diameter is significant. Therefore,the model can be used for predictions of crown breadth by diameter. The accurate growth simulation of Populus simonii may have important implications on creation of the best growing space,guarantee of the growth of trees,and management of road greening departments model as well as the crown growth quantity model,the precision is quite high,will be able accurately to forecast the Chinese poplar high growth the future tendency.

  12. 不同俄罗斯杨树新品种扦插苗的生长比较%Growth Comparison of Cuttings for Different New Varieties of Russian Poplars

    Institute of Scientific and Technical Information of China (English)

    梁立东; 李守忠; 杜鹏飞

    2013-01-01

    The rooting ,growth & biomass of introduced new varieties of Russian poplars (Populus schischkinii ,N12 , N2 ,N21 and SL-1) were compared systematically .Result shows that :there are significant differences in rooting rate ,seedling height ,ground diameter ,aboveground biomass ,belowground biomass & the biomass of the whole plant of hardwood cuttings .SL-1 is excellent in rooting rate ,seedling height ,ground diameter ,aboveground biomass ,be-lowground biomass & whole plant biomass of hardwood cuttings ,among which the seedling height ,ground diame-ter ,aboveground biomass ,belowground biomass & whole plant biomass are optimal than that of the control variety (Populus simonii × P .nigra);rooting ,growth & biomass of hardwood cuttings of SL-1 are the highest .%以引进的俄罗斯杨树新品种高加索白杨、N12、N2、N21和SL -1为参试品种,对其硬枝扦插苗生根、生长量和生物量进行了系统比较研究。结果表明:参试品种在硬枝扦插生根率、苗高、地径、地上生物量、地下生物量和全株生物量等方面存在显著差异,SL -1品种的硬枝扦插苗生根率、苗高、地径、地上生物量、地下生物量和全株生物量指标均优,其中苗高、地径、地上生物量、地下生物量和全株生物量等5项指标优于对照小黑杨品种,其硬枝扦插生根率、生长量和生物量最高。

  13. Chloroplast parameters differ in wild type and transgenic poplars overexpressing gsh1 in the cytosol.

    Science.gov (United States)

    Ivanova, L A; Ronzhina, D A; Ivanov, L A; Stroukova, L V; Peuke, A D; Rennenberg, H

    2009-07-01

    Poplar mutants overexpressing the bacterial genes gsh1 or gsh2 encoding the enzymes of glutathione biosynthesis are among the best-characterised transgenic plants. However, this characterisation originates exclusively from laboratory studies, and the performance of these mutants under field conditions is largely unknown. Here, we report a field experiment in which the wild-type poplar hybrid Populus tremula x P. alba and a transgenic line overexpressing the bacterial gene gsh1 encoding gamma-glutamylcysteine synthetase in the cytosol were grown for 3 years at a relatively clean (control) field site and a field site contaminated with heavy metals. Aboveground biomass accumulation was slightly smaller in transgenic compared to wild-type plants; soil contamination significantly decreased biomass accumulation in both wild-type and transgenic plants by more than 40%. Chloroplasts parameters, i.e., maximal diameter, projection area and perimeter, surface area and volume, surface/volume ratio and a two-dimensional form coefficient, were found to depend on plant type, leaf tissue and soil contamination. The greatest differences between wild and transgenic poplars were observed at the control site. Under these conditions, chloroplast sizes in palisade tissue of transgenic poplar significantly exceeded those of the wild type. In contrast to the wild type, palisade chloroplast volume exceeded that of spongy chloroplasts in transgenic poplars at both field sites. Chlorophyll content per chloroplast was the same in wild and transgenic poplars. Apparently, the increase in chloroplast volume was not connected to changes in the photosynthetic centres. Chloroplasts of transgenic poplar at the control site were more elongated in palisade cells and close to spherical in spongy mesophyll chloroplasts. At the contaminated site, palisade and spongy cell chloroplasts of leaves from transgenic trees and the wild type were the same shape. Transgenic poplars also had a smaller chloroplast

  14. Variation of physiological growth indices, biomass and dry matter yield in some maize hybrids

    Directory of Open Access Journals (Sweden)

    SHUKRI FETAHU

    2014-06-01

    Full Text Available In order to determine variation of physiological growth indices, biomass and dry matter yield, for six maize hybrids (MH, it was set up a field trial on randomized complete block design (RCDB, with three replications, with 6 MH: BC38W, BC408, ZP434, NSSC444, ESP500 and LUCE, during the years 2010 and 2011 (Y, at Experimental Farm (EF, Faculty of Agriculture and Veterinary in Prishtina, located in geographical position: N 42º 38'97" and E 21º 08'45" and 570 MASL. Growth rate, biomass and dry matter of maize performance are depending from specific characteristics: maize hybrids (MH, environmental condition (EC and cropping system (CS. Information on silage maize yield can help silage growers and users, to choose hybrids that best fit their needs. The physiological growth indices, biomass and dry matter yield, were conducted according to the formula: (MH-6 x Y-2 x P4 x R3 =144 combinations. Hybrid selection for a specific location, suitable for the agro-ecological condition is one of the essential principles for improving yield for silage or grain, without increasing of cost of maize production. Means results for evaluated maize hybrids and parameters were: Absolute growth rate (AGRµ=5.43, crop growth rate (CGRµ=30.98, total plant biomass (TPBµ=585.39 g plant-1 and total dry matter (TDMµ=22.52 ton ha-1.The aim of this study was to determine physiological growth indices, biomass and dry matter yield, in suitable agro-ecological conditions of Kosovo. The obtained results were with wide range variability and high significant differences between hybrids and years on the level P, lower than 0.01.

  15. Effect of technological parameters and wood properties on cutting power in plane milling of juvenile poplar wood

    Directory of Open Access Journals (Sweden)

    Barcík Štefan

    2008-10-01

    Full Text Available This paper presents the results of experimental measurements aimed at observing the effect of technological parameters (cutting speed vc and feed speed vf , type of wood (juvenile wood and mature wood andwood species (aspen Populus tremula, L. and hybrid poplar Populus x Euramericana „Serotina“ on cutting power during plane milling of poplar wood. The results showed the reduction of cutting power with the decrease of cutting speed and feed speed. Lower cutting power was also measured in milling hybrid poplar than in milling aspen. The test also confirmed the effect of different anatomical and chemical structure of juvenile wood in relation to mature wood on different physical and mechanical properties of such wood and hence also on the cutting power in processing juvenile wood.

  16. Ectomycorrhizal colonization and diversity in relation to tree biomass and nutrition in a plantation of transgenic poplars with modified lignin biosynthesis.

    Science.gov (United States)

    Danielsen, Lara; Lohaus, Gertrud; Sirrenberg, Anke; Karlovsky, Petr; Bastien, Catherine; Pilate, Gilles; Polle, Andrea

    2013-01-01

    Wood from biomass plantations with fast growing tree species such as poplars can be used as an alternative feedstock for production of biofuels. To facilitate utilization of lignocellulose for saccharification, transgenic poplars with modified or reduced lignin contents may be useful. However, the potential impact of poplars modified in the lignification pathway on ectomycorrhizal (EM) fungi, which play important roles for plant nutrition, is not known. The goal of this study was to investigate EM colonization and community composition in relation to biomass and nutrient status in wildtype (WT, Populus tremula × Populus alba) and transgenic poplar lines with suppressed activities of cinnamyl alcohol dehydrogenase, caffeate/5-hydroxyferulate O-methyltransferase, and cinnamoyl-CoA reductase in a biomass plantation. In different one-year-old poplar lines EM colonization varied from 58% to 86%, but the EM community composition of WT and transgenic poplars were indistinguishable. After two years, the colonization rate of all lines was increased to about 100%, but separation of EM communities between distinct transgenic poplar genotypes was observed. The differentiation of the EM assemblages was similar to that found between different genotypes of commercial clones of Populus × euramericana. The transgenic poplars exhibited significant growth and nutrient element differences in wood, with generally higher nutrient accumulation in stems of genotypes with lower than in those with higher biomass. A general linear mixed model simulated biomass of one-year-old poplar stems with high accuracy (adjusted R(2) = 97%) by two factors: EM colonization and inverse wood N concentration. These results imply a link between N allocation and EM colonization, which may be crucial for wood production in the establishment phase of poplar biomass plantations. Our data further support that multiple poplar genotypes regardless whether generated by transgenic approaches or conventional

  17. 虫害诱导的杨树化学物质对分月扇舟蛾生长发育的影响%Influence of pest induced poplar chemical substances on the growth and development of Clostera anastomosis

    Institute of Scientific and Technical Information of China (English)

    姚淑艳; 孟怡君

    2012-01-01

    As a new plant resistance type, induced resistance has a great potential in the feeding and egg laying prospects ofphytopha- gous insects. In this research, feeding selection behaviors of Clostera anastomos/s larvae to poplar leaves processed in different ways were observed indoor with a selective method. After 2-3 year larvae were fed with leaves damaged by insect pests for 48 hours, nutri- lional effect of the leaves damaged by insect pests was tested and the influences on the development period, pupa weight, emergence rate and other growth and development conditions of Clostera anastomosis larvae fed with the leaves damaged by insect pests was ana- lyzed. A biochemical method was used to detect the change of nutrient substances and secondary substances of the damage leaves. The results shown that the leaves damaged with insect pests had repellency against Clostera anastomosis; mechanical injury did not af- fect selectivity to hosts; and after Clostera anastomosis larvae eaten damaged leaves, the development period was prolonged, pupa weight, emergence rate, soluble sugar content were reduced, and the contents of tannin and tlavone were increased.%诱导抗性作为一种新的植物抗性类型,在防御植食性昆虫的取食和产卵方面具有很大的潜力。该项研究在室内采用选择性方法,观察了分月扇舟蛾幼虫对不同处理的杨树叶的取食选择行为。用虫害叶喂食2-3龄幼虫48h,测定其营养效应,分析了喂食虫害叶对分月扇舟蛾的幼虫发育历期、蛹重、羽化率等生长发育的影响。利用生化方法测定了杨树叶片虫害后营养物质和次生物质的变化。结果表明:虫害叶对分月扇舟蛾表现为忌避作用;机械损伤叶不影响对寄主的选择性。分月扇舟蛾取食虫害叶后幼虫的发育历期延长、蛹重增加、羽化率降低,可溶性糖含量下降,单宁和黄酮含量增加。

  18. Proteome Analysis of Poplar Seed Vigor.

    Science.gov (United States)

    Zhang, Hong; Wang, Wei-Qing; Liu, Shu-Jun; Møller, Ian Max; Song, Song-Quan

    2015-01-01

    Seed vigor is a complex property that determines the seed's potential for rapid uniform emergence and subsequent growth. However, the mechanism for change in seed vigor is poorly understood. The seeds of poplar (Populus × Canadensis Moench), which are short-lived, were stored at 30 °C and 75 ± 5% relative humidity for different periods of time (0-90 days) to obtain different vigor seeds (from 95 to 0% germination). With decreasing seed vigor, the temperature range of seed germination became narrower; the respiration rate of the seeds decreased markedly, while the relative electrolyte leakage increased markedly, both levelling off after 45 days. A total of 81 protein spots showed a significant change in abundance (≥ 1.5-fold, P seeds with different vigor. Of the identified 65 proteins, most belonged to the groups involved in metabolism (23%), protein synthesis and destination (22%), energy (18%), cell defense and rescue (17%), and storage protein (15%). These proteins accounted for 95% of all the identified proteins. During seed aging, 53 and 6 identified proteins consistently increased and decreased in abundance, respectively, and they were associated with metabolism (22%), protein synthesis and destination (22%), energy (19%), cell defense and rescue (19%), storage proteins (15%), and cell growth and structure (3%). These data show that the decrease in seed vigor (aging) is an energy-dependent process, which requires protein synthesis and degradation as well as cellular defense and rescue.

  19. Tungsten/Platinum Hybrid Nanowire Growth via Field Emission Using Nanorobotic Manipulation

    Directory of Open Access Journals (Sweden)

    Zhan Yang

    2011-01-01

    Full Text Available This paper reports tungsten-platinum hybrid nanowire growth via field emission, based on nanorobotic manipulation within a field emission scanning electron microscope (FESEM. A multiwalled carbon nanotube (MWCNT was used as the emitter, and a tungsten probe was used as the anode at the counterposition, by way of nanomanipulation. By independently employing trimethylcyclopentadienyl platinum (CpPtMe3 and tungsten hexacarbonyl (W(CO6 as precursors, the platinum nanowire grew on the tip of the MWCNT emitter. Tungsten nanowires then grew on the tip of the platinum nanowire. The hybrid nanowire length wascontrolled by nanomanipulation. Their purity was evaluated using energy-dispersive X-ray spectroscopy (EDS. Thus, it is possible to fabricate various metallic hybrid nanowires by changing the precursor materials. Hybrid nanowires have various applications in nanoelectronics, nanosensor devices, and nanomechanical systems.

  20. Stomatal factors and vulnerability of stem xylem to cavitation in poplars.

    Science.gov (United States)

    Arango-Velez, Adriana; Zwiazek, Janusz J; Thomas, Barb R; Tyree, Melvin T

    2011-10-01

    The relationships between the vulnerability of stem xylem to cavitation, stomatal conductance, stomatal density, and leaf and stem water potential were examined in six hybrid poplar (P38P38, Walker, Okanese, Northwest, Assiniboine and Berlin) and balsam poplar (Populus balsamifera) clones. Stem xylem cavitation resistance was examined with the Cavitron technique in well-watered plants grown in the greenhouse. To investigate stomatal responses to drought, plants were subjected to drought stress by withholding watering for 5 (mild drought) and 7 (severe drought) days and to stress recovery by rewatering severely stressed plants for 30 min and 2 days. The clones varied in stomatal sensitivity to drought and vulnerability to stem xylem cavitation. P38P38 reduced stomatal conductance in response to mild stress while the balsam poplar clone maintained high leaf stomatal conductance under more severe drought stress conditions. Differences between the severely stressed clones were also observed in leaf water potentials with no or relatively small decreases in Assiniboine, P38P38, Okanese and Walker. Vulnerability to drought-induced stem xylem embolism revealed that balsam poplar and Northwest clones reached loss of conductivity at lower stem water potentials compared with the remaining clones. There was a strong link between stem xylem resistance to cavitation and stomatal responsiveness to drought stress in balsam poplar and P38P38. However, the differences in stomatal responsiveness to mild drought suggest that other drought-resistant strategies may also play a key role in some clones of poplars exposed to drought stress. Copyright © Physiologia Plantarum 2011.

  1. Chlorine adlayer-templated growth of a hybrid inorganic-organic layered structure on Au(111)

    Science.gov (United States)

    Rzeźnicka, I. I.; Horino, H.; Yagyu, K.; Suzuki, T.; Kajimoto, S.; Fukumura, H.

    2016-10-01

    Growth of a hybrid inorganic-organic layered structure on the Au(111) surface using a one-step solution growth is reported. The hybrid structure is consist of 4,4‧-bipyridine [4,4‧-BiPyH2]2 + cations, Cl anions and Au adatoms, provided from substrate by means of the adsorbate-induced surface phase transition of a surface reconstruction. Its surface and bulk structures were characterized by scanning tunneling microscopy (STM), secondary ion mass spectrometry (SIMS), and Raman spectroscopy. STM results reveal growth of the first [4,4‧-BiPyH2]2 + layer on top of the p(√{ 3} ×√{ 3})" separators=", R 30 ° chlorine overlayer formed on the Au(111) surface. These two layers are found to provide a platform for a following three-dimensional growth facilitated by hydrogen bonding, aurophilic and π-π stacking interactions.

  2. Identification of CpTI Gene Integration for 2-year-old Transgenic Poplars at DNA Level

    Institute of Scientific and Technical Information of China (English)

    Zhang Qian; Lin Shanzhi; Lin Yuanzhen; Zhang Zhiyi; Liu Haijun; Zou Yening; Wang Zeliang

    2004-01-01

    The putative transgenic hybrid triploid poplars [(P. Tomentosa × P. Bolleana) × P. Tomentosa] with CpTI gene have been outplanted in test field for 2 years. Although the authors' previous studies have proved that they are highly resistant to 3 species of poplar-threatening insect pests and contain high content of CpTI protein in foliage, incorporation status of foreign CpTI gene in poplar genome is uncertain. In this present study, the incorporation of foreign CpTI gene in genome of 5 transgenic poplars was confirmed by PCR and Southern blotting analysis. DNA amplification showed that there were clear DNA bands of about 450bp specific to CpTI gene in transgenic lanes, while no corresponding band in non-transgenic lane was observed. Correspondingly, clear DNA hybridization signals and no signal were exhibited on film for DNA Southern blotting analysis in transgenic lanes and non-transgenic lane, respectively, which further confirmed the stable integration of foreign CpTI gene in genome of 2-year-old transgenic poplar.

  3. Plant protoplast fusion and growth of intergeneric hybrid cells.

    Science.gov (United States)

    Kao, K N; Constabel, F; Michayluk, M R; Gamborg, O L

    1974-01-01

    Interspecific and intergeneric fusions of plant protoplasts were induced by polyethylene glycol (PEG) 1540 or 4000. The frequency of heterokaryocyte formation (or rate of fusion) was much higher when PEG was eluted with a high pH-high Ca(2+) solution or a salt solution than when it was eluted with a protoplast culture medium. The frequency of heterokaryocyte formation was also affected by the types of enzymes used for wall degradation, duration of enzyme incubation and molality of the PEG solutions.The maximum frequency of heterokaryocyte formation was 23% for V. hajastana Grossh.-soybean (Glycine max L.) and barley (Hordeum vulgare L.)-soybean, 35% for pea (Pisum sativum L.)-soybean, 20% for pea-V. hajastana, 14% for corn (Zea mays L.)-soybean and 10% for V. villosa Roth-V. hajastana.40% of the barley-soybean, corn-soybean and pea-soybean heterokaryocytes divided at least once. Some divided many times and formed clusters of up to 100 cells in 2 weeks. The heterokaryocytes of soybean-V. hajastana, V. villosa-V. hajastana also divided. Of the PEG-treated protoplasts of N. langsdorffii and N. glauca 13.5% developed into tumor-like calli. The morphology of these calli was very much like that of the tumors produced on amphidiploid plants of N. langsdorffii x glauca.Nuclear staining indicated that heterokaryocytes of V. hajastana-soybean, pea-soybean, corn-soybean and barley-soybean could undergo mitosis. Nuclear divisions in a heterokaryocyte were usually synchronized or almost synchronized. Nuclear fusion and true hybrid formation usually occurred during the first mitotic division after protoplast fusion. A hybrid of barley-soybean in third cell division was observed. The frequency of heterokaryocytes which underwent nuclear fusion has not been determined. Multipole formation and chimeral cell colonies were also observed.

  4. [Canopy conductance characteristics of poplar in agroforestry system in west Liaoning Province of Northeast China].

    Science.gov (United States)

    Li, Zheng; Niu, Li-Hua; Yuan, Feng-Hui; Guan, De-Xin; Wang, An-Zhi; Jin, Chang-Jie; Wu, Jia-Bing

    2012-11-01

    By using Granier' s thermal dissipation probe, the sap flow of poplar in a poplar-maize agroforestry system in west Liaoning was continuously measured, and as well, the environmental factors such as air temperature, air humidity, net radiation, wind speed, soil temperature, and soil moisture content were synchronically measured. Based on the sap flow data, the canopy conductance of poplar was calculated with simplified Penman-Monteith equation. In the study area, the diurnal variation of poplar' s canopy conductance showed a "single peak" curve, whereas the seasonal variation showed a decreasing trend. There was a negative logarithm relationship between the canopy conductance and vapor pressure deficit, with the sensitivity of canopy conductance to vapor pressure deficit change decreased gradually from May to September. The canopy conductance had a positive relationship with solar radiation. In different months, the correlation degree of canopy conductance with environmental factors differed. The vapor pressure deficit in the whole growth period of poplar was the most significant environmental factor correlated with the canopy conductance.

  5. Obtaining the transgenic poplars with low lignin content through down-regulation of 4CL

    Institute of Scientific and Technical Information of China (English)

    JIA Caihong; ZHAO Huayan; WANG Hongzhi; XING Zhifeng; DU Kejiu; SONG Yanru; WEI Jianhua

    2004-01-01

    The antisense 4CL (4-coumarate: CoA ligase) gene was transformed into triploid Chinese white poplar (Populus tomentosa) mediated by Agrobacterium tumefaciens. PCR and Southern blot analysis indicated that antisense 4CL gene had been integrated into the genome of the transgenic Chinese white poplars. The antisense gene had also been expressed, which was indicated by RT-PCR and Western analysis. Klason lignin content assay showed that repression of 4CL expression could result in remarkable reduction of lignin content in transgenic poplars, with most reduction of 41.73% compared with that of wild type in this paper. But there is no significant difference in holocellulose content between trans- genic and wild poplars. We considered that 4CL might not be the metabolism control point between lignin and carbohy- drate biosynthesis. The stems of transgenic poplars displayed red-brown color with different levels after the bark was peeled, while those of untransformed plants were white. No visible differences in growth and development were observed between transgenic and wild plants. Wiesner reaction analysis of the transgenic plant stems with reduced lignin content exhibited red color, while that of untransformed plant was typically purple-red.

  6. Transcriptome Analysis of Poplar during Leaf Spot Infection with Sphaerulina spp.

    Science.gov (United States)

    Foster, Adam J; Pelletier, Gervais; Tanguay, Philippe; Séguin, Armand

    2015-01-01

    Diseases of poplar caused by the native fungal pathogen Sphaerulina musiva and related species are of growing concern, particularly with the increasing interest in intensive poplar plantations to meet growing energy demands. Sphaerulina musiva is able to cause infection on leaves, resulting in defoliation and canker formation on stems. To gain a greater understanding of the different responses of poplar species to infection caused by the naturally co-evolved Sphaerulina species, RNA-seq was conducted on leaves of Populus deltoides, P. balsamifera and P. tremuloides infected with S. musiva, S. populicola and a new undescribed species, Ston1, respectively. The experiment was designed to contain the pathogen in a laboratory environment, while replicating disease development in commercial plantations. Following inoculation, trees were monitored for disease symptoms, pathogen growth and host responses. Genes involved in phenylpropanoid, terpenoid and flavonoid biosynthesis were generally upregulated in P. balsamifera and P. tremuloides, while cell wall modification appears to play an important role in the defense of P. deltoides. Poplar defensive genes were expressed early in P. balsamifera and P. tremuloides, but their expression was delayed in P. deltoides, which correlated with the rate of disease symptoms development. Also, severe infection in P. balsamifera led to leaf abscission. This data gives an insight into the large differences in timing and expression of genes between poplar species being attacked by their associated Sphaerulina pathogen.

  7. Transcriptome Analysis of Poplar during Leaf Spot Infection with Sphaerulina spp.

    Directory of Open Access Journals (Sweden)

    Adam J Foster

    Full Text Available Diseases of poplar caused by the native fungal pathogen Sphaerulina musiva and related species are of growing concern, particularly with the increasing interest in intensive poplar plantations to meet growing energy demands. Sphaerulina musiva is able to cause infection on leaves, resulting in defoliation and canker formation on stems. To gain a greater understanding of the different responses of poplar species to infection caused by the naturally co-evolved Sphaerulina species, RNA-seq was conducted on leaves of Populus deltoides, P. balsamifera and P. tremuloides infected with S. musiva, S. populicola and a new undescribed species, Ston1, respectively. The experiment was designed to contain the pathogen in a laboratory environment, while replicating disease development in commercial plantations. Following inoculation, trees were monitored for disease symptoms, pathogen growth and host responses. Genes involved in phenylpropanoid, terpenoid and flavonoid biosynthesis were generally upregulated in P. balsamifera and P. tremuloides, while cell wall modification appears to play an important role in the defense of P. deltoides. Poplar defensive genes were expressed early in P. balsamifera and P. tremuloides, but their expression was delayed in P. deltoides, which correlated with the rate of disease symptoms development. Also, severe infection in P. balsamifera led to leaf abscission. This data gives an insight into the large differences in timing and expression of genes between poplar species being attacked by their associated Sphaerulina pathogen.

  8. EVALUATION OF HYBRIDIZATION BETWEEN PANGASIUS DJAMBAL BLEEKER 1846 AND PANGASIANODON HYPOPHTHALMUS (SAUVAGE 1878): BIOMETRIC CHARACTERIZATION AND GROWTH ANALYSIS

    OpenAIRE

    Rudhy Gustiano; Anang Hari Kristanto

    2007-01-01

    Possible use of pangasiid hybrids in aquaculture might generate potential impacts on wild populations. Therefore, rapid identification tools in the field such as growth rate are urgently needed. This study examines morphological characters and growth performance of P. djambal and P. hypophthalmus and their reciprocal hybrids. A detailed morphological study analysed 32 morphometric measurements and 5 meristic counts on hybrids of Pangasius djambal and P. hypophthalmus. Morphometric analysis an...

  9. Analyzing the impact of climate and management factors on the productivity and soil carbon sequestration of poplar plantations.

    Science.gov (United States)

    Wang, Dan; Fan, Jiazhi; Jing, Panpan; Cheng, Yong; Ruan, Honghua

    2016-01-01

    It is crucial to investigate how climate and management factors impact poplar plantation production and soil carbon sequestration interactively. We extracted above-ground net primary production (ANPP), climate and management factors from peer-reviewed journal articles and analyzed impact of management factor and climate on the mean annual increment (MAI) of poplar ANPP statistically. Previously validated mechanistic model (ED) is used to perform case simulations for managed poplar plantations under different harvesting rotations. The meta-analysis indicate that the dry matter MAI was 6.3 Mg ha(-1) yr(-1) (n=641, sd=4.9) globally, and 5.1 (n=292, sd=4.0), 8.1 (n=224, sd=4.7) and 4.4 Mg ha(-1) yr(-1) (n=125, sd=3.2) in Europe, the US and China, respectively. Poplar MAI showed a significant response to GDD, precipitation and planting density and formed a quadratic relationship with stand age. The low annual production for poplar globally was probably caused by suboptimal water availability, rotation length and planting density. SEM attributes the variance of poplar growth rate more to climate than to management effects. Case simulations indicated that longer rotation cycle significantly increased soil carbon storage. Findings of this work suggests that management factor of rotation cycle alone could have dramatic impact on the above ground growth, as well as on the soil carbon sequestration of poplar plantations and will be helpful to quantify the long-term carbon sequestration through short rotation plantation. The findings of this study are useful in guiding further research, policy and management decisions towards sustainable poplar plantations. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Controllable growth and characterizations of hybrid spiral-like atomically thin molybdenum disulfide

    Science.gov (United States)

    Hao, Song; Yang, Bingchu; Gao, Yongli

    2016-10-01

    Monolayer MoS2 is an emerging two-dimensional semiconductor with wide-ranging potential applications in novel electronic and optoelectronic devices. Here, we reported controlled vapor phase growth of hybrid spiral-like MoS2 crystals investigated by multiple means of X-Ray photoemission spectroscopy, scanning electron microscopy, atomic force microscopy, kelvin probe force microscopy, Raman and Photoluminescence techniques. Morphological characterizations reveal an intriguing hybrid spiral-like MoS2 feature whose lower planes are AB Bernal stacking and upper structure is spiral. We ascribe the hybrid spiral-like structure to a screw dislocation drive growth mechanism owing to lower supersaturation and layer-by-layer growth mode. In addition, the electrostatic properties of MoS2 microflakes with hybrid spiral structures are obvious inhomogeneous and dependent on morphology manifested by kelvin probe force microscopy. Our work deepens the understanding of growth mechanisms of CVD-grown MoS2, which is also adoptable to other TMDC materials.

  11. Larval and juvenile growth performance of Manila clam hybrids of two full-sib families

    Science.gov (United States)

    Huo, Zhongming; Yan, Xiwu; Zhao, Liqiang; Liang, Jian; Yang, Feng; Zhang, Guofan

    2015-06-01

    In order to determine whether growth performance could be improved by hybridizing full-sib families of Manila clam ( Ruditapes philippinarum), crosses between two full-sib families including self and reciprocal crosses were carried out. The effects of heterosis, combining ability and interaction on the growth of shell length were estimated. The results showed that the growth of hybrid larvae was intermediate between parents on days 6 and 9. Heterosis on shell length was observed, which varied at juvenile stage. The cross of ♂A × ♀B ( Hp varied between 10.41% and 68.27%) displayed larger heterosis than ♂B × ♀A ( Hp varied between 1.89% and 32.33%) did, suggesting that ♂A × ♀B was an ideal hatchery method of improving the growth performance of Manila clam. The variances of general combining ability (GCA), special combining ability (SCA) and interaction (I) were significant in shell length (P larvae and juveniles. The GCA for shell length of ♂A × ♀B was higher than that of ♂B × ♀A at both larval and juvenile stages. This confirmed that the cross between ♂A and ♀B showed great growth in shell length. In summary, the growth of Manila clam seeds could be improved by hybridizing selected parents from large numbers of full-sib families.

  12. Continuous steam hydrolysis of tulip poplar

    Energy Technology Data Exchange (ETDEWEB)

    Fieber, C.A.; Roberts, R.S.; Faass, G.S.; Muzzy, J.D.; Colcord, A.R.; Bery, M.K.

    1982-01-01

    The continuous hydrolysis of poplar chips by steam at 300-350 psi resulted in the separation of hemicellulose (I) cellulose and lignin components. The I fraction was readily depolymerised by steam to acetic acid, furfural, methanol, and xylose.

  13. Apoplast proteome reveals that extracellular matrix contributes to multistress response in poplar

    Directory of Open Access Journals (Sweden)

    Lawrence Amanda M

    2010-11-01

    Full Text Available Abstract Background Riverine ecosystems, highly sensitive to climate change and human activities, are characterized by rapid environmental change to fluctuating water levels and siltation, causing stress on their biological components. We have little understanding of mechanisms by which riverine plant species have developed adaptive strategies to cope with stress in dynamic environments while maintaining growth and development. Results We report that poplar (Populus spp. has evolved a systems level "stress proteome" in the leaf-stem-root apoplast continuum to counter biotic and abiotic factors. To obtain apoplast proteins from P. deltoides, we developed pressure-chamber and water-displacement methods for leaves and stems, respectively. Analyses of 303 proteins and corresponding transcripts coupled with controlled experiments and bioinformatics demonstrate that poplar depends on constitutive and inducible factors to deal with water, pathogen, and oxidative stress. However, each apoplast possessed a unique set of proteins, indicating that response to stress is partly compartmentalized. Apoplast proteins that are involved in glycolysis, fermentation, and catabolism of sucrose and starch appear to enable poplar to grow normally under water stress. Pathogenesis-related proteins mediating water and pathogen stress in apoplast were particularly abundant and effective in suppressing growth of the most prevalent poplar pathogen Melampsora. Unexpectedly, we found diverse peroxidases that appear to be involved in stress-induced cell wall modification in apoplast, particularly during the growing season. Poplar developed a robust antioxidative system to buffer oxidation in stem apoplast. Conclusion These findings suggest that multistress response in the apoplast constitutes an important adaptive trait for poplar to inhabit dynamic environments and is also a potential mechanism in other riverine plant species.

  14. Study on Poplar Industrialization in Jiangsu:(3)Conclusions and Recommendations on Poplar Industrialization Management

    Institute of Scientific and Technical Information of China (English)

    SHEN Wenxing; ZHOU Dingguo; XU Xinping

    2006-01-01

    This article concludes that the creation of a new industrial management,including the innovation of management institution,operation system,industrial policies and industrial technology,is a solution to the management optimization of the poplar industry.The further development of the poplar industry is beneficial to the sustainable development of the society,economy and ecological environment in Jiangsu province.

  15. Hybrid discrete-continuum model of tumor growth considering capillary points

    Institute of Scientific and Technical Information of China (English)

    吕杰; 许世雄; 姚伟; 周瑜; 龙泉

    2013-01-01

    A hybrid discrete-continuum model of tumor growth in the avascular phase considering capillary points is established. The influence of the position of capillary points on tumor growth is also studied by simulation. The results of the dynamic tumor growth and the distribution of oxygen, matrix-degrading enzymes, and extracellular matrix-concentration in the microenvironment with respect to time are shown by graphs. The relationships between different oxygenated environments and the numbers of surviving, dead, proliferative, and quiescent tumor cells are also investigated.

  16. Growth and Transfer of Seamless 3D Graphene-Nanotube Hybrids.

    Science.gov (United States)

    Kim, Nam Dong; Li, Yilun; Wang, Gunuk; Fan, Xiujun; Jiang, Jinlong; Li, Lei; Ji, Yongsung; Ruan, Gedeng; Hauge, Robert H; Tour, James M

    2016-02-10

    Seamlessly connected graphene and carbon nanotube hybrids (GCNTs) have great potential as carbon platform structures in electronics due to their high conductivity and high surface area. Here, we introduce a facile method for making patterned GCNTs and their intact transfer onto other substrates. The mechanism for selective growth of vertically aligned CNTs (VA-CNTs) on the patterned graphene is discussed. The complete transfer of the GCNT pattern onto other substrates is possible because of the mechanical strength of the GCNT hybrids. Electrical conductivity measurements of the transferred GCNT structures show Ohmic contact through the VA-CNTs to graphene--evidence of its integrity after the transfer process.

  17. Comparative growth and viability of hybrids between two populations of Chinese shrimp (Fennropenaeus chinensis)

    Institute of Scientific and Technical Information of China (English)

    TIAN Yi; KONG Jie; YANG Cuihua

    2006-01-01

    Fenneropenaeus chinensis is confined to the Yellow Sea and Bohai Sea in China and the West Coast of the Korean Peninsula. Intra- and intercross populations were produced between Rushany (YP) and Korean (KN) populations. Seven traits were recorded. The heterosis of hybrids was computed and comparison between treatments was performed by ANOVA. At the fourth month after post-larvae, six indexes of growth trait and viability showed a range of heterosis, ranging from 0.514% to 14.950%. At the fifth month after post-larvae, six indexes of growth trait and viability ranged from -9.000% to 19.090%. The negative heterosis was observed in CL, HST and viability. The heterosis of KN♀×YP♂ tended generally to increase as the age of the Chinese shrimp increased while the heterosis of YP♀×KN♂ tended to decrease. The results indicated that the viability of reciprocal hybrids were not significantly different (P>0.05) from their parents during the experiment. The result of ANOVA indicated that the F1 hybrids were significantly different (P<0.05) in WST and TW at the fourth month. The multiple comparisons of LSD test indicated that the hybrids of YP♀×KN♂ were significantly different (P<0.05) from their parents in TW. The hybrids of YP♀×KN♂ were significantly different (P<0.05) from the other three combinations in WST. At the fifth months, the F1 hybrids had significant difference (P<0.05) in body weight while other traits showed no significant differences (P>0.05) from their parents. The multiple comparisons of LSD test indicated that the hybrids of KN♀×YP♂ were significantly different (P<0.05) from the KN parents in TW. The results indicate that in experimental conditions, the F1 hybrids created from two populations of Chinese shrimp showed a certain level of heterosis for growth performance and viability. The crossing scheme may improve growth performance and viability in Chinese shrimp, but the improvement may be limited because effective

  18. Growth and nutritional evaluation of napier grass hybrids as forage for ruminants

    Directory of Open Access Journals (Sweden)

    Brian Turano

    2016-09-01

    Full Text Available Napier grass is a perennial, tropical C-4 grass that can produce large amounts of forage. However, low temperatures and drought stress limit its productivity and nutritive value as a forage. To overcome these limitations, pearl millet × napier grass hybrids (PMN were developed. It was hypothesized that PMN hybrids were more drought-tolerant, produced higher yields, and had higher nutritive value than napier grass varieties. The yield and nutritive value of 4 napier grass varieties (Bana grass, Mott, MB4 and N51 and 4 PMN hybrids (PMN2, PMN3, 5344 and 4604 were determined with or without irrigation in a strip plot design in Hawaii. Hybrid PMN3 outperformed napier grass varieties and the other hybrids for yield, while 5344 showed higher nutritional content and digestibility than most other grasses. Dry matter yields during the 110-day study period ranged from 10.3 to 32.1 t/ha without irrigation and 19.6 to 55.8 t/ha with irrigation, indicating that moisture stress was limiting performance in raingrown pastures. Only hybrids PMN3 and PMN2 and variety MB4 showed significant growth responses to irrigation. Further work is needed to evaluate the hybrids in a range of environments over much longer periods to determine if these preliminary results can be reproduced over the long term. Similarly, feeding studies with animals are needed to determine if the in vitro data for digestibility are reflected in superior performance for the promising hybrids.Keywords: Biomass, cattle, in vitro digestion, nutrient content, Pennisetum, tropical grasses.DOI: 10.17138/TGFT(4168-178

  19. Hybridization between Yellowstone cutthroat trout and rainbow trout alters the expression of muscle growth-related genes and their relationships with growth patterns

    Science.gov (United States)

    Ostberg, Carl O.; Chase, Dorothy M.; Hauser, Lorenz

    2015-01-01

    Hybridization creates novel gene combinations that may generate important evolutionary novelty, but may also reduce existing adaptation by interrupting inherent biological processes, such as genotype-environment interactions. Hybridization often causes substantial change in patterns of gene expression, which, in turn, may cause phenotypic change. Rainbow trout (Oncorhynchus mykiss) and cutthroat trout (O. clarkii) produce viable hybrids in the wild, and introgressive hybridization with introduced rainbow trout is a major conservation concern for native cutthroat trout. The two species differ in body shape, which is likely an evolutionary adaptation to their native environments, and their hybrids tend to show intermediate morphology. The characterization of gene expression patterns may provide insights on the genetic basis of hybrid and parental morphologies, as well as on the ecological performance of hybrids in the wild. Here, we evaluated the expression of eight growth-related genes (MSTN-1a, MSTN-1b, MyoD1a, MyoD1b, MRF-4, IGF-1, IGF-2, and CAST-L) and the relationship of these genes with growth traits (length, weight, and condition factor) in six line crosses: both parental species, both reciprocal F1 hybrids, and both first-generation backcrosses (F1 x rainbow trout and F1 x cutthroat trout). Four of these genes were differentially expressed among rainbow, cutthroat, and their hybrids. Transcript abundance was significantly correlated with growth traits across the parent species, but not across hybrids. Our findings suggest that rainbow and cutthroat trout exhibit differences in muscle growth regulation, that transcriptional networks may be modified by hybridization, and that hybridization disrupts intrinsic relationships between gene expression and growth patterns that may be functionally important for phenotypic adaptations.

  20. Hybridization between Yellowstone Cutthroat Trout and Rainbow Trout Alters the Expression of Muscle Growth-Related Genes and Their Relationships with Growth Patterns.

    Directory of Open Access Journals (Sweden)

    Carl O Ostberg

    Full Text Available Hybridization creates novel gene combinations that may generate important evolutionary novelty, but may also reduce existing adaptation by interrupting inherent biological processes, such as genotype-environment interactions. Hybridization often causes substantial change in patterns of gene expression, which, in turn, may cause phenotypic change. Rainbow trout (Oncorhynchus mykiss and cutthroat trout (O. clarkii produce viable hybrids in the wild, and introgressive hybridization with introduced rainbow trout is a major conservation concern for native cutthroat trout. The two species differ in body shape, which is likely an evolutionary adaptation to their native environments, and their hybrids tend to show intermediate morphology. The characterization of gene expression patterns may provide insights on the genetic basis of hybrid and parental morphologies, as well as on the ecological performance of hybrids in the wild. Here, we evaluated the expression of eight growth-related genes (MSTN-1a, MSTN-1b, MyoD1a, MyoD1b, MRF-4, IGF-1, IGF-2, and CAST-L and the relationship of these genes with growth traits (length, weight, and condition factor in six line crosses: both parental species, both reciprocal F1 hybrids, and both first-generation backcrosses (F1 x rainbow trout and F1 x cutthroat trout. Four of these genes were differentially expressed among rainbow, cutthroat, and their hybrids. Transcript abundance was significantly correlated with growth traits across the parent species, but not across hybrids. Our findings suggest that rainbow and cutthroat trout exhibit differences in muscle growth regulation, that transcriptional networks may be modified by hybridization, and that hybridization disrupts intrinsic relationships between gene expression and growth patterns that may be functionally important for phenotypic adaptations.

  1. Hybridization between Yellowstone Cutthroat Trout and Rainbow Trout Alters the Expression of Muscle Growth-Related Genes and Their Relationships with Growth Patterns.

    Science.gov (United States)

    Ostberg, Carl O; Chase, Dorothy M; Hauser, Lorenz

    2015-01-01

    Hybridization creates novel gene combinations that may generate important evolutionary novelty, but may also reduce existing adaptation by interrupting inherent biological processes, such as genotype-environment interactions. Hybridization often causes substantial change in patterns of gene expression, which, in turn, may cause phenotypic change. Rainbow trout (Oncorhynchus mykiss) and cutthroat trout (O. clarkii) produce viable hybrids in the wild, and introgressive hybridization with introduced rainbow trout is a major conservation concern for native cutthroat trout. The two species differ in body shape, which is likely an evolutionary adaptation to their native environments, and their hybrids tend to show intermediate morphology. The characterization of gene expression patterns may provide insights on the genetic basis of hybrid and parental morphologies, as well as on the ecological performance of hybrids in the wild. Here, we evaluated the expression of eight growth-related genes (MSTN-1a, MSTN-1b, MyoD1a, MyoD1b, MRF-4, IGF-1, IGF-2, and CAST-L) and the relationship of these genes with growth traits (length, weight, and condition factor) in six line crosses: both parental species, both reciprocal F1 hybrids, and both first-generation backcrosses (F1 x rainbow trout and F1 x cutthroat trout). Four of these genes were differentially expressed among rainbow, cutthroat, and their hybrids. Transcript abundance was significantly correlated with growth traits across the parent species, but not across hybrids. Our findings suggest that rainbow and cutthroat trout exhibit differences in muscle growth regulation, that transcriptional networks may be modified by hybridization, and that hybridization disrupts intrinsic relationships between gene expression and growth patterns that may be functionally important for phenotypic adaptations.

  2. Nucleotide diversity among natural populations of a North American poplar (Populus balsamifera, Salicaceae).

    Science.gov (United States)

    Breen, Amy L; Glenn, Elise; Yeager, Adam; Olson, Matthew S

    2009-01-01

    Poplars (Populus spp.) comprise an important component of circumpolar boreal forest ecosystems and are the model species for tree genomics. In this study, we surveyed genetic variation and population differentiation in three nuclear genes among populations of balsam poplar (Populus balsamifera) in North America. We examined nucleotide sequence variation in alcohol dehydrogenase 1 (Adh1) and glyceraldehyde 3-phosphate dehydrogenase (G3pdh), two well-studied nuclear loci in plants, and abscisic acid insensitivity 1B (ABI1B), a locus coincident with timing of seasonal dormancy in quantitative trait locus (QTL) studies of hybrid poplars. We compared estimates of baseline population genetic parameters for these loci with those obtained in studies of other poplar species, particularly European aspen (Populus tremula). Average pairwise nucleotide diversity (pi(tot) = 0.00216-0.00353) was equivalent to that in Populus trichocarpa, but markedly less than that in P. tremula. Elevated levels of population structure were observed in ABI1B between the northern and southern regions (F(CT) = 0.184, P boreal plant species.

  3. Effects of Direct Application of Fertilizers and Hydrogel on the Establishment of Poplar Cuttings

    Directory of Open Access Journals (Sweden)

    Henrik Böhlenius

    2014-12-01

    Full Text Available The aim of poplar plantations is to achieve high biomass production over a short rotation period. This requires low mortality and fast development of the transplants. The experiment described in this paper examines methods aimed at enhancing survival and development of Populus trichocarpa plants by application of fertilizers, a hydrogel or a combination of both to dormant cuttings just before planting. The experiment was carried out at two agricultural sites with different soil characteristics, a loamy sand and a silty loam. It was demonstrated that none of the treatments influenced survival or early growth at the silty loam soil site, and plant development was delayed by the solid fertilizer. At the site with loamy sand, the solid fertilizer negatively affected both survival and early growth. Hydrogel and the combination of hydrogel and the solid fertilizer also hampered early growth. Overall, treatments of poplar cuttings with hydrogel or fertilizers alone, or in combination, may not be a method to reduce poplar cutting mortality or to enhance early plant development on agricultural land. However, our results demonstrate that establishing poplar with cuttings as transplants can be used on both loamy sand and silty loam soils.

  4. Simulation of hydrogen bubble growth in tungsten by a hybrid model

    Science.gov (United States)

    Sang, Chaofeng; Sun, Jizhong; Bonnin, Xavier; Wang, L.; Wang, Dezhen

    2015-08-01

    A two dimensional hybrid code (HIIPC-MC) joining rate-theory and Monte Carlo (MC) methods is developed in this work. We evaluate the cascade-coalescence mechanism contribution to the bubble growth by MC. First, effects of the starting radius and solute deuterium concentration on the bubble growth are studied; then the impacts of the wall temperature and implantation ion flux on the bubble growth are assessed. The simulation indicates that the migration-coalescence of the bubbles and the high pressure inside the bubbles are the main driving forces for the bubble growth, and that neglect of the migration and coalescence would lead to an underestimation of the bubble growth or blistering.

  5. Simulation of hydrogen bubble growth in tungsten by a hybrid model

    Energy Technology Data Exchange (ETDEWEB)

    Sang, Chaofeng, E-mail: sang@dlut.edu.cn [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China); Sun, Jizhong [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China); Bonnin, Xavier [LSPM-CNRS, Université Paris 13, Sorbonne Paris Cité, Villetaneuse 93430 (France); Wang, L. [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China); Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Wang, Dezhen, E-mail: wangdez@dlut.edu.cn [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China)

    2015-08-15

    A two dimensional hybrid code (HIIPC-MC) joining rate-theory and Monte Carlo (MC) methods is developed in this work. We evaluate the cascade-coalescence mechanism contribution to the bubble growth by MC. First, effects of the starting radius and solute deuterium concentration on the bubble growth are studied; then the impacts of the wall temperature and implantation ion flux on the bubble growth are assessed. The simulation indicates that the migration-coalescence of the bubbles and the high pressure inside the bubbles are the main driving forces for the bubble growth, and that neglect of the migration and coalescence would lead to an underestimation of the bubble growth or blistering.

  6. CVD growth of graphene under exfoliated hexagonal boron nitride for vertical hybrid structures

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Min [SKKU Advanced Institute of Nanotechnology (SAINT) (Korea, Republic of); Center for Human Interface Nanotechnology (HINT) (Korea, Republic of); Jang, Sung Kyu [SKKU Advanced Institute of Nanotechnology (SAINT) (Korea, Republic of); Song, Young Jae [SKKU Advanced Institute of Nanotechnology (SAINT) (Korea, Republic of); Department of Physics, Sungkyunkwan University (SKKU), Suwon 440-746 (Korea, Republic of); Lee, Sungjoo, E-mail: leesj@skku.edu [SKKU Advanced Institute of Nanotechnology (SAINT) (Korea, Republic of); Center for Human Interface Nanotechnology (HINT) (Korea, Republic of); College of Information and Communication Engineering, Sungkyunkwan University (SKKU), Suwon 440-746 (Korea, Republic of)

    2015-01-15

    Graphical abstract: We have demonstrated a novel yet simple method for fabricating graphene-based vertical hybrid structures by performing the CVD growth of graphene at an h-BN/Cu interface. Our systematic Raman measurements combined with plasma etching process indicate that a graphene film is grown under exfoliated h-BN rather than on its top surface, and that an h-BN/graphene vertical hybrid structure has been fabricated. Electrical transport measurements of this h-BN/graphene, transferred on SiO2, show the carrier mobility up to approximately 2250 cm{sup 2} V{sup −1} s{sup −1}. The developed method would enable the exploration of the possibility of novel hybrid structure integration with two-dimensional material systems. - Abstract: We have demonstrated a novel yet simple method for fabricating graphene-based vertical hybrid structures by performing the CVD growth of graphene at an h-BN/Cu interface. Our systematic Raman measurements combined with plasma etching process indicate that a graphene film is grown under exfoliated h-BN rather than on its top surface, and that an h-BN/graphene vertical hybrid structure has been fabricated. Electrical transport measurements of this h-BN/graphene, transferred on SiO{sub 2}, show the carrier mobility up to approximately 2250 cm{sup 2} V{sup −1} s{sup −1}. The developed method would enable the exploration of the possibility of novel hybrid structure integration with two-dimensional material systems.

  7. Modeling plasma-assisted growth of graphene-carbon nanotube hybrid

    Science.gov (United States)

    Tewari, Aarti

    2016-08-01

    A theoretical model describing the growth of graphene-CNT hybrid in a plasma medium is presented. Using the model, the growth of carbon nanotube (CNT) on a catalyst particle and thereafter the growth of the graphene on the CNT is studied under the purview of plasma sheath and number density kinetics of different plasma species. It is found that the plasma parameter such as ion density; gas ratios and process parameter such as source power affect the CNT and graphene dimensions. The variation in growth rates of graphene and CNT under different plasma power, gas ratios, and ion densities is analyzed. Based on the results obtained, it can be concluded that higher hydrocarbon ion densities and gas ratios of hydrocarbon to hydrogen favor the growth of taller CNTs and graphene, respectively. In addition, the CNT tip radius reduces with hydrogen ion density and higher plasma power favors graphene with lesser thickness. The present study can help in better understanding of the graphene-CNT hybrid growth in a plasma medium.

  8. Effects of prey density on the growth and survival of hybrid snakehead larvae

    Institute of Scientific and Technical Information of China (English)

    Wenkui LIU; Qixue FAN; Bangke ZHU; Haiming DU; Xigang FENG

    2008-01-01

    The effects of prey density (0.1, 0.3, 1, 3 and snakehead (Channa argus × C. maculate) larvae were investigated. The larvae were divided into three groups with different body lengths of 0.68 cm, 1.50 cm and 3.20 cm, respectively. The growth of the hybrid snake-head larvae in all three groups increased with prey growth rate (SGR) was the highest when the prey density early development stage) decreased, while no significant change was observed in those of Group Ⅱ and Group Ⅲ. The survival rates of hybrid snakehead larvae in all three groups were high (91.11%-100%) and not significantly affected by the prey densities except in Group Ⅰ with the significantly lower than the others. Body size was not sensitive to prey density. The optimum prey density was confirmed at 1 prey·mL-1 in all the treatments.

  9. Arbuscular mycorrhizal fungi differentially affect the response to high zinc concentrations of two registered poplar clones

    Energy Technology Data Exchange (ETDEWEB)

    Lingua, Guido [Dipartimento di Scienze dell' Ambiente e della Vita, Universita del Piemonte Orientale ' Amedeo Avogadro' , Via Bellini 25/G, I-15100 Alessandria (Italy)], E-mail: guido.lingua@mfn.unipmn.it; Franchin, Cinzia [Dipartimento di Biologia evoluzionistica sperimentale, Universita di Bologna, Via Irnerio 42, I-40126 Bologna (Italy); Todeschini, Valeria [Dipartimento di Scienze dell' Ambiente e della Vita, Universita del Piemonte Orientale ' Amedeo Avogadro' , Via Bellini 25/G, I-15100 Alessandria (Italy); Castiglione, Stefano [Dipartimento di Biologia, Universita di Milano, Via Celoria 25, I-20100 Milano (Italy); Biondi, Stefania [Dipartimento di Biologia evoluzionistica sperimentale, Universita di Bologna, Via Irnerio 42, I-40126 Bologna (Italy); Burlando, Bruno [Dipartimento di Scienze dell' Ambiente e della Vita, Universita del Piemonte Orientale ' Amedeo Avogadro' , Via Bellini 25/G, I-15100 Alessandria (Italy); Parravicini, Valerio [Dipartimento di Biologia, Universita di Milano, Via Celoria 25, I-20100 Milano (Italy); Torrigiani, Patrizia [Dipartimento di Biologia evoluzionistica sperimentale, Universita di Bologna, Via Irnerio 42, I-40126 Bologna (Italy); Berta, Graziella [Dipartimento di Scienze dell' Ambiente e della Vita, Universita del Piemonte Orientale ' Amedeo Avogadro' , Via Bellini 25/G, I-15100 Alessandria (Italy)

    2008-05-15

    The effects of a high concentration of zinc on two registered clones of poplar (Populus alba Villafranca and Populus nigra Jean Pourtet), inoculated or not with two arbuscular mycorrhizal fungi (Glomus mosseae or Glomus intraradices) before transplanting them into polluted soil, were investigated, with special regard to the extent of root colonization by the fungi, plant growth, metal accumulation in the different plant organs, and leaf polyamine concentration. Zinc accumulation was lower in Jean Pourtet than in Villafranca poplars, and it was mainly translocated to the leaves; the metal inhibited mycorrhizal colonization, compromised plant growth, and, in Villafranca, altered the putrescine profile in the leaves. Most of these effects were reversed or reduced in plants pre-inoculated with G. mosseae. Results indicate that poplars are suitable for phytoremediation purposes, confirming that mycorrhizal fungi can be useful for phytoremediation, and underscore the importance of appropriate combinations of plant genotypes and fungal symbionts. - Inoculation with arbuscular mycorrhizal fungi can improve poplar tolerance to heavy metals in phytoremediation programmes.

  10. Dynamic nanocrystal response and high temperature growth of carbon nanotube-ferroelectric hybrid nanostructure

    Science.gov (United States)

    Kumar, Ashok; Scott, J. F.; Katiyar, R. S.

    2013-12-01

    A long standing problem related to the capping of carbon nanotubes (CNT) by inorganic materials at high temperature has been solved. In situ dynamic response of Pb(Zr0.52Ti0.48)O3 (PZT) nanocrystals attached to the wings of the outer surface of PZT/CNT hybrid-nanostructure has been demonstrated under a constant-energy high-resolution transmission electron microscopy (HRTEM) e-beam. PZT nanocrystals revealed that the crystal orientations, positions, faces, and hopping states change with time. HRTEM study has been performed to investigate the microstructure of hybrid nanostructures and nanosize polycrystal trapped across the wings. Raman spectroscopy was utilized to investigate the local structures, defects, crystal qualities and temperature dependent growth and degradation of hybrid nanostructures. Raman spectra indicate that MWCNT and PZT/MWCNT/n-Si possess good quality of CNT before and after PZT deposition until 650 °C. The monoclinic Cc/Cm phase of PZT which is optimum in piezoelectric properties was prominent in the hybrid structure and should be useful for device applications. An unusual hexagonal faceting oscillation of the nano-crystal perimeter on a 10-30 s period is also observed.A long standing problem related to the capping of carbon nanotubes (CNT) by inorganic materials at high temperature has been solved. In situ dynamic response of Pb(Zr0.52Ti0.48)O3 (PZT) nanocrystals attached to the wings of the outer surface of PZT/CNT hybrid-nanostructure has been demonstrated under a constant-energy high-resolution transmission electron microscopy (HRTEM) e-beam. PZT nanocrystals revealed that the crystal orientations, positions, faces, and hopping states change with time. HRTEM study has been performed to investigate the microstructure of hybrid nanostructures and nanosize polycrystal trapped across the wings. Raman spectroscopy was utilized to investigate the local structures, defects, crystal qualities and temperature dependent growth and degradation of

  11. Reduced growth in hybrid tilapia ( Oreochromis mossambicus ×O. Niloticus) at intermediate stocking density

    Science.gov (United States)

    Wang, Yan; Cui, Yi-Bo; Yang, Yun-Xia; Cai, Fa-Sheng

    2002-12-01

    Hybrid tilapia were reared at densities of 1, 5 or 10 fish per tank for four weeks. Mortality was 0 at 1 and 10 fish per tank, but was 25% at 5 fish per tank. Specific growth rate was highest at 1 fish per tank, and lowest at 5 fish per tank. The lower growth rate at the intermediate stocking density was associated with reduced feed efficiency, but there was no reduction in feed intake or digestibility. The results suggested increased metabolic cost caused by aggressive behaviour at intermediate stocking density, which can be suppressed by a further increase in density.

  12. REDUCED GROWTH IN HYBRID TILAPIA (OREOCHROMIS MOSSAMBICUS×O. NILOTICUS) AT INTERMEDIATE STOCKING DENSITY

    Institute of Scientific and Technical Information of China (English)

    王岩; 崔奕波; 杨云霞; 蔡发盛

    2002-01-01

    Hybrid tilapia were reared at densities of 1, 5 or 10 fish per tank for four weeks. Mortality was 0 at 1 and 10 fish per tank, but was 25% at 5 fish per tank. Specific growth rate was highest at 1 fish per tank, and lowest at 5 fish per tank. The lower growth rate at the intermediate stocking density was associated with reduced feed efficiency, but there was no reduction in feed intake or digestibility. The results suggested increased metabolic cost caused by aggressive behaviour at intermediate stocking density, which can be suppressed by a further increase in density.

  13. Regulation of endocrine and paracrine sources of insulin-like growth factors and growth hormone receptor during compensatory growth in hybrid striped bass (Morone chrysops x Morone saxatilis)

    DEFF Research Database (Denmark)

    Picha, Matthew E; Turano, Marc J; Tipsmark, Christian K;

    2008-01-01

    relieved, renders a subsequent phase of CG. The catabolic state was characterized by depressed levels of hepatic Type I and II GH receptor (Ghr1, Ghr2) and insulin-like growth factor-I (Igf-I) mRNA, along with considerable decreases in plasma IGF-I. The state of catabolism also resulted in significant......Compensatory growth (CG) is a period of growth acceleration that exceeds normal rates after animals are alleviated of certain growth-stunting conditions. In hybrid striped bass (HSB, Morone chrysops x M. saxatilis), 3 weeks of complete feed restriction results in a catabolic state that, when...... declines in hepatic Igf-II mRNA and in circulating 40kDa IGF binding protein (IGFBP). Skeletal muscle expression of Ghr2 mRNA was significantly increased. Upon realimentation, specific growth rates (SGR) were significantly higher than sized-matched controls, indicating a period of CG. Hepatic Ghr1, Ghr2...

  14. Forest biorefinery: Potential of poplar phytochemicals as value-added co-products.

    Science.gov (United States)

    Devappa, Rakshit K; Rakshit, Sudip K; Dekker, Robert F H

    2015-11-01

    The global forestry industry after experiencing a market downturn during the past decade has now aimed its vision towards the integrated biorefinery. New business models and strategies are constantly being explored to re-invent the global wood and pulp/paper industry through sustainable resource exploitation. The goal is to produce diversified, innovative and revenue generating product lines using on-site bioresources (wood and tree residues). The most popular product lines are generally produced from wood fibers (biofuels, pulp/paper, biomaterials, and bio/chemicals). However, the bark and other tree residues like foliage that constitute forest wastes, still remain largely an underexploited resource from which extractives and phytochemicals can be harnessed as by-products (biopharmaceuticals, food additives and nutraceuticals, biopesticides, cosmetics). Commercially, Populus (poplar) tree species including hybrid varieties are cultivated as a fast growing bioenergy crop, but can also be utilized to produce bio-based chemicals. This review identifies and underlines the potential of natural products (phytochemicals) from Populus species that could lead to new business ventures in biorefineries and contribute to the bioeconomy. In brief, this review highlights the importance of by-products/co-products in forest industries, methods that can be employed to extract and purify poplar phytochemicals, the potential pharmaceutical and other uses of >160 phytochemicals identified from poplar species - their chemical structures, properties and bioactivities, the challenges and limitations of utilizing poplar phytochemicals, and potential commercial opportunities. Finally, the overall discussion and conclusion are made considering the recent biotechnological advances in phytochemical research to indicate the areas for future commercial applications from poplar tree species. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

  15. Degradation of poplar bark by Panaeolus

    Energy Technology Data Exchange (ETDEWEB)

    Scurti, J.C.; Fiussello, N.; Gullino, M.L.; Ferrara, R.

    1978-01-01

    Pure cultures of 41 strains of Paneolus were tested for their ability to break down poplar bark with a view to their possible use for biodegradation of this waste product of paper manufacture. Most strains were able to grow (slowly) on sterilized poplar bark and showed high ligninolytic activity. Some strains also showed cellulolytic action. Almost all the strains showed phenol-oxidase activity, but there was no correlation between lignin decomposition and phenol-oxidase activity. The amounts of bark degraded by the fungi were relatively small (3.2 - 13.0% loss of dry weight after six months incubation).

  16. Wastewater and sewage sludge application to willows and poplars grown in lysimeters-Plant response and treatment efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Dimitriou, I.; Aronsson, P. [Department of Crop Production Ecology, Swedish University of Agricultural Sciences (SLU), Ecology building, P.O. Box 7043, SE 750 07 Uppsala (Sweden)

    2011-01-15

    Adding nutrient-rich residues such as municipal wastewater and sludge to willow and poplar short-rotation coppice gives more cost-effective and sustainable cultivation, but leaching to groundwater and disturbance to plant growth must be avoided. The effects of adding municipal wastewater irrigation to willows and poplars and sewage sludge to willows were compared in a two-year experiment. Wastewater irrigation enhanced plant growth. Near-zero nitrate-N concentrations occurred in drainage water when the root system of both species was well-established. The ability to retain N and P was satisfactory when poplars and willows were irrigated with wastewater. Thus relatively high additions of N and P with wastewater will probably not contaminate groundwater, but potential P leaching should not be underestimated. The same applies for sewage sludge applications to willow. (author)

  17. Dynamic nanocrystal response and high temperature growth of carbon nanotube-ferroelectric hybrid nanostructure.

    Science.gov (United States)

    Kumar, Ashok; Scott, J F; Katiyar, R S

    2014-01-21

    A long standing problem related to the capping of carbon nanotubes (CNT) by inorganic materials at high temperature has been solved. In situ dynamic response of Pb(Zr0.52Ti0.48)O3 (PZT) nanocrystals attached to the wings of the outer surface of PZT/CNT hybrid-nanostructure has been demonstrated under a constant-energy high-resolution transmission electron microscopy (HRTEM) e-beam. PZT nanocrystals revealed that the crystal orientations, positions, faces, and hopping states change with time. HRTEM study has been performed to investigate the microstructure of hybrid nanostructures and nanosize polycrystal trapped across the wings. Raman spectroscopy was utilized to investigate the local structures, defects, crystal qualities and temperature dependent growth and degradation of hybrid nanostructures. Raman spectra indicate that MWCNT and PZT/MWCNT/n-Si possess good quality of CNT before and after PZT deposition until 650 °C. The monoclinic Cc/Cm phase of PZT which is optimum in piezoelectric properties was prominent in the hybrid structure and should be useful for device applications. An unusual hexagonal faceting oscillation of the nano-crystal perimeter on a 10-30 s period is also observed.

  18. Poplar trees for phytoremediation of high levels of nitrate and applications in bioenergy.

    Science.gov (United States)

    Castro-Rodríguez, Vanessa; García-Gutiérrez, Angel; Canales, Javier; Cañas, Rafael A; Kirby, Edward G; Avila, Concepción; Cánovas, Francisco M

    2016-01-01

    The utilization of high amounts of nitrate fertilizers for crop yield leads to nitrate pollution of ground and surface waters. In this study, we report the assimilation and utilization of nitrate luxuriant levels, 20 times more than the highest N fertilizer application in Europe, by transgenic poplars overexpressing a cytosolic glutamine synthetase (GS1). In comparison with the wild-type controls, transgenic plants grown under high N levels exhibited increased biomass (171.6%) and accumulated higher levels of proteins, chlorophylls and total sugars such as glucose, fructose and sucrose. These plants also exhibited greater nitrogen-use efficiency particularly in young leaves, suggesting that they are able to translocate most of the resources to the above-ground part of the plant to produce biomass. The transgenic poplar transcriptome was greatly affected in response to N availability with 1237 genes differentially regulated in high N, while only 632 genes were differentially expressed in untransformed plants. Many of these genes are essential in the adaptation and response against N excess and include those involved in photosynthesis, cell wall formation and phenylpropanoid biosynthesis. Cellulose production in the transgenic plants was fivefold higher than in control plants, indicating that transgenic poplars represent a potential feedstock for applications in bioenergy. In conclusion, our results show that GS transgenic poplars can be used not only for improving growth and biomass production but also as an important resource for potential phytoremediation of nitrate pollution.

  19. Mammalian cytochrome CYP2E1 triggered differential gene regulation in response to trichloroethylene (TCE) in a transgenic poplar.

    Science.gov (United States)

    Kang, Jun Won; Wilkerson, Hui-Wen; Farin, Federico M; Bammler, Theo K; Beyer, Richard P; Strand, Stuart E; Doty, Sharon L

    2010-08-01

    Trichloroethylene (TCE) is an important environmental contaminant of soil, groundwater, and air. Studies of the metabolism of TCE by poplar trees suggest that cytochrome P450 enzymes are involved. Using poplar genome microarrays, we report a number of putative genes that are differentially expressed in response to TCE. In a previous study, transgenic hybrid poplar plants expressing mammalian cytochrome P450 2E1 (CYP2E1) had increased metabolism of TCE. In the vector control plants for this construct, 24 h following TCE exposure, 517 genes were upregulated and 650 genes were downregulated over 2-fold when compared with the non-exposed vector control plants. However, in the transgenic CYP2E1 plant, line 78, 1,601 genes were upregulated and 1,705 genes were downregulated over 2-fold when compared with the non-exposed transgenic CYP2E1 plant. It appeared that the CYP2E1 transgenic hybrid poplar plants overexpressing mammalian CYP2E1 showed a larger number of differentially expressed transcripts, suggesting a metabolic pathway for TCE to metabolites had been initiated by activity of CYP2E1 on TCE. These results suggest that either the over-expression of the CYP2E1 gene or the abundance of TCE metabolites from CYP450 2E1 activity triggered a strong genetic response to TCE. Particularly, cytochrome p450s, glutathione S-transferases, glucosyltransferases, and ABC transporters in the CYP2E1 transgenic hybrid poplar plants were highly expressed compared with in vector controls.

  20. The Populus superoxide dismutase gene family and its responses to drought stress in transgenic poplar overexpressing a pine cytosolic glutamine synthetase (GS1a.

    Directory of Open Access Journals (Sweden)

    Juan Jesús Molina-Rueda

    Full Text Available BACKGROUND: Glutamine synthetase (GS plays a central role in plant nitrogen assimilation, a process intimately linked to soil water availability. We previously showed that hybrid poplar (Populus tremula X alba, INRA 717-1B4 expressing ectopically a pine cytosolic glutamine synthetase gene (GS1a display enhanced tolerance to drought. Preliminary transcriptome profiling revealed that during drought, members of the superoxide dismutase (SOD family were reciprocally regulated in GS poplar when compared with the wild-type control, in all tissues examined. SOD was the only gene family found to exhibit such patterns. RESULTS: In silico analysis of the Populus genome identified 12 SOD genes and two genes encoding copper chaperones for SOD (CCSs. The poplar SODs form three phylogenetic clusters in accordance with their distinct metal co-factor requirements and gene structure. Nearly all poplar SODs and CCSs are present in duplicate derived from whole genome duplication, in sharp contrast to their predominantly single-copy Arabidopsis orthologs. Drought stress triggered plant-wide down-regulation of the plastidic copper SODs (CSDs, with concomitant up-regulation of plastidic iron SODs (FSDs in GS poplar relative to the wild type; this was confirmed at the activity level. We also found evidence for coordinated down-regulation of other copper proteins, including plastidic CCSs and polyphenol oxidases, in GS poplar under drought conditions. CONCLUSIONS: Both gene duplication and expression divergence have contributed to the expansion and transcriptional diversity of the Populus SOD/CCS families. Coordinated down-regulation of major copper proteins in drought-tolerant GS poplars supports the copper cofactor economy model where copper supply is preferentially allocated for plastocyanins to sustain photosynthesis during drought. Our results also extend previous findings on the compensatory regulation between chloroplastic CSDs and FSDs, and suggest that this

  1. Comparative Transcriptomic Study of Muscle Provides New Insights into the Growth Superiority of a Novel Grouper Hybrid.

    Science.gov (United States)

    Sun, Ying; Huang, Yu; Hu, Guojun; Zhang, Xinhui; Ruan, Zhiqiang; Zhao, Xiaomeng; Guo, Chuanyu; Tang, Zhujing; Li, Xiaofeng; You, Xinxin; Lin, Haoran; Zhang, Yong; Shi, Qiong

    2016-01-01

    Grouper (Epinephelus spp.) is a group of fish species with great economic importance in Asian countries. A novel hybrid grouper, generated by us and called the Hulong grouper (Hyb), has better growth performance than its parents, E. fuscoguttatus (Efu, ♀) and E. lanceolatus (Ela, ♂). We previously reported that the GH/IGF (growth hormone/insulin-like growth factor) system in the brain and liver contributed to the superior growth of the Hyb. In this study, using transcriptome sequencing (RNA-seq) and quantitative real-time PCR (qRT-PCR), we analyzed RNA expression levels of comprehensive genes in the muscle of the hybrid and its parents. Our data showed that genes involved in glycolysis and calcium signaling in addition to troponins are up-regulated in the Hyb. The results suggested that the activity of the upstream GH/IGF system in the brain and liver, along with the up-regulated glycolytic genes as well as ryanodine receptors (RyRs) and troponins related to the calcium signaling pathway in muscle, led to enhanced growth in the hybrid grouper. Muscle contraction inducing growth could be the major contributor to the growth superiority in our novel hybrid grouper, which may be a common mechanism for hybrid superiority in fishes.

  2. Effect of growth regulators on growth of hybrids of east hellebore (Helleborus orientalis Lam.

    Directory of Open Access Journals (Sweden)

    Monika Henschke

    2014-12-01

    Full Text Available The aim of the study was to determine the effect of growth regulators in foliar or soil applications on the growth of Helleborus orientalis ‘Red Hybrids’. Used benzyladenine, gibberellic acid and flurprimidol varying concentrations depending on the method of application. Plant growth was assessed on the basis of plant height, number of resume buds and the number of leaves. Type of growth regulator and method of application had a significant impact on the features. It has been found that the use of BA or BA+GA3, regardless of the application method, will increase the number of resume buds and leaves and decrease the plant height. Flurprimidol in­hibits plant growth, and does not increase the number of resume buds and leaves. In the cultivation of Helleborus orientalis it is recommended to water the plants twice with a mixture of solutions of BA 500 mg·dm-3 + GA3 150 mg·dm-3 at a dose of 50 cm3 per 1 dm3 of medium.

  3. Stability Analysis of a Hybrid Cellular Automaton Model of Cell Colony Growth

    CERN Document Server

    Gerlee, P

    2007-01-01

    Cell colonies of bacteria, tumour cells and fungi, under nutrient limited growth conditions, exhibit complex branched growth patterns. In order to investigate this phenomenon we present a simple hybrid cellular automaton model of cell colony growth. In the model the growth of the colony is limited by a nutrient that is consumed by the cells and which inhibits cell division if it falls below a certain threshold. Using this model we have investigated how the nutrient consumption rate of the cells affects the growth dynamics of the colony. We found that for low consumption rates the colony takes on a Eden-like morphology, while for higher consumption rates the morphology of the colony is branched with a fractal geometry. These findings are in agreement with previous results, but the simplicity of the model presented here allows for a linear stability analysis of the system. By observing that the local growth of the colony is proportional to the flux of the nutrient we derive an approximate dispersion relation fo...

  4. Diversity of arthropod community in transgenic poplar-cotton ecosystems.

    Science.gov (United States)

    Zhang, D J; Lu, Z Y; Liu, J X; Li, C L; Yang, M S

    2015-12-02

    Poplar-cotton agro-ecosystems are the main agricultural planting modes of plain cotton fields in China. Here, we performed a systematic survey of the diversity and population of arthropod communities in four different combination of poplar-cotton eco-systems, including I) non-transgenic poplar and non-transgenic cotton fields; II) non-transgenic poplar and transgenic cotton fields [Bacillus thuringiensis (Bt) cotton]; III) Bt transgenic poplar (high insect resistant strain Pb29) and non-transgenic cotton; and IV) transgenic poplar and transgenic cotton fields, over a period of 3 years. Based on the statistical methods used to investigate community ecology, the effects of transgenic ecosystems on the whole structure of the arthropod community, on the structure of arthropods in the nutritive layer, and on the similarity of arthropod communities were evaluated. The main results were as follows: the transgenic poplar-cotton ecosystem has a stronger inhibitory effect on insect pests and has no impact on the structure of the arthropod community, and therefore, maintains the diversity of the arthropod community. The character index of the community indicated that the structure of the arthropod community of the transgenic poplar-cotton ecosystem was better than that of the poplar-cotton ecosystem, and that system IV had the best structure. As for the abundance of nutritional classes, the transgenic poplar-cotton ecosystem was also better than that of the non-transgenic poplar-cotton ecosystem. The cluster analysis and similarity of arthropod communities between the four different transgenic poplar-cotton ecosystems illustrated that the structure of the arthropod community excelled in the small sample of the transgenic poplar-cotton ecosystems.

  5. Biomass productivity and water use relation in short rotation poplar coppice (Populus nigra x P. maximowiczii in the conditions of Czech Moravian Highlands

    Directory of Open Access Journals (Sweden)

    Milan Fischer

    2011-01-01

    Full Text Available The plantations of short rotation coppice (SRC usually based on poplar or willow species are promising source of biomass for energy use. To contribute to decision-making process where to establish the plantations we evaluated the water consumption and its relation to biomass yields of poplar hybrid clone J-105 (Populus nigra x P. maximowiczii in representative conditions for Czech-Moravian Highlands. Water availability is usually considered as one of the main constraints of profitable SRC culture and therefore we focused on analyzing of the linkage between the aboveground biomass increments and the total stand actual evapotranspiration (ETa and on water use efficiency of production (WUEP. During the seasons 2008 and 2009 the total stand ETa measured by Bowen ratio energy balance system constructed above poplar canopy and the stem diameter increments of randomly chosen sample trees were examined. The stem diameters were subsequently converted to total aboveground biomass (AB by allometric equation obtained by destructive analysis at the beginning of 2010. The biomass volume and its increment of particular trees were subsequently converted to the whole canopy growth and correlated with the ETa values. Our results revealed that there was a statistically significant relation between water lost and biomass growth with coefficients of determination r2 0.96 and 0.51 in 2008 and 2009 respectively. By using multiple linear regression analysis additionally accounting for effect of precipitation events and thermal time (sums of effective temperatures above +5 °C the AB growth was explained from 98 and 87% in 2008 and 2009, respectively. Therefore for further analysis the multiple linear regression model was applied. The dynamic of seasonal WUEP (expressed as gram of AB dry matter per thousand grams of water reached up to 6.2 and 6.8 g kg−1 with means 3.13 and 3.54 g kg−1 in both executed years respectively. These values are situated in higher

  6. ALTERATIONS TO PLBS AND PLANTLETS OF HYBRID CYMBIDIUM (ORCHIDACEAE IN RESPONSE TO PLANT GROWTH REGULATORS

    Directory of Open Access Journals (Sweden)

    Jaime A. TEIXEIRA DA SILVA

    2015-12-01

    Full Text Available A previous study examined, in detail, the morphological response of hybrid Cymbidium Twilight Moon ‘Day Light’ protocorm-like bodies (PLBs to 26 plant growth regulators (PGRs. In this study, flow cytometric analyses of the PLBs derived from several of these PGR treatments revealed changes in the ploidy of PLBs while the ploidy of plant leaves remained constant. The SPAD value of leaves of plants derived from PGR treatments changed significantly. The choice of PGR must be accompanied by careful scrutiny of the possible resulting changes to morphology and physiological parameters.

  7. Effects of growth hormone transgenesis on metabolic rate, exercise performance and hypoxia tolerance in tilapia hybrids

    DEFF Research Database (Denmark)

    McKenzie, DJ; Martinez, R; Morales, A

    2003-01-01

    Swimming respirometry was employed to compare inactive metabolic rate (Rr), maximum metabolic rate (Rmax), resultant aerobic scope and maximum sustainable (critical) swimming speed (Ucrit), in growth hormone transgenic (GHT) and wild-type (W) tilapia Oreochromis sp. hybrids. Although the Rr of GHT...... tilapia also exhibited the same capacity to regulate oxygen uptake during progressive hypoxia, despite the fact that the GHT fish were defending a higher demand for O2. The results indicate that ectopic expression of GH raises metabolic rate in tilapia, but the fish compensate for this metabolic load...

  8. Recognition and rating of effecting indexes on consumption of different sites poplar wood production in Iran for paper making industries

    Directory of Open Access Journals (Sweden)

    ebrahim lashkarbolouki

    2016-12-01

    Full Text Available Considering the growth in population, the need for wood consumption also increases. The rapid progress of science and technology doubles the wood consumption. Supplying this need at a glance was focused on the forests. Forests for many reasons have faced decrease in production and this extreme need for wood, by planting fast growing trees (poplar, eucalypt, Paulownia … makes it possible. One of industries plenty of the wood is paper industry that needs to huge primary wood material. This industry can continue their production activities by using the wood of poplar. This research was found out with the aim of assessing the practical characteristics of poplar wood by nondestructive test method in paper production industry. Poplar sites were selected in areas of country that poplar trees were planted widely. For locating the production of different site in paper industry found out Analytic Hierarchy Process (AHP in Expert choice 11 software. For field studies of this research, the questionnaires were prepared and sent for expert and university professors with special expertise in this industry. The results showed that: Production of Pulp and paper industry: in this industry among of five main indexes influencing in pulp and paper production, fiber morphology trait recognized as first priority with weighting value (0.435. Production allocations with their weighting value are determined: Sari (0.240, Fouman (0.236, Lashtnasha (0.182, Abhar (0.174 and Zanjan (0.168, respectively.

  9. Early growth and development of reciprocal hybrids of the starry flounder Platichthys stellatus and stone flounder Kareius bicoloratus.

    Science.gov (United States)

    Yamashita, Y T; Aritaki, M; Kurita, Y; Tanaka, M

    2014-05-01

    Larval growth and development of hybrid flounder were observed and compared with those of their parent species. The reciprocal hybrids of female starry flounder Platichthys stellatus and male stone flounder Kareius bicoloratus (hybrid Sb) and of female K. bicoloratus and male P. stellatus (hybrid Bs) both survived and grew to juveniles. Development was divided into nine stages (A-I). Many of the hybrids' traits were identical and intermediate to those of their parents. The position of the eye, however, was primarily sinistral in both hybrids (80% in Sb and 76% in Bs), a trait possessed by P. stellatus (80%) in the western Pacific Ocean. The daily growth rates of the larvae were similar. In the parent species, development was more rapid in P. stellatus than in K. bicoloratus whereas rate of development was intermediate in both Sb and Bs hybrids. The size at settlement [standard length (LS ) at stage H (mean ± s.d.)] was 9·82 ± 1·47 mm for the hybrid Sb and 9·99 ± 0·90 mm for the hybrid Bs, while the minimum age at metamorphosis (initial age at stage H) was 29 days after hatching (DAH) in both hybrids. In comparison, LS at settlement in parent species was 6·43 ± 0·25 mm for P. stellatus and 12·87 ± 1·29 mm for K. bicoloratus. Minimum age at metamorphosis for the parents was 23 DAH at stage G in P. stellatus and 34 DAH at stage H in K. bicoloratus. Thus, the timing of settlement of hybrids was different from that of their parent species. These traits may occur with high frequency in a natural habitat. © 2014 The Fisheries Society of the British Isles.

  10. Growth Performance, Length-Weight Relationship and Condition Factor of Backcross and Reciprocal Hybrid Catfish Reared in Net Cages

    Directory of Open Access Journals (Sweden)

    Paiboon Panase

    2015-01-01

    Full Text Available This study was designed to investigate the growth performance, Length-Weight Relationship (LWR and condition factor (k-value of reciprocal backcross hybrid catfish (RCBC, Pangasianodon gigas (femalexF1 hybrid (male catfish and backcross hybrid catfish (BC, P. gigas (malexF1 hybrid (female catfish. Moreover, this study also compared the above mentioned species of catfish were compared with P. gigas and F1 hybrid P. gigas (malexP. hypophthalmus (female catfish. The fish were reared in net cages for 5 months (October, 2013-March, 2014. The results showed that, Weight Gain (WG and average daily weight gain (ADG were the highest among the P. gigas (34.45 and 0.20, respectively. The Length Gain (LG, average daily length gain (ADL and Specific Growth Rate (SGR were highest among the RCBC (10.66, 0.062 and 2.34, respectively. While the survival rate (55% was highest among the BC. The Feed Conversion Rate (FCR showed high numbers in all fish except the hybrids. On the other hand, the hybrid species showed lower results in all growth indices except for the survival rate but which had as high a tendency as the RCBC. The LWR revealed “b” values for the P. gigas, RCBC, BC and F1 hybrid that were 2.94, 3.12, 2.67 and 2.03 indicating that P. gigas and RCBC displayed isometric growth while others showed allometric growth. The k-values for each month showed significant differences (p0.05. The results from this study revealed that the RCBC is suitable for the aquaculture industry and moreover, the information collected in this study on LWR and the condition factor of each fish will be useful for fishery management.

  11. Can we use short rotation coppice poplar for sugar based biorefinery feedstock? Bioconversion of 2-year-old poplar grown as short rotation coppice.

    Science.gov (United States)

    Dou, Chang; Marcondes, Wilian F; Djaja, Jessica E; Bura, Renata; Gustafson, Rick

    2017-01-01

    Feedstock cost is a substantial barrier to the commercialization of lignocellulosic biorefineries. Poplar grown using a short rotation coppice (SRC) system has the potential to provide a low-cost feedstock and economically viable sugar yields for fuels and chemicals production. In the coppice management regime, poplars are harvested after 2 years' growth to develop the root system and establish the trees. The biomass from these 2-year-old trees is very heterogeneous, and includes components of leaf, bark, branch, and wood chip. This material is quite different than the samples that have been used in most poplar bioconversion research, which come from mature trees of short rotation forestry (SRF) plantations. If the coppice management regime is to be used, it is important that feedstock growers maximize their revenue from this initial harvest, but the heterogeneous nature of the biomass may be challenging for bioconversion. This work evaluates bioconversion of 2-year-old poplar coppice and compares its performance to whitewood chips from 12-year-old poplar. The 2-year-old whole tree coppice (WTC) is comprised of 37% leaf, 9% bark, 12% branch, and 42% wood chip. As expected, the chemical compositions of each component were markedly different. The leaf has a low sugar content but is high in phenolics, ash, and extractives. By removing the leaves, the sugar content of the biomass increased significantly, while the phenolic, ash, and extractives contents decreased. Leaf removal improved monomeric sugar yield by 147 kg/tonne of biomass following steam pretreatment and enzymatic hydrolysis. Bioconversion of the no-leaf coppice (NLC) achieved a 67% overall sugar recovery, showing no significant difference to mature whitewood from forestry plantation (WWF, 71%). The overall sugar yield of NLC was 135 kg/tonne less than that of WWF, due to the low inherent sugar content in original biomass. An economic analysis shows the minimum ethanol selling price required to cover the

  12. In vitro growth of bioactive nanostructured apatites via agar-gelatin hybrid hydrogel.

    Science.gov (United States)

    Deng, Yi; Zhao, Xianghui; Zhou, Yongsheng; Zhu, Peizhi; Zhang, Li; Wei, Shicheng

    2013-12-01

    Biomimetic synthesis of bone-like carbonated apatite with good biocompatibility is a promising strategy for the development of novel biomaterials for bone engineering applications. Most research efforts have been focused on only protein-based or only polysaccharide-based template for synthesis of apatite minerals. To understand the cooperative roles of gelatin and polysaccharide playing in the biomineralization, agar hydrogel, gelatin and agar-gelatin hybrid hydrogel were respectively introduced as mineralization matrix for the in vitro growth of apatite in the study. It was shown that bundle-like carbonated apatite was successfully prepared in agar-gelatin hybrid hydrogel for the first time, through the interaction between apatite and matrix macromolecule under physiological temperature. Moreover, the in vitro biocompatibility of the prepared nanostructured apatite crystals was investigated using CCK-8 assay and alkaline phosphatase activity of osteoblast-like MC3T3-E1. Compared with HA synthesized by traditional method, the obtained apatite in agar-gelatin hybrid hydrogel could provide significantly higher cell viability and alkaline phosphatase activity. Through the study, we could better understand the role of gelatin and polysaccharide in bone formation process, and the product is a promising candidate to be used in bone tissue engineering.

  13. Drought Induced Changes in Growth, Osmolyte Accumulation and Antioxidant Metabolism of Three Maize Hybrids

    Science.gov (United States)

    Anjum, Shakeel A.; Ashraf, Umair; Tanveer, Mohsin; Khan, Imran; Hussain, Saddam; Shahzad, Babar; Zohaib, Ali; Abbas, Farhat; Saleem, Muhammad F.; Ali, Iftikhar; Wang, Long C.

    2017-01-01

    Consequences of drought stress in crop production systems are perhaps more deleterious than other abiotic stresses under changing climatic scenarios. Regulations of physio-biochemical responses of plants under drought stress can be used as markers for drought stress tolerance in selection and breeding. The present study was conducted to appraise the performance of three different maize hybrids (Dong Dan 80, Wan Dan 13, and Run Nong 35) under well-watered, low, moderate and SD conditions maintained at 100, 80, 60, and 40% of field capacity, respectively. Compared with well-watered conditions, drought stress caused oxidative stress by excessive production of reactive oxygen species (ROS) which led to reduced growth and yield formation in all maize hybrids; nevertheless, negative effects of drought stress were more prominent in Run Nong 35. Drought-induced osmolyte accumulation and strong enzymatic and non-enzymatic defense systems prevented the severe damage in Dong Dan 80. Overall performance of all maize hybrids under drought stress was recorded as: Dong Dan 80 > Wan Dan 13 > Run Nong 35 with 6.39, 7.35, and 16.55% yield reductions. Consequently, these biochemical traits and differential physiological responses might be helpful to develop drought tolerance genotypes that can withstand water-deficit conditions with minimum yield losses. PMID:28220130

  14. Mapping growth windows in quaternary perovskite oxide systems by hybrid molecular beam epitaxy

    Science.gov (United States)

    Brahlek, Matthew; Zhang, Lei; Zhang, Hai-Tian; Lapano, Jason; Dedon, Liv R.; Martin, Lane W.; Engel-Herbert, Roman

    2016-09-01

    Requisite to growing stoichiometric perovskite thin films of the solid-solution A'1-xAxBO3 by hybrid molecular beam epitaxy is understanding how the growth conditions interpolate between the end members A'BO3 and ABO3, which can be grown in a self-regulated fashion, but under different conditions. Using the example of La1-xSrxVO3, the two-dimensional growth parameter space that is spanned by the flux of the metal-organic precursor vanadium oxytriisopropoxide and composition, x, was mapped out. The evolution of the adsorption-controlled growth window was obtained using a combination of X-ray diffraction, atomic force microscopy, reflection high-energy electron-diffraction (RHEED), and Rutherford backscattering spectroscopy. It is found that the stoichiometric growth conditions can be mapped out quickly with a single calibration sample using RHEED. Once stoichiometric conditions have been identified, the out-of-plane lattice parameter can be utilized to precisely determine the composition x. This strategy enables the identification of growth conditions that allow the deposition of stoichiometric perovskite oxide films with random A-site cation mixing, which is relevant to a large number of perovskite materials with interesting properties, e.g., high-temperature superconductivity and colossal magnetoresistance, that emerge in solid solution A'1-xAxBO3.

  15. Influences of altitude on growth curves in Tibetan chicken and its hybrid

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Tibetan chicken is a precious resource in Qinghai-Tibet Plateau,China.In order to study its growth rhythm and heterosis of its hybrid,three groups comprising Tibetan chicken (T),Dwarf Recessive White (D) and Tibetan×Dwarf Recessive White (TD) were reared under the same management conditions at low and high altitudes.Body weight and shank length were measured,and growth curves were fitted using Richards model.The results showed that the model fitted well with the chickens' growth courses in weight and shank with R2 at more than 0.99.The high-altitude might retard the growth of chickens,with decreases in inflection point values,final values and maximal growth rates,and prolongation of inflection point time.The final weight,inflection point weight,and maximal growth rates of Tibetan chicken were 1008.3 g,477.9 g and 11.69 g respectively at lowaltitude,and 525.3 g,229.5 g,and 5.12 g at high-altitude.This showed a decline of 47.9%,52.0%,and 56.8% at the high-altitude;the degree of influence of altitude was less than that of Dwarf Recessive White.The TD had high heterosis in weight gain,and at high-altitude the heterosis of final weight,inflection point weight,and maximal growth rates were 59.5%,56.8% and 52.3% respectively.Therefore,the Tibetan×Dwarf Recessive White cross was good for improving the Tibetan chicken.

  16. ADVANCING PROTOCOLS FOR POPLARS in vitro PROPAGATION, REGENERATION AND SELECTION OF TRANSFORMANTS

    Directory of Open Access Journals (Sweden)

    Nataliia Kutsokon

    2013-02-01

    Full Text Available Poplars (genus Populus have emerged as a model organism for forest biotechnology, and genetic modification is more advanced for this genus than for any other tree. So far several protocols for microclonal propagation and regeneration for Populus species have been developed. However it is well known that these protocols differ for various species and need to be adapted even for different clones of the same species. This work was focused on developing of protocols for propagation, regeneration and putative transformant´s selection of aspen Populus tremula L. and other two fast-growing Populus species (P. nigra L., P. x canadensis Moench. The regeneration ability for black poplar explants was demonstrated to be three times higher compared to those for aspen and hybrid poplar. It was found that concentration 1 mg/L of phosphinothricin and 25 mg/L of kanamycin is toxic for non- transgenic plant tissues of P. x canadensis and can be applied in transformation experiments when genes of resistance to the corresponding selective agents into the plant genome are introduced.

  17. A hybrid cellular automaton model of solid tumor growth and bioreductive drug transport.

    Science.gov (United States)

    Kazmi, Nabila; Hossain, M A; Phillips, Roger M

    2012-01-01

    Bioreductive drugs are a class of hypoxia selective drugs that are designed to eradicate the hypoxic fraction of solid tumors. Their activity depends upon a number of biological and pharmacological factors and we used a mathematical modeling approach to explore the dynamics of tumor growth, infusion, and penetration of the bioreductive drug Tirapazamine (TPZ). An in-silico model is implemented to calculate the tumor mass considering oxygen and glucose as key microenvironmental parameters. The next stage of the model integrated extra cellular matrix (ECM), cell-cell adhesion, and cell movement parameters as growth constraints. The tumor microenvironments strongly influenced tumor morphology and growth rates. Once the growth model was established, a hybrid model was developed to study drug dynamics inside the hypoxic regions of tumors. The model used 10, 50 and 100 \\mu {\\rm M} as TPZ initial concentrations and determined TPZ pharmacokinetic (PK) (transport) and pharmacodynamics (cytotoxicity) properties inside hypoxic regions of solid tumor. The model results showed that diminished drug transport is a reason for TPZ failure and recommend the optimization of the drug transport properties in the emerging TPZ generations. The modeling approach used in this study is novel and can be a step to explore the behavioral dynamics of TPZ.

  18. Hybrid molecular beam epitaxy for the growth of stoichiometric BaSnO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Prakash, Abhinav, E-mail: praka019@umn.edu; Dewey, John; Yun, Hwanhui; Jeong, Jong Seok; Mkhoyan, K. Andre; Jalan, Bharat, E-mail: bjalan@umn.edu [Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2015-11-15

    Owing to its high room-temperature electron mobility and wide bandgap, BaSnO{sub 3} has recently become of significant interest for potential room-temperature oxide electronics. A hybrid molecular beam epitaxy (MBE) approach for the growth of high-quality BaSnO{sub 3} films is developed in this work. This approach employs hexamethylditin as a chemical precursor for tin, an effusion cell for barium, and a radio frequency plasma source for oxygen. BaSnO{sub 3} films were thus grown on SrTiO{sub 3} (001) and LaAlO{sub 3} (001) substrates. Growth conditions for stoichiometric BaSnO{sub 3} were identified. Reflection high-energy electron diffraction (RHEED) intensity oscillations, characteristic of a layer-by-layer growth mode were observed. A critical thickness of ∼1 nm for strain relaxation was determined for films grown on SrTiO{sub 3} using in situ RHEED. Scanning transmission electron microscopy combined with electron energy-loss spectroscopy and energy dispersive x-ray spectroscopy confirmed the cube-on-cube epitaxy and composition. The importance of precursor chemistry is discussed in the context of the MBE growth of BaSnO{sub 3}.

  19. DESIGNING A FORECAST MODEL FOR ECONOMIC GROWTH OF JAPAN USING COMPETITIVE (HYBRID ANN VS MULTIPLE REGRESSION MODELS

    Directory of Open Access Journals (Sweden)

    Ahmet DEMIR

    2015-07-01

    Full Text Available Artificial neural network models have been already used on many different fields successfully. However, many researches show that ANN models provide better optimum results than other competitive models in most of the researches. But does it provide optimum solutions in case ANN is proposed as hybrid model? The answer of this question is given in this research by using these models on modelling a forecast for GDP growth of Japan. Multiple regression models utilized as competitive models versus hybrid ANN (ANN + multiple regression models. Results have shown that hybrid model gives better responds than multiple regression models. However, variables, which were significantly affecting GDP growth, were determined and some of the variables, which were assumed to be affecting GDP growth of Japan, were eliminated statistically.

  20. 高效解磷细菌与菌根真菌菌剂交互作用对杨树的促生效应%Interaction between high effective phosphate-solubilizing bacteria and mycorrhizal fungi and its effects on poplar growth

    Institute of Scientific and Technical Information of China (English)

    姚如斌; 吴小芹

    2012-01-01

    Poplar were fertilized with different types of capsule agent Bacillus cereus ( JYZ-SD1) , Pseudomonas fluorescent (JW-JS1) , Xerocomus cheysenteron(Xc) and their mixture (JYZ-SD1 +Xc, JW-JS1 +Xc, JYZ-SD1 + JW-JS1 + Xc) in liquid and solid forms, and the growth status and the photosynthesis characters were determined. The results showed that the mixed liquid agent comprised of JYZ-SD1 , JW-JS1 and Xc greatly promoted the poplar growth and pho-tosynthetic efficiency while the corresponding solid capsule agent displayed a relatively equal promotion effects. No significant differences between capsule agent and other forms. The promotion effects of B. cereus ( JYZ-SD1) was better than that of P. fluorescens ( JW-JS1) .%近年来,高效解磷细菌与菌根真菌互作对植物的促生效应受到广泛的关注.笔者分别制备3种单菌胶丸菌剂[蜡状芽孢杆菌(Bacillus cereus,JYZ-SD1)、荧光假单孢菌(pseudomonas fluorescens,JW-JS1)、红绒盖牛肝菌(Xerocomus cheysenteron,Xc)]和3种复合胶丸菌剂[JYZ-SD1+Xc、JW-JS1+Xc、JYZ-SD1 +JW-JS1 +Xc].将单菌胶丸菌剂和3菌复合胶丸菌剂对杨树施用后,测定其对苗木的生长及光合作用的影响,并与液体菌液和固体菌剂相比较.结果表明,JYZ-SD1、JW-JS1和Xc的3菌复合液体菌液对杨苗的促生及光合效应促进最大,3菌复合胶丸菌剂次之,但与其复合液体菌液无显著差异.JYZ-SD1的菌剂促生效果好于JW-JS1菌剂的处理.

  1. Unraveling the growth determinism of Fagus sylvatica: a hybrid data-model approach

    Science.gov (United States)

    Guillemot, Joannès; Martin-StPaul, Nicolas; Delpierre, Nicolas; François, Christophe; Soudani, Kamel; Restoux, Gwendal; Dufrêne, Eric

    2013-04-01

    The physiological processes underlying the limitation of forest growth are still under debate. Growth has long been considered as a carbone (C) limited process (Sala et al., 2012). As a matter of facts, a recent global meta-analysis has shown good agreements between assimilated C and forest productivity (Litton et al., 2007). Consequently, a majority of the process-based productivity models considers growth as a fraction of the net primary production (NPP) (Lacointe et al., 2000; Sitch et al., 2003. However, investigations at the stand scale report conflicting results (Rocha et al., 2006, Mund et al., 2010) and are not systematically consistent with a strict C limitation of growth, thus challenging the C-centric paradigm. The mechanisms that potentially degrade the link between NPP and growth include: i) the direct effect of environmental factors on growth (Zweifel et al., 2006, Körner et al., 2003), ii) the temporal variability of the growth allocation coefficient, due either to ontogeny (Genet et al., 2009), or to the initial physiological state of the tree i.e. to the reaction to past conditions. Indeed, many dendrochronological and ecological studies have shown a correlation between growth and climatic factors of the previous years (e.g. Lebourgeois et al., 2005; Richardson et al., 2012). In this work, we used a hybrid data model approach in order to assess the determinant of Fagus sylvatica stem growth along a spatial gradient across France. Despite they could brought essential insight on tree functioning, intra-specific studies across contrasted sites are still lacking in the current debate. Standardized annual growth data series at the stand scale were calculated using circumference inventories and dendrochronological series on 17 plots of the RENECOFOR network. We used the process-based model CASTANEA, thoroughly validated in long term flux simulation across Europe (e.g. Delpierre et al. 2009), to simulate the annual NPP of the corresponding periods. We

  2. Evaluation of Lower East Fork Poplar Creek Mercury Sources

    Energy Technology Data Exchange (ETDEWEB)

    Watson, David B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Brooks, Scott C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mathews, Teresa J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevelhimer, Mark S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DeRolph, Chris [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Brandt, Craig C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Peterson, Mark J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ketelle, Richard [East Tennessee Technology Park (ETTP), Oak Ridge, TN (United States)

    2016-06-01

    This report summarizes a 3-year research project undertaken to better understand the nature and magnitude of mercury (Hg) fluxes in East Fork Poplar Creek (EFPC). This project addresses the requirements of Action Plan 1 in the 2011 Oak Ridge Reservation-wide Comprehensive Environmental Response, Compensation, and Liability Act Five Year Review (FYR). The Action Plan is designed to address a twofold 2011 FYR issue: (1) new information suggests mobilization of mercury from the upper and lower EFPC streambeds and stream banks is the primary source of mercury export during high-flow conditions, and (2) the current Record of Decision did not address the entire hydrologic system and creek bank or creek bed sediments. To obtain a more robust watershed-scale understanding of mercury sources and processes in lower EFPC (LEFPC), new field and laboratory studies were coupled with existing data from multiple US Department of Energy programs to develop a dynamic watershed and bioaccumulation model. LEFPC field studies for the project focused primarily on quantification of streambank erosion and an evaluation of mercury dynamics in shallow groundwater adjacent to LEFPC and potential connection to the surface water. The approach to the stream bank study was innovative in using imagery from kayak floats’ surveys from the headwaters to the mouth of EFPC to estimate erosion, coupled with detailed bank soil mercury analyses. The goal of new field assessments and modeling was to generate a more holistic and quantitative understanding of the watershed and the sources, flux, concentration, transformation, and bioaccumulation of inorganic mercury (IHg) and methylmercury (MeHg). Model development used a hybrid approach that dynamically linked a spreadsheet-based physical and chemical watershed model to a systems dynamics, mercury bioaccumulation model for key fish species. The watershed model tracks total Hg and MeHg fluxes and concentrations by examining upstream inputs, floodplain

  3. Studies on the Growth Habits and Characteristics of Two Polyploid Indica-Japonica Hybrid Rice with Powerful Heterosis

    Institute of Scientific and Technical Information of China (English)

    SONG Zhao-jian; DU Chao-qun; DAI Bing-cheng; CHEN Dong-ling; CHEN Jian-guo; CAI De-tian

    2007-01-01

    Based on a series of polyploid indica-japonica hybrid plant lines obtained from a new breeding strategy of using double predominance of wide cross and polyploidization to breed super rice, two polyploid indica-japonica hybrids, PSR073 and PSR120 were studied in their growth periods to show the powerful heterosis in a larger scale and to study the characteristics of polyploid indica-japonica hybrids more elaborately. The leaf age, tiller growth, flowering habits, and agronomic traits of them were observed to analyze their growth habits and characteristics. The results showed that the.agronomic traits of PSR073 and PSR 120, such as the plant height, panicle length, grain length, grain width, and 1000-grain weight, all acquired obvious predominance of polyploidy, and that the seed setting rate was more than 83%. No significant difference was observed between the two tetraploids and common diploids in the leaf age, tiller growth, and flowering habits. It was concluded that the characteristics of the two powerful heterosis polyploid hybrids were different from those of the polyploid rice reported earlier. Wide cross and polyploidization had no negative effects on their growth habits and characteristics; on the contrary these had powerful heterosis. This had provided theoretic and practical evidences for their application to agricultural production.

  4. Cometabolic degradation of trichloroethylene by Burkholderia cepacia G4 with poplar leaf homogenate.

    Science.gov (United States)

    Kang, Jun Won; Doty, Sharon Lafferty

    2014-07-01

    Trichloroethylene (TCE), a chlorinated organic solvent, is one of the most common and widespread groundwater contaminants worldwide. Among the group of TCE-degrading aerobic bacteria, Burkholderia cepacia G4 is the best-known representative. This strain requires the addition of specific substrates, including toluene, phenol, and benzene, to induce the enzymes to degrade TCE. However, the substrates are toxic and introducing them into the soil can result in secondary contamination. In this study, poplar leaf homogenate containing natural phenolic compounds was tested for the ability to induce the growth of and TCE degradation by B. cepacia G4. The results showed that the G4 strain could grow and degrade TCE well with the addition of phytochemicals. The poplar leaf homogenate also functioned as an inducer of the toluene-ortho-monooxygenase (TOM) gene in B. cepacia G4.

  5. Growth of SrVO{sub 3} thin films by hybrid molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Eaton, Craig; Brahlek, Matthew; Engel-Herbert, Roman, E-mail: rue2@psu.edu [Department of Material Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Moyer, Jarrett A. [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Alipour, Hamideh M.; Grimley, Everett D.; LeBeau, James M. [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2015-11-15

    The authors report the growth of stoichiometric SrVO{sub 3} thin films on (LaAlO{sub 3}){sub 0.3}(Sr{sub 2}AlTaO{sub 6}){sub 0.7} (001) substrates using hybrid molecular beam epitaxy. This growth approach employs a conventional effusion cell to supply elemental A-site Sr and the metalorganic precursor vanadium oxytriisopropoxide (VTIP) to supply vanadium. Oxygen is supplied in its molecular form through a gas inlet. An optimal VTIP:Sr flux ratio has been identified using reflection high-energy electron-diffraction, x-ray diffraction, atomic force microscopy, and scanning transmission electron microscopy, demonstrating stoichiometric SrVO{sub 3} films with atomically flat surface morphology. Away from the optimal VTIP:Sr flux, characteristic changes in the crystalline structure and surface morphology of the films were found, enabling identification of the type of nonstoichiometry. For optimal VTIP:Sr flux ratios, high quality SrVO{sub 3} thin films were obtained with smallest deviation of the lattice parameter from the ideal value and with atomically smooth surfaces, indicative of the good cation stoichiometry achieved by this growth technique.

  6. Hybrid liposomes inhibit tumor growth and lung metastasis of murine osteosarcoma cells.

    Science.gov (United States)

    Kitajima, Hideki; Komizu, Yuji; Ichihara, Hideaki; Goto, Koichi; Ueoka, Ryuichi

    2013-06-01

    Antitumor effects of hybrid liposomes (HL) composed of l-α-dimyristoylphosphatidylcholine (DMPC) and polyoxyethylene(23) dodecyl ether (C₁₂(EO)₂₃) on the metastatic growth of murine osteosarcoma (LM8) cells were investigated in vitro and in vivo. Remarkable inhibitory effects of HL-23 on the growth of LM8 cells were obtained through the induction of apoptotic cell death in vitro. It was also indicated that HL-23 should dramatically suppress the invasion of LM8 cells and the formation of filopodia on the cell surface in vitro. Furthermore, significantly high therapeutic effects were observed in the homograft mouse models of LM8 cells with lung metastasis after the treatment with HL-23 in vivo. That is, the histological analysis demonstrated that the primary tumor growth of LM8 cells implanted subcutaneously into the mice was inhibited along with the induction of apoptosis. In addition, it was found that HL-23 significantly decreased the lung metastasis of LM8 cells in the mouse models through the inhibition of primary tumor invasion. These results suggest that HL-23 could be a novel agent for the chemotherapy of osteosarcoma.

  7. How light, temperature, and measurement and growth [CO2] interactively control isoprene emission in hybrid aspen.

    Science.gov (United States)

    Niinemets, Ülo; Sun, Zhihong

    2015-02-01

    Plant isoprene emissions have been modelled assuming independent controls by light, temperature and atmospheric [CO2]. However, the isoprene emission rate is ultimately controlled by the pool size of its immediate substrate, dimethylallyl diphosphate (DMADP), and isoprene synthase activity, implying that the environmental controls might interact. In addition, acclimation to growth [CO2] can shift the share of the control by DMADP pool size and isoprene synthase activity, and thereby alter the environmental sensitivity. Environmental controls of isoprene emission were studied in hybrid aspen (Populus tremula × Populus tremuloides) saplings acclimated either to ambient [CO2] of 380 μmol mol(-1) or elevated [CO2] of 780 μmol mol(-1). The data demonstrated strong interactive effects of environmental drivers and growth [CO2] on isoprene emissions. Light enhancement of isoprene emission was the greatest at intermediate temperatures and was greater in elevated-[CO2]-grown plants, indicating greater enhancement of the DMADP supply. The optimum temperature for isoprene emission was higher at lower light, suggesting activation of alternative DMADP sinks at higher light. In addition, [CO2] inhibition of isoprene emission was lost at a higher temperature with particularly strong effects in elevated-[CO2]-grown plants. Nevertheless, DMADP pool size was still predicted to more strongly control isoprene emission at higher temperatures in elevated-[CO2]-grown plants. We argue that interactive environmental controls and acclimation to growth [CO2] should be incorporated in future isoprene emission models at the level of DMADP pool size.

  8. Growth and yield of corn hybrids in response to association with Azospirillum brasilense and nitrogen fertilization

    Directory of Open Access Journals (Sweden)

    Deniele Marini

    2015-02-01

    Full Text Available There is a growing interest in optimizing the positive effects of the association between Azospirillum bacteria and corn crop in order to reduce the use of nitrogen fertilizers. This study aimed to evaluate the inoculation efficiency of an A. brasilense-based commercial product in association with different rates of nitrogen fertilization in two corn genotypes. The experiment was arranged in a 2 x 2 x 5 factorial randomized block design, with four replications. The treatments consisted of two corn hybrids (30F53 and CD386; with and without inoculation with a commercial product based on A. brasilense and five nitrogen rates (0, 40, 80, 120 and 160 kg ha-1. The variables plant height, basal stem diameter, leaf area, shoot dry matter, leaf nitrogen content, length and diameter of the cob, weight of 100 grains and grain yield were evaluated. Inoculation with A. brasilense provided increases of 11 and 12% in leaf area and shoot dry matter, respectively. There were differences in the response of the corn hybrids for most variables and the increase in nitrogen supply provided increments in the growth and yield of corn.

  9. Organic Gelators as Growth Control Agents for Stable and Reproducible Hybrid Perovskite-Based Solar Cells

    KAUST Repository

    Masi, Sofia

    2017-03-03

    Low-molecular-weight organic gelators are widely used to influence the solidification of polymers, with applications ranging from packaging items, food containers to organic electronic devices, including organic photovoltaics. Here, this concept is extended to hybrid halide perovskite-based materials. In situ time-resolved grazing incidence wide-angle X-ray scattering measurements performed during spin coating reveal that organic gelators beneficially influence the nucleation and growth of the perovskite precursor phase. This can be exploited for the fabrication of planar n-i-p heterojunction devices with MAPbI3 (MA = CH3NH3+) that display a performance that not only is enhanced by ≈25% compared to solar cells where the active layer is produced without the use of a gelator but that also features a higher stability to moisture and a reduced hysteresis. Most importantly, the presented approach is straightforward and simple, and it provides a general method to render the film formation of hybrid perovskites more reliable and robust, analogous to the control that is afforded by these additives in the processing of commodity “plastics.”

  10. Microbial-enzymatic-hybrid biological fuel cell with optimized growth conditions for Shewanella oneidensis DSP-10.

    Science.gov (United States)

    Roy, Jared N; Luckarift, Heather R; Sizemore, Susan R; Farrington, Karen E; Lau, Carolin; Johnson, Glenn R; Atanassov, Plamen

    2013-07-10

    In this work we present a biological fuel cell fabricated by combining a Shewanella oneidensis microbial anode and a laccase-modified air-breathing cathode. This concept is devised as an extension to traditional biochemical methods by incorporating diverse biological catalysts with the aim of powering small devices. In preparing the biological fuel cell anode, novel hierarchical-structured architectures and biofilm configurations were investigated. A method for creating an artificial biofilm based on encapsulating microorganisms in a porous, thin film of silica was compared with S. oneidensis biofilms that were allowed to colonize naturally. Results indicate comparable current and power densities for artificial and natural biofilm formations, based on growth characteristics. As a result, this work describes methods for creating controllable and reproducible bio-anodes and demonstrates the versatility of hybrid biological fuel cells.

  11. On the Fracture Toughness and Crack Growth Resistance of Bio-Inspired Thermal Spray Hybrid Composites

    Science.gov (United States)

    Resnick, Michael Murray

    the values of a real nacre. Although, the fracture toughness was primary property of this study and the values were well matched, the fracture behavior found to be somewhat different between the hybrid composite and nacre. In particular, the hybrid composite was unable to exhibit any significant toughness under slow crack growth conditions, which is the most attractive feature of nacre. This thesis focuses on first investigating the toughness in the sprayed hybrid composites by using standard resistance curve (R-curve) measurements. The study then focused on developing thermal spray modified hybrid composites with improved toughness, as well as with higher application temperatures, beyond the limitation of epoxy.

  12. Genomics Mechanisms of Carbon Allocation and Partitioning in Poplar

    Energy Technology Data Exchange (ETDEWEB)

    Kirst, Matias; Peter, Gary; Martin, Timothy

    2009-07-30

    The genetic control of carbon allocation and partitioning in woody perennial plants is poorly understood despite its importance for carbon sequestration. It is also unclear how environmental cues such as nitrogen availability impact the genes that regulate growth, and biomass allocation and wood composition in trees. To address these questions we phenotyped 396 clonally replicated genotypes of an interspecific pseudo-backcross pedigree of Populus for wood composition and biomass traits in above and below ground organs. The loci that regulate growth, carbon allocation and partitioning under two nitrogen conditions were identified, defining the contribution of environmental cues to their genetic control. Fifty-seven quantitative trait loci (QTL) were identified for twenty traits analyzed. The majority of QTL are specific to one of the two nitrogen treatments, demonstrating significant nitrogen-dependent genetic control. A highly significant genetic correlation was observed between plant growth and lignin/cellulose composition, and QTL co-localization identified the genomic position of potential pleiotropic regulators. Gene expression analysis of all poplar genes was also characterized in differentiating xylem, whole-roots and developing leaves of 192 of the segregating population. By integrating the QTL and gene expression information we identified genes that regulate carbon partitioning and several biomass growth related properties. The work developed in this project resulted in the publication of three book chapters, four scientific articles (three others currently in preparation), 17 presentations in international conferences and two provisional patent applications.

  13. Early growth performance of full-sib Acacia auriculiformis x Acacia mangium F1 hybrid progenies at three different sites

    Science.gov (United States)

    Shah Aimin, Atirah Abdullah; Abdullah, Mohd Zaki; Muhammad, Norwati; Ratnam, Wickneswari

    2014-09-01

    Field trials of 14 full sib Acacia auriculiformis x Acacia mangium F1 hybrid progenies were evaluated for growth performance at three sites (Bintulu, Mentakab and Segamat). Results indicated that there were significant differences (p> 0.05) for diameter breast height (Dbh) and total height (Ht) among the progenies and different sites. Superior progenies have been identified for future tree selection and improvement.

  14. Study on Poplar Industrialization in Jiangsu: (2) Present Status and Problems of Poplar Industrialization

    Institute of Scientific and Technical Information of China (English)

    SHEN Wenxing; ZHOU Dingguo; XU Xinping

    2006-01-01

    This paper lists the existing main problems that poplar industry faces in Jiangsu and analyses the causes and the activities of different industry related to management institution and system according to the factors of knowledge infrastructure, institutional setups, government policies and production structure.

  15. Genetic Modification of Short Rotation Poplar Biomass Feedstock for Efficient Conversion to Ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Dinus, R.J.

    2000-08-30

    The Bioenergy Feedstock Development Program, Environmental Sciences Division, Oak Ridge National Laboratory is developing poplars (Populus species and hybrids) as sources of renewable energy, i.e., ethanol. Notable increases in adaptability, volume productivity, and pest/stress resistance have been achieved via classical selection and breeding and intensified cultural practices. Significant advances have also been made in the efficiencies of harvesting and handling systems. Given these and anticipated accomplishments, program leaders are considering shifting some attention to genetically modifying feedstock physical and chemical properties, so as to improve the efficiency with which feedstocks can be converted to ethanol. This report provides an in-depth review and synthesis of opportunities for and feasibilities of genetically modifying feedstock qualities via classical selection and breeding, marker-aided selection and breeding, and genetic transformation. Information was collected by analysis of the literature, with emphasis on that published since 1995, and interviews with prominent scientists, breeders, and growers. Poplar research is well advanced, and literature is abundant. The report therefore primarily reflects advances in poplars, but data from other species, particularly other shortrotation hardwoods, are incorporated to fill gaps. An executive summary and recommendations for research, development, and technology transfer are provided immediately after the table of contents. The first major section of the report describes processes most likely to be used for conversion of poplar biomass to ethanol, the various physical and chemical properties of poplar feedstocks, and how such properties are expected to affect process efficiency. The need is stressed for improved understanding of the impact of change on both overall process and individual process step efficiencies. The second part documents advances in trait measurement instrumentation and methodology

  16. Short rotation coppice culture of willows and poplars as energy crops on metal contaminated agricultural soils.

    Science.gov (United States)

    Ruttens, Ann; Boulet, Jana; Weyens, Nele; Smeets, Karen; Adriaensen, Kristin; Meers, Erik; Van Slycken, Stijn; Tack, Filip; Meiresonne, Linda; Thewys, Theo; Witters, Nele; Carleer, Robert; Dupae, Joke; Vangronsveld, Jaco

    2011-01-01

    Phytoremediation, more precisely phytoextraction, has been placed forward as an environmental friendly remediation technique, that can gradually reduce increased soil metal concentrations, in particular the bioavailable fractions. The aim of this study was to investigate the possibilities of growing willows and poplars under short rotation coppice (SRC) on an acid, poor, sandy metal contaminated soil, to combine in this way soil remediation by phytoextraction on one hand, and production of biomass for energy purposes on the other. Above ground biomass productivities were low for poplars to moderate for willows, which was not surprising, taking into account the soil conditions that are not very favorable for growth of these trees. Calculated phytoextraction efficiency was much longer for poplars than these for willows. We calculated that for phytoextraction in this particular case it would take at least 36 years to reach the legal threshold values for cadmium, but in combination with production of feedstock for bioenergy processes, this type of land use can offer an alternative income for local farmers. Based on the data of the first growing cycle, for this particular case, SRC of willows should be recommended.

  17. Growth performance of selected eucalypt hybrid clones for SRWC in central and southern Italy

    Directory of Open Access Journals (Sweden)

    Giovanni Mughini

    2014-06-01

    Full Text Available Normal 0 14 false false false IT X-NONE X-NONE st1\\:*{behavior:url(#ieooui } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabella normale"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";} Eucalypt short-rotation woody crop (SRWC is becoming an attractive option for energy biomass in Mediterranean dry environments. The present study is aimed at assessing growth performance of selected eucalypt hybrid clones for SRWC in three Italian sites (Massama, Sardinia; Mirto, Calabria; Rome, Latium compared with Eucalyptus camaldulensis, the most commonly cultivated eucalypt species in Italy. The study identified eucalypt clones with stable and high performance between several alternatives. Results pointed out the declining growth performance observed in the second rotation compared with the first cycle. This is due to the cultivation model, age rotation and harvesting method adopted, which negatively affect the available soil nutrients’ content. The clone/site interaction as for basal area growth at the three investigated sites, suggests a significantly different clones’ performance among sites. Viglio and Velino clones showed the best overall performance and are suggested to be used over the large scale SRWC in central and southern Italy.

  18. Differential expression profiles of poplar MAP kinase kinases in response to abiotic stresses and plant hormones, and overexpression of PtMKK4 improves the drought tolerance of poplar.

    Science.gov (United States)

    Wang, Lei; Su, Hongyan; Han, Liya; Wang, Chuanqi; Sun, Yanlin; Liu, Fenghong

    2014-07-15

    Mitogen-activated protein kinase (MAPK) cascades are universal signal transduction modules that play essential roles in plant growth, development and stress response. MAPK kinases (MAPKKs), which link MAPKs and MAPKK kinases (MAPKKKs), are integral in mediating various stress responses in plants. However, to date few data about the roles of poplar MAPKKs in stress signal transduction are available. In this study, we performed a systemic analysis of poplar MAPKK gene family expression profiles in response to several abiotic stresses and stress-associated hormones. Furthermore, Populus trichocarpa MAPKK4 (PtMKK4) was chosen for functional characterization. Transgenic analysis showed that overexpression of the PtMKK4 gene remarkably enhanced drought stress tolerance in the transgenic poplar plants. The PtMKK4-overexpressing plants also exhibited much lower levels of H2O2 and higher antioxidant enzyme activity after exposure to drought stress compared to the wide type lines. Besides, some drought marker genes including PtP5CS, PtSUS3, PtLTP3 and PtDREB8 exhibited higher expression levels in the transgenic lines than in the wide type under drought conditions. This study provided valuable information for understanding the putative functions of poplar MAPKKs involved in important signaling pathways under different stress conditions.

  19. RNA-SEQ reveals transcriptional level changes of poplar roots in different forms of nitrogen treatments

    Directory of Open Access Journals (Sweden)

    Chunpu eQu

    2016-02-01

    Full Text Available Poplar has emerged as a model plant for understanding molecular mechanisms of tree growth, development and response to environment. Long-term application of different forms of nitrogen (such as NO3--N and NH4+-N may cause morphological changes of poplar roots; however, the molecular level changes are still not well known. In this study, we analyzed the expression profiling of poplar roots treated by three forms of nitrogen: S1 (NH4+, S2 (NH4NO3 and S3 (NO3- by using RNA-SEQ technique. We found 463 genes significantly differentially expressed in roots by different N treatments, of which a total of 116 genes were found to differentially express between S1 and S2, 173 genes between S2 and S3, and 327 genes between S1 and S3. A cluster analysis shows significant difference in many transcription factor families and functional genes family under different N forms. Through an analysis of Mapman metabolic pathway, we found that the significantly differentially expressed genes are associated with fermentation, glycolysis and tricarboxylic acid cycle (TCA, secondary metabolism, hormone metabolism, and transport processing. Interestingly, we did not find significantly differentially expressed genes in N metabolism pathway, mitochondrial electron transport / ATP synthesis and mineral nutrition. We also found abundant candidate genes (20 transcription factors and 30 functional genes regulating morphology changes of poplar roots under the three N forms. The results obtained are beneficial to a better understanding of the potential molecular and cellular mechanisms regulating root morphology changes under different N treatments.

  20. Expression of multiple resistance genes enhances tolerance to environmental stressors in transgenic poplar (Populus × euramericana 'Guariento'.

    Directory of Open Access Journals (Sweden)

    Xiaohua Su

    Full Text Available Commercial and non-commercial plants face a variety of environmental stressors that often cannot be controlled. In this study, transgenic hybrid poplar (Populus × euramericana 'Guariento' harboring five effector genes (vgb, SacB, JERF36, BtCry3A and OC-I were subjected to drought, salinity, waterlogging and insect stressors in greenhouse or laboratory conditions. Field trials were also conducted to investigate long-term effects of transgenic trees on insects and salt tolerance in the transformants. In greenhouse studies, two transgenic lines D5-20 and D5-21 showed improved growth, as evidenced by greater height and basal diameter increments and total biomass relative to the control plants after drought or salt stress treatments. The improved tolerance to drought and salt was primarily attributed to greater instantaneous water use efficiency (WUEi in the transgenic trees. The chlorophyll concentrations tended to be higher in the transgenic lines under drought or saline conditions. Transformed trees in drought conditions accumulated more fructan and proline and had increased Fv/Fm ratios (maximum quantum yield of photosystem II under waterlogging stress. Insect-feeding assays in the laboratory revealed a higher total mortality rate and lower exuviation index of leaf beetle [Plagiodera versicolora (Laicharting] larvae fed with D5-21 leaves, suggesting enhanced insect resistance in the transgenic poplar. In field trials, the dominance of targeted insects on 2-year-old D5-21 transgenic trees was substantially lower than that of the controls, indicating enhanced resistance to Coleoptera. The average height and DBH (diameter at breast height of 2.5-year-old transgenic trees growing in naturally saline soil were 3.80% and 4.12% greater than those of the control trees, but these increases were not significant. These results suggested that multiple stress-resistance properties in important crop tree species could be simultaneously improved, although

  1. 杨木及其刨花板炭化制取木酢液的比较研究%Comparative Analysis of Wood Vinegar Produced by Carbonization of Poplar and Its Particleboard

    Institute of Scientific and Technical Information of China (English)

    马君; 于志明; 黄志义

    2011-01-01

    [目的]探求回收利用废旧刨花板的方法.[方法]采用电加热炭化炉对杨木刨花板及杨木加热炭化,比较杨木刨花板和杨木在炭化热解过程中产物收率以及物理化学性质.[结果]由于受原料形态及刨花板中脲醛树脂胶的影响,杨木刨花板酢液的收率低于杨木酢液,pH高于杨木酢液.GC/MS成分分析结果表明,杨木创花板酢液中存在较多含氮成分.[结论]杨木刨花板酢液中含有丰富的含氮物质,在农林生产中可以作为氮肥促进植物生长.%[Objective] The research aimed to explore the methods of recycling waste particleboard. [Method] Carbonized poplar particle-board and poplar were treated with electric heating furnace. The yield of wood vinegar and difference between the physical and chemical properties in the carbonization process of poplar particleboard and poplar were compared. [ Result ] Poplar particleboard vinegar yield was lower than that of poplar vinegar and pH of poplar particleboard vinegar was higher than that of polar vinegar, which might be due to the different materials and the effects of UF adhesives. The gas chromatography and mass spectrometry analysis showed the existence of much N in the poplar particleboard vinegar. [ Conclusion] Poplar particleboard vinegar was rich of substance with nitrogen, which could be used to promote the growth of plants as fertilizer nitrogen.

  2. The Growth Analysis in the Kernel Filling Process of K-Type Hybrid 901 and Its Parent Wheat

    Institute of Scientific and Technical Information of China (English)

    GONG Yue-hua; LIU Ying-zhou; GAO Jun-feng

    2005-01-01

    Using Matlab software, the grain filling process of hybrid wheat 901 and its parents was fitted by Richards equation W = A/(1 +Be-kt in order to study the characteristics of grain filling of the hybrid. The active grain growth period of the hybrid was 6 d longer than that of Shaan 229, and its final grain weight (43.7 g/1000 grains) was higher than that of Shaan229 (36.3 g/1 000 grains). N values of 901 and R205 were both less than 1, and their grain growth was faster in the early filling stage, while slower in the middle-late stage. N value of Shaan 229 was >1, and its growth was slower in the early stage and faster in the middle stage. The period of early stage of 901 was shorter and of middle-late stage was longer. The situation of Shaan 229 was totally reversed. For parents, the father plant R205 was similar to hybrid wheat 901, whereas its mother plant K3314A similar to Shaan 229. It has been found that Richards equation was more suitable for fitting the grain filling process of wheat than Logistic equation.

  3. Interaction of drought and ozone exposure on isoprene emission from extensively cultivated poplar.

    Science.gov (United States)

    Yuan, Xiangyang; Calatayud, Vicent; Gao, Feng; Fares, Silvano; Paoletti, Elena; Tian, Yuan; Feng, Zhaozhong

    2016-10-01

    The combined effects of ozone (O3 ) and drought on isoprene emission were studied for the first time. Young hybrid poplars (clone 546, Populus deltoides cv. 55/56 x P. deltoides cv. Imperial) were exposed to O3 (charcoal-filtered air, CF, and non-filtered air +40 ppb, E-O3 ) and soil water stress (well-watered, WW, and mild drought, MD, one-third irrigation) for 96 days. Consistent with light-saturated photosynthesis (Asat ), intercellular CO2 concentration (Ci ) and chlorophyll content, isoprene emission depended on drought, O3 , leaf position and sampling time. Drought stimulated emission (+38.4%), and O3 decreased it (-40.4%). Ozone increased the carbon cost per unit of isoprene emission. Ozone and drought effects were stronger in middle leaves (13th-15th from the apex) than in upper leaves (6th-8th). Only Asat showed a significant interaction between O3 and drought. When the responses were up-scaled to the entire-plant level, however, drought effects on total leaf area translated into around twice higher emission from WW plants in clean air than in E-O3 . Our results suggest that direct effects on plant emission rates and changes in total leaf area may affect isoprene emission from intensively cultivated hybrid poplar under combined MD and O3 exposure, with important feedbacks for air quality.

  4. Growth, straightness and survival at age 32 in a Pinus strobus x P. wallichiana F1 hybrid population (Experiment 1

    Directory of Open Access Journals (Sweden)

    Ioan Blada

    2013-11-01

    Full Text Available An interspecific factorial hybridization was made, where seven P. strobus female parent trees were mated to four P. wallichiana male trees, in order to transfer genes for resistance to blister-rust from the blue pine to the F1 hybrids. The hybrid seedlings and the open pollinated families of the two parents were three times consecutivelyinoculated with blister-rust. The six years old seedlings were transplanted in the field in the so called Văliug Experiment 1. The experimental design consisted in 28 hybrid full-sib families and two open pollinated families of the parent species. Plantation took place in a complete randomized block design with three blocks, with 6 to 12 seedlings per linear plot and 3 x 3 m spacing. This paper is based on the measurements made at age 32, just after the first thinning. Diameter at breast height, tree height, tree volume, stem straightness and tree survival were the five measured traits. According to ANOVA, significant (p < 0.05 and highly significant (p< 0.001 differences for diameter at breast height, tree height, volume growth rate, stem straightness and tree survival were detected between hybrid families. Highly significant (p < 0.01, p < 0.001 differences were found between eastern white pine female parents for survival, stem straightness and all growth traits, suggestingthat nuclear additive genes are controlling the respective characters. Consequently, high survival or genetic resistance to blister-rust can be found within the P. strobus species even though it is highly susceptible to this pathogen. The P. wallichiana parents exhibited significant additive effects on straightness and breast height diameter, but no significance in height, volume, and tree survival. The contribution of the additive variance to the phenotypic one was 65.7% for diameter, 58.6% for height, 50.5% for volume, 70.4% for stem straightness and 73.4% for tree survival. Hence, additive variance should be employed in a breeding program

  5. Detection of isoform-specific fibroblast growth factor receptors by whole-mount in situ hybridization in early chick embryos.

    Science.gov (United States)

    Nishita, Junko; Ohta, Sho; Bleyl, Steven B; Schoenwolf, Gary C

    2011-06-01

    We have developed "b" and "c" isoform-specific chicken fibroblast growth factor (FGF) receptor 1-3 probes for in situ hybridization. We rigorously demonstrate the specificity of these probes by using both dot blot hybridization and whole-mount in situ hybridization during neurulation and early postneurulation stages, and we compare expression patterns of each of the three isoform-specific probes to one another and to generic probes to each of the three (non-isoform-specific) FGF receptors. We show that the expression pattern of each receptor is represented by the collective expression of each of its two isoforms, with the expression of each FGF receptor being most similar to that of its "c" isoform at two of the three stages studied, and that tissue and stage differences exist in the patterns of expression of the six isoforms. We demonstrate the usefulness of these probes for defining the differential tissue expression of FGF receptor 1-3 isoforms.

  6. Evaluation of relationships between growth rate, tree size, lignocellulose composition and enzymatic saccharification in interspecific Corymbia hybrids and parental taxa.

    Directory of Open Access Journals (Sweden)

    Adam L Healey

    2016-11-01

    Full Text Available In order for a lignocellulosic bioenergy feedstock to be considered sustainable, it must possess a high rate of growth to supply biomass for conversion. Despite the desirability of a fast growth rate for industrial application, it is unclear what effect growth rate has on biomass composition or saccharification. We characterized Klason lignin, glucan, and xylan content with response to growth in Corymbia interspecific F1 hybrid families (HF and parental species C. torelliana (CT and C. citriodora subspecies variegata (CCV and measured the effects on enzymatic hydrolysis from hydrothermally pretreated biomass. Analysis of biomass composition within Corymbia populations found similar amounts of Klason lignin content (19.7-21.3% among parental and hybrid populations, whereas glucan content was clearly distinguished within CCV (52% and HF148 (60% as compared to other populations (28-38%. Multiple linear regression indicates that biomass composition is significantly impacted by tree size measured at the same age, with Klason lignin content increasing with diameter breast height (DBH (+0.12% per cm DBH increase, and glucan and xylan typically decreasing per DBH cm increase (-0.7% and -0.3%, respectively. Polysaccharide content within CCV and HF-148 were not significantly affected by tree size. High-throughput enzymatic saccharification of hydrothermally pretreated biomass found significant differences among Corymbia populations for total glucose production from biomass, with parental CT and hybrids HF-148 and HF-51 generating the highest amounts of glucose (~180 mg/g biomass, respectively, with HF-51 undergoing the most efficient glucan-to-glucose conversion (74%. Based on growth rate, biomass composition, and further optimization of enzymatic saccharification yield, high production Corymbia hybrid trees are potentially suitable for fast-rotation bioenergy or biomaterial production.

  7. Initial effects of quinclorac on the survival and growth of high biomass tree species

    Directory of Open Access Journals (Sweden)

    Joshua P. Adams

    2017-07-01

    Full Text Available Increasingly, short rotation woody crops are being planted for biofuel/biomass production on unused lands or marginal agricultural lands. Many of these plantations occur near agriculture land which is intensively managed including yearly herbicide applications. Herbicide drift from these applications may cause tree stress and decreasing yields impacting potential biomass production. Quinclorac, a rice herbicide, is often cited as a potential source of tree damage and is the focal herbicide of this study. Five planting stocks, including three eastern cottonwood clones, a hybrid poplar clone, and American sycamore, were assessed for herbicide affects and deployed at three sites across south Arkansas. Stocks were exposed to a full rate labeled for rice (3.175 L ha-1, two rates simulating drift (1/100th and 1/10th the full rate, and a no-spray control. Survival of all Populus clones decreased drastically as quinclorac rate increased, while there was little observed effect on American sycamore. Some variability in treatment response among poplars occurred below the full herbicide rate; however, direct spraying a full herbicide rate on poplars resulted in survival rates below 65 percent and negative growth rates due to dieback. Conversely, photosynthetic rates of remaining leaves increased as quinclorac rate increased. Survival and damage scores of American sycamore, regardless of herbicide rate, remained nearly constant.

  8. Influences of Root Zone Restriction and Nitrogen Nutrition on Hybrid Wheat Growth

    Institute of Scientific and Technical Information of China (English)

    ZHANGRONGIAN; SHENZHENGUO; 等

    1997-01-01

    To study the physiological effects of small root zone,plants of a hybrid wheat variety(Triticum aestivum L.cv.Meiyou 4) were grown in small pots(1 litre)or large pots(8 litre) with low nitrogen(50 mg kg-1 soil) and high nitrogen(200 mg kg-1 soil).Restricting root zone decreased dry weight of plants at the stages of stem elongation and flowering ,compared to those of control plants grown in the large pots(P<0.01).Spraying of 6-benzylaminopurine(50 μmol L01) increased dry weight of plants and chlorophyll concentration in leaves. restriction of root zone decreased the concentrations of total nitrogen,chlorophyll and soluble protein in the flag leaf and accelerated senescence of the leaves,Supply of high nitrogen delayed senescence of the flag leaf.The results suggested that the shortage of nutrients ,especially nitrogen deficiency,was the primary reason for the decreased growth of plant in the treatment of root zone restriction.

  9. Growth Mechanism and Morphology of ZnO/eosin-Y Hybrid Thin Films

    Institute of Scientific and Technical Information of China (English)

    MAR(I) Bernabé; SINGH Krishan-Chander; MOLLAR Miguel; MOYA Mónica; RANA Ravi

    2012-01-01

    Thin hybrid films of ZnO/eosin-Y were prepared by electrodeposition at-0.8 and -0.9 V in aqueous and non-aqueous baths at temperatures ranging from 40 to 90 ℃ with dye concentrations of 100 and 400 μmol· L-1.The films were characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM),energy-dispersive X-ray analysis (EDX),and absorption spectroscopy.The films prepared in a non-aqueous bath were non-porous and did not adsorb dye molecules on their surface.However,the films grown in aqueous media were porous in nature and adsorbed dye during the deposition of ZnO.Preferential growth of the film along the (002) face was observed,and the highest crystallinity was achieved when the film was deposited at 60 ℃.The maximum absorption was achieved for the films grown at 60 to 70 ℃,a deposition potential of-0.9 V,and a dye concentration of 100 μmol· L-1.

  10. Hybrid triazoles: Design and synthesis as potential dual inhibitor of growth and efflux inhibition in tuberculosis.

    Science.gov (United States)

    Dixit, Prasad P; Dixit, Prashant P; Thore, Shivajirao N

    2016-01-01

    Efflux inhibition is proven bacterial machinery responsible for removal of bacterial wastage including antibiotics. Recently, efflux inhibitors (EI) have been tested with encouraging results as an adjuvant therapy for treatment of tuberculosis (TB). Although, EI have emerged as innovative approach of treatment for multi drug resistant (MDR) & extensively drug resistant tuberculosis (XDR-TB), toxicity profile limits their wider use. To address this issue, we have attempted synthesizing hybrid molecules those results by combining known EI and triazole. This synthesis was aimed to arrive at structure that possesses pharmacophore from known EI. Synthesized molecules were evaluated as growth inhibitors (GI) and Efflux inhibitor of TB initially against Mycobacterium smegmatis mc(2)155. Pharmacologically active compounds were then tested for their cytotoxicity to further narrow down search. Most active compounds 144, 145, 154 and 163 were then tested for their GEI action against Mycobacterium tuberculosis (Mtb). Synthesized compounds were also tested for their synergistic action with first line and second line anti-TB drugs and ethidium bromide (EtBr). We arrived at compound 135 as most potent dual inhibitor of tuberculosis.

  11. Growth Mechanism of a Hybrid Structure Consisting of a Graphite Layer on Top of Vertical Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Nicolo' Chiodarelli

    2012-01-01

    Full Text Available Graphene and carbon nanotubes (CNTs are both carbon-based materials with remarkable optical and electronic properties which, among others, may find applications as transparent electrodes or as interconnects in microchips, respectively. This work reports on the formation of a hybrid structure composed of a graphitic carbon layer on top of vertical CNT in a single deposition process. The mechanism of deposition is explained according to the thickness of catalyst used and the atypical growth conditions. Key factors dictating the hybrid growth are the film thickness and the time dynamic through which the catalyst film dewets and transforms into nanoparticles. The results support the similarities between chemical vapor deposition processes for graphene, graphite, and CNT.

  12. Yield physiology of short rotation intensively cultured poplars

    Science.gov (United States)

    J. G. Isebrands; N. D. Nelson; D. I. Dickmann; D. A. Michael

    1983-01-01

    An integrated research approach is described for studying yield physiology of short rotation intensively cultured (SRIC) poplar plantations. Branch architecture differs with clone and stand density, but the clonal ranking of important branch characteristics does not change with spacing.

  13. Preliminary Functional-Structural Modeling on Poplar (Salicaceae)

    CERN Document Server

    Liu, Dongxiang; Letort, Véronique; Xing, Meijun; Gang, Yang; Huang, Xinyuan; Cao, Weiqun

    2010-01-01

    Poplar is one of the best fast-growing trees in the world, widely used for windbreak and wood product. Although architecture of poplar has direct impact on its applications, it has not been descried in previous poplar models, probably because of the difficulties raised by measurement, data processing and parameterization. In this paper, the functional-structural model GreenLab is calibrated by using poplar data of 3, 4, 5, 6 years old. The data was acquired by simplifying measurement. The architecture was also simplified by classifying the branches into several types (physiological age) using clustering analysis, which decrease the number of parameters. By multi-fitting the sampled data of each tree, the model parameters were identified and the plant architectures at different tree ages were simulated.

  14. Poplar: A Java Extension for Evolvable Component Integration

    CERN Document Server

    Nyström-Persson, Johan

    2011-01-01

    The Java programming language contains many features that aid component-based software development (CBSD), such as interfaces, visibility levels, and strong support for encapsulation. However, component evolution often causes so-called breaking changes, largely because of the rigidity of component interconnections in the form of explicit method calls and field accesses. We present a Java extension, Poplar, which we are currently developing. In Poplar, inter-component dependencies are expressed using declarative queries; concrete linking code, generated using a planning algorithm, replaces these at compile time. Poplar includes a minimal specification language based on typestate-like protocols and labels, and a lightweight effect system, which ensures the absence of unwanted interference between hand-written code and generated code. We give several examples of fully automatic component integration using Poplar, and demonstrate its potential to simplify object-oriented software development greatly through evolv...

  15. Growth of thick MgB{sub 2} films by impinging-jet hybrid physical-chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Lamborn, D.R. [Department of Chemical Engineering, The Pennsylvania State University, University Park, PA 16802 (United States); Wilke, R.H.T.; Li, Q. [Department of Physics, The Pennsylvania State University, University Park, PA 16802 (United States); Xi, X. [Department of Physics, Department of Materials Science and Engineering, Materials Research Institute, The Pennsylvania State University, University Park, PA 16801 (United States); Snyder, D.W. [Applied Research Laboratory, The Pennsylvania State University, University Park, PA 16802 (United States); Redwing, J.M. [Department of Materials Science and Engineering, Materials Research Institute, The Pennsylvania State University, University Park, PA 16801 (United States)

    2008-01-18

    Thick MgB{sub 2} films are grown using a novel impinging-jet hybrid physical-chemical vapor deposition process. An increased amount of the boron source gas generates high growth rates. Superconducting properties of the thick films are comparable to previous results from other processes, which indicate that this is a promising new process for MgB{sub 2} deposition for coated conductor applications, such as wires and tapes for MRI magnets. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  16. Growth, straightness and survival at age 32 in a Pinus strobus x P. wallichiana F1 hybrid population (Experiment 2

    Directory of Open Access Journals (Sweden)

    Ioan Blada

    2013-07-01

    Full Text Available By using an incomplete factorial mating design between twenty Pinus strobus L. female and seven P. wallichiana Jack. male trees, a number of 34 full-sib families were obtained. The objective of this experiment was to combine the fast growing of the former species with moderately to high resistance to blister rust (Cronartium ribicola Fich. in Rabenh. of the latter one. The hybrid families were artificially inoculated at age two, and field planted at age four. The plantation took place within an old black current (Ribes nigrum L. heavy infected by blister rust. In order to provoke new infections, this time naturally, the pine rows were planted in between the black currant ones. Diameters at breast height, tree height, tree growth rate volume, stem straightness and tree survivals were the traits measured at age 32 from seed. The first trial thinning was simultaneously applied with the present measurements. The average tree survival was 74.8% in hybrids, 8.3% in Pinus strobus and 27.8% in P. wallichiana. Highly significant (p < 0.01 differences were found between hybrid families for all traits except stem straightness. Genetic coefficient of variation at family level was 13.7% for tree volume growth rate and 15.9% for tree survival, but only 2.1% for tree straightness. Broad-sense family heritability estimates were 0.530 for diameter at breast height, 0.596 for stem height, and 0.564 for stem volume growth rate, 0.166 for stem straightness, and 0.539 for tree survivals. Similarly, the individual tree narrow-sense heritability estimates were 0.138 for diameter at breast height, 0.209 for stem height, 0.149 for stem volume growth rate, and 0.022 for stem straightness. If the best 5, 10 and 15 of 34 families were selected, a genetic gain of 17.7%, 13.4% and 10.2%, respectively, may be achieved in tree survival or blister rust resistance. Similarly, if the best 5%, 10% and 15% individuals within the best hybrid families were selected, a genetic gain of

  17. Growth, straightness and survival at age 32 in a Pinus strobus x P. wallichiana F1 hybrid population (Experiment 2

    Directory of Open Access Journals (Sweden)

    Ioan Blada

    2013-05-01

    Full Text Available By using an incomplete factorial mating design between twentyPinus strobus L. female and seven P. wallichiana Jack. male trees, a number of 34 full-sib families were obtained. The objective of this experiment was to combine the fast growing of the former species with moderately to high resistance to blister rust (Cronartium ribicola Fich. in Rabenh. of the latter one. The hybrid families were artificially inoculated at age two, and field planted at age four. The plantation took place within an old black current (Ribes nigrum L. heavy infected by blister rust. In order to provoke new infections, this time naturally, the pine rows were planted in between theblack currant ones. Diameters at breast height, tree height, tree growth rate volume, stem straightness and tree survivals were the traits measured at age 32 from seed. The first trial thinning was simultaneously applied with the present measurements. The average tree survival was 74.8% in hybrids, 8.3% in Pinus strobus and 27.8% in P. wallichiana. Highly significant (p < 0.01 differences were found between hybrid families for all traits except stem straightness. Genetic coefficient of variation at family level was 13.7% fortree volume growth rate and 15.9% for tree survival, but only 2.1% for tree straightness. Broad-sense family heritability estimates were 0.530 for diameter at breast height, 0.596 for stem height, and 0.564 for stem volume growth rate, 0.166 for stem straightness, and 0.539 for tree survivals. Similarly, the individual tree narrow-sense heritability estimates were 0.138 for diameter at breast height, 0.209 for stem height, 0.149 for stem volume growth rate, and 0.022 for stem straightness. If the best 5, 10 and 15 of 34 families wereselected, a genetic gain of 17.7%, 13.4% and 10.2%, respectively, may be achieved in tree survival or blister rust resistance. Similarly, if the best 5%, 10% and 15% individuals within the best hybrid families were selected, a genetic gain of 4

  18. Challenging synergistic activity of poplar-bacteria association for the Cd phytostabilization.

    Science.gov (United States)

    C, Cocozza; D, Trupiano; G, Lustrato; G, Alfano; D, Vitullo; A, Falasca; T, Lomaglio; V, De Felice; G, Lima; G, Ranalli; S, Scippa; R, Tognetti

    2015-12-01

    The synergistic activity between plants and microorganisms may contribute to the implementation of proactive management strategies in the stabilization of contaminated sites, although heavy metals, such as cadmium (Cd), are potentially toxic to them. The aim of this study was to evaluate the degree of tolerance to Cd contamination (supplying twice 40 mg kg(-1) of Cd) in poplar cuttings [clone I-214, P. × euramericana (Dode) Guinier] inoculated or not with two concentrations of Serratia marcescens strain (1 × 10(7) CFU/g and 2 × 10(7) CFU/g of potting mix). The response of the plant-bacteria system to excess Cd was investigated with special reference to the structural traits of plants and the functional efficiency of bacteria. Bacterial colonization and substrate components were previously assessed in order to define the best solution for formulating the experimental plant growth media. The tested plant-bacteria association, especially when bacteria were provided in double concentration, stimulated specific tolerance mechanisms to Cd through the promotion of the poplar growth. Inoculated plants produced larger leaves and increased stem diameter, while roots grew longer and wider in Cd-treated plants. The effect of bacterial inoculum on plant growth traits and metal partitioning in plant organs was assessed in order to define the potential of this poplar clone to be a suitable candidate for phytostabilization of Cd-contaminated soil. The final effect of the inoculation with bacteria, which alleviated the metal load and Cd phytotoxicity due to their bioaccumulation ability, suggests promising phytostabilization potential of these plant-bacteria associations.

  19. Analysis of Upper Hybrid Wave Growth Rates From Measured Electron Distributions; An Encounter With the Source of Auroral Roar

    Science.gov (United States)

    Bounds, S. R.; Kletzing, C. A.; Labelle, J. W.; Samara, M.; Yoon, P. H.

    2005-12-01

    In January of 2003, the High Bandwidth Auroral Rocket (HIBAR) passed through two regions of strong upper hybrid wave emission associated with the approximate matching of the upper hybrid frequency to twice the electron cyclotron frequency (fuh = 2 fce) (Samara 2004) These types of emission are believed to be the source of the HF auroral roar often observed by ground based receivers. The current model theorizes that the free space 0-mode waves observed on the ground are produced through mode conversion of strong emission of Z-mode, or upper hybrid waves. The relativistic electron cyclotron maser exhibits significant growth rates for the Z-mode when the local upper hybrid frequency is just below (~1%) twice the electron cyclotron frequency and with the appropriately unstable electron distribution (Yoon 1996, Yoon 1998, Yoon 2000). Though auroral roar is frequently observed from the ground, the source region has rarely been identified in-situ and even more rarely with sufficient bandwidth to analyze the underlying physical processes. Analysis of the electron distributions from HIBAR show good agreement with the theoretical distributions used by Yoon:98. HIBAR encountered three separate regions where fuh ≍ 2 fce, two of these regions include strong upper hybrid emission, while the third is void of upper hybrid wave activity. The measured particle distributions demonstrate that, in the two regions with wave emission, the relativistic electron cyclotron maser instability produces Z mode wave growth rates at least an order of magnitude greater than the electron collision frequency. In the third region without wave emission, the growth rates are much smaller in both amplitude and the extent of occurance. Samara, M., J. LaBelle, C. A. Kletzing, and S. R. Bounds, Rocket observations of structured upper hybrid wave at fuh=2fce, Geophys. Res. Lett., 31, L22804, doi:10.1029/2004GL021043. Yoon, P. H., A. T. Weatherwax, and T. J. Rosenberg, Lower ionospheric cyclotron maser

  20. Acclimatization process of tofu wastewater on hybrid upflow anaerobic sludge blanket reactor using polyvinyl chloride rings as a growth medium

    Science.gov (United States)

    Yanqoritha, Nyimas; Turmuzi, Muhammad; Derlini

    2017-05-01

    The appropriate process to resolve sewage contamination which have a high organic using anaerobic technology. Hybrid Upflow Anaerobic Sludge Blanket reactor is one of the anaerobic process which consists of a suspended growth media and attached growth media. The reactor has the ability to work at high load rate, sludge produced easily settles, high biomass and the separation of gas, solid and liquid excelent. The purpose of research is to study the acclimatization process in the reactor of Hybrid Upflow Anaerobic Sludge Blanket using a polyvinl chloride ring as the attached growth medium. Reactor of Hybrid Upflow Anaerobic Sludge Blanket use a working volume of 8.6 L. The operation consisting of 3 L suspended reactor and 5.6 L attached reactor. Acclimatization is conducted by providing the substrate from the smallest concentration of COD up to a concentration that will be processed. During the 50th day, acclimatization process assumed the bacteria begin to work, indicated by the dissolved COD and VSS decrease and biogas production. Due to the wastewater containing the high of protein in consequence operational parameters should be controlled and some precautions should be taken to prevent process partially or totally inhibited.

  1. Variation of microfibril angle and its correlation to wood properties in poplars

    Institute of Scientific and Technical Information of China (English)

    FANGSheng-zuo; YANGWen-zhong; FUXiang-xiang

    2004-01-01

    The microfibril angle of seven poplar clones was determined by using X-ray diffraction technique. Microfibril angle,wood basic density, fiber length, fiber width and cellulose content were assessed for every growth ring at breast height for all sample trees. Significant variation in microfibril angle was observed among growth rings. Mean microfibril angle (MFA) at breast height varied from 7.8°to 28° between growth rings with cambial age and showed a consistent pith-to-bark trend of decline angles. Analysis of variance also indicated that there were significant differences in wood basic density, fiber length, fiber width and cellulose content between the growth rings, which had an increasing tendency from pith to bark. Correlations between MFA and examined wood properties were predominantly large and significant negative (α=0.01), and the coefficients were -0.660 for cellulose content, -0.586 for fiber length, -0.516 for fiber width and -0.450 for wood basic density, respectively. Regression analysis with linear and curve estimation indicated that a quadratic function showed the largest R2 and the least standard error for describing the relationships between microfibril angle and measured wood properties, and the correlation coefficients were over -0.45 (n=125). The results from this study suggested that microfibril angle would be a good characteristic for improvement in the future breeding program of poplars.

  2. Evaluation on Salt Tolerance of 25 Species of Poplar Cuttings in Lab

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The growth and morphological characteristics of 25 species of poplar were investigated. The cuttings were cultivated in Hoagland Nutrient Solution, which was made with sodium chloride (NaCl) solutions of concentration of 1.00, 3.00, 4.00, 5.00, 6.00, and 8.00 g/L, respectively. Under such salt stress, the new branch length and biomass accumulation of cuttings decreased as the salt concentration increased. The root/shoot ratio of most of species showed an escalation and then reduction tendency. Under low con...

  3. Sugarcane Aphid Population Growth, Plant Injury, and Natural Enemies on Selected Grain Sorghum Hybrids in Texas and Louisiana.

    Science.gov (United States)

    Brewer, Michael J; Gordy, John W; Kerns, David L; Woolley, James B; Rooney, William L; Bowling, Robert D

    2017-09-06

    In response to the 2013 outbreak of sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae), on sorghum, Sorghum bicolor (L.), in North America, experiments were conducted at three southern U.S. grain sorghum production locations (Corpus Christi, TX; Winnsboro, LA; Rosenberg, TX). The objectives were to authenticate yield decline on susceptible hybrids (2014 and 2015) and to measure aphid population growth and natural enemy prevalence on susceptible and resistant hybrids with similar genetic background (2014). Yield decline on susceptible hybrids (Tx 2752/Tx430 and DKS53-67) was more substantial when aphid population growth accelerated quickly and peaked above 300 aphids per leaf (50 to nearly 100% yield decline). Location and year variation in maximum aphid density and cumulative aphid-days was high, with doubling time values on the susceptible hybrids ranging between 3.9 and 7.9 d. On resistant Tx2752/Tx2783, leaf injury and yield decline were not seen or less severe than on its paired susceptible Tx2752/Tx430. Aphids declined on Tx2752/Tx2783 after initial colony establishment (Corpus Christi) or took about 60% longer to double in population size when compared with Tx2572/Tx430 (Winnsboro). The predominant natural enemy taxa were aphelinid mummies (Hymenoptera: Aphelinidae), ladybird beetles (Coleoptera: Coccinellidae), and sryphid flies (Diptera: Syrphidae), and they were more prevalent during flowering than prior to flowering. They were generally responsive to changes in aphid density of both susceptible and resistant hybrids, but variability points to need for further study. In future research, full season observations should continue as well as more detailed study of potential compatibility of sorghum resistance and biological control. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Continuous steam hydrolysis of tulip poplar

    Energy Technology Data Exchange (ETDEWEB)

    Fieber, C.; Colcord, A.R.; Faass, S.; Muzzy, J.D.; Roberts, R.S.

    1982-08-01

    To produce ethanol from hardwood it is desirable to fractionate the hardwood in order to produce a relatively pure cellulosic pulp for dilute acid hydrolysis. An experimental investigation of continuous steam hydrolysis of tulip poplar wood chips indicates that over 90% of the lignin present can be extracted by 0.1N sodium hydroxide, resulting in a cellulose pulp containing over 90% hexosan. The study was performed using a Stake Technology, Ltd., continuous digester rated at one oven dry ton per hour of wood chips. The yields of hexosans, hexoses, xylan, xylose, lignin, furfural, acetic acid and methanol were determined as a function of residence time and steam pressure in the digester. The information provides a basis for establishing a material and energy balance for a hardwood to ethanol plant.

  5. Effects of bamboo substrate and supplemental feeding on growth and production of hybrid red tilapia fingerlings (Oreochromis mossambicusxOrechromis niloticus)

    NARCIS (Netherlands)

    Keshavanath, P.; Gangadhar, B.; Ramesh, T.J.; Dam, van A.A.; Beveridge, M.C.M.; Verdegem, M.C.J.

    2004-01-01

    Periphyton growing on artificial substrates can increase the production of herbivorous fish in aquaculture ponds. Periphyton may be an alternative or a complement for supplemental feed in fingerling production. Growth and production of hybrid red tilapia (Oreochromis mossambicus x Oreochromis

  6. An Improved FP-Growth with Hybrid MGSO-IRVM Classifier Approach used for Type-2 Diabetes Mellitus Diagnosis

    Directory of Open Access Journals (Sweden)

    K.Vembandasamy

    2015-12-01

    Full Text Available Diabetes is a chronic disease and major problem of morbidity and mortality in developing countries. Type-2 diabetes mellitus (T2DM is the most common type of diabetes and accounts for 90- 95% of all diabetes. In the medical field a predictive data mining association algorithms is used to diagnose the disease at the earlier stage which helps the physicians in the treatment planning procedure. Recently, an improved Frequent Pattern Growth (IFP-Growth with Hybrid Enhanced Artificial Bee Colony-Advanced Kernel Support Vector Machine (EABC-AKSVM classification is introduced with the capability to reduce the number of rules in diagnosing the diabetes. However, the detection accuracy and robust is less. To resolve this problem, an Improved Frequent Pattern Growth (IFP-Growth with Hybrid Modified Glowworm Swarm Optimization-Improved Relevance Vector Machine (MGSO-IRVM Classification based Association Rule Mining (ARM system is proposed in this work to generate effective rules. The proposed work consists of two phases: In first phase, improved FP-growth is proposed to efficiently mine frequent patterns even from uncertain medical database. This is achieved by creating additional array for each item in uncertain transactional database to keep the information of its superitem sets in IFP-tree redundant node generation through this step the computational cost is greatly reduced. In next phase, Hybrid MGSO-IRVM classifier is used to generate the association rules based on the frequent item sets, which avoids rule redundancy and conflicts during the rule mining process. Experimental results show that the proposed model is suitable and alternative model for medical classification to achieve greater accuracy, and to improve medical diagnosis.

  7. BIOLOGICAL MONITORING PROGRAM FOR EAST FORK POPLAR CREEK

    Energy Technology Data Exchange (ETDEWEB)

    ADAMS, S.M.; BEATY, T.W.; BRANDT, C.C.; CHRISTENSEN, S.W.; CICERONE, D.S.

    1998-09-09

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Lear et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity of EFPC. These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumulation studies, and (4) ecological surveys of the periphyton, benthic macroinvertebrate, and fish communities.

  8. BIOLOGICAL MONITORING PROGRAM FOR EAST FORK POPLAR CREEK

    Energy Technology Data Exchange (ETDEWEB)

    ADAMS, S.M.; ASHWOOD, T.L.; BEATY, T.W.; BRANDT, C.C.

    1997-10-24

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y- 12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Lear et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity of EFPC. These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumulation studies, and (4) ecological surveys of the periphyton, benthic macroinvertebrate, and fish communities.

  9. Comparison of gene expression profiles and responses to zinc chloride among inter- and intraspecific hybrids with growth abnormalities in wheat and its relatives.

    Science.gov (United States)

    Takamatsu, Kiyofumi; Iehisa, Julio C M; Nishijima, Ryo; Takumi, Shigeo

    2015-07-01

    Hybrid necrosis is a well-known reproductive isolation mechanism in plant species, and an autoimmune response is generally considered to trigger hybrid necrosis through epistatic interaction between disease resistance-related genes in hybrids. In common wheat, the complementary Ne1 and Ne2 genes control hybrid necrosis, defined as type I necrosis. Two other types of hybrid necrosis (type II and type III) have been observed in interspecific hybrids between tetraploid wheat and Aegilops tauschii. Another type of hybrid necrosis, defined here as type IV necrosis, has been reported in F1 hybrids between Triticum urartu and some accessions of Triticum monococcum ssp. aegilopoides. In types I, III and IV, cell death occurs gradually starting in older tissues, whereas type II necrosis symptoms occur only under low temperature. To compare comprehensive gene expression patterns of hybrids showing growth abnormalities, transcriptome analysis of type I and type IV necrosis was performed using a wheat 38k oligo-DNA microarray. Defense-related genes including many WRKY transcription factor genes were dramatically up-regulated in plants showing type I and type IV necrosis, similarly to other known hybrid abnormalities, suggesting an association with an autoimmune response. Reactive oxygen species generation and necrotic cell death were effectively inhibited by ZnCl2 treatment in types I, III and IV necrosis, suggesting a significant association of Ca(2+) influx in upstream signaling of necrotic cell death in wheat hybrid necrosis.

  10. Improvement of uniformity in cultivation environment and crop growth rate by hybrid control of air flow devices

    Institute of Scientific and Technical Information of China (English)

    BAEK Min-Seon; KWON Sook-Youn; LIM Jae-Hyun

    2015-01-01

    A complete control type plant factory has high efficiency in terms of cultivation area by constructing vertical multiple layered cultivation beds. However, it has a problem of irregular crop growth due to temperature deviation at upper and lower beds and increases in energy consumption by a prolonged cultivation period. In this work, air flow rate inside a facility was improved by a hybrid control of air flow devices like air conditioning and air circulation fan with an established wireless sensor network to minimize temperature deviations between upper and lower beds and to promote crop growth. The performance of proposed system was verified with an experimental environment or Case A wherein air conditioning device was operated without a control algorithm and Case B wherein air conditioning and circulation fans were alternatively operated based on the hybrid control algorithm. After planting leafy vegetables under each experimental condition, crops were cultivated for 21 days. As a result, Case B wherein AC (air conditioning) and ACF (air-circulation fan) were alternatively operated based on the hybrid control algorithm showed that fresh mass, number of leaves, and leaf length for the crops grown were increased by 40.6%, 41.1%, and 11.1%, respectively, compared to Case A.

  11. Evaluation of Lower East Fork Poplar Creek Mercury Sources

    Energy Technology Data Exchange (ETDEWEB)

    Watson, David B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Brooks, Scott C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mathews, Teresa J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevelhimer, Mark S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DeRolph, Chris [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Brandt, Craig C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Peterson, Mark J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ketelle, Richard [East Tennessee Technology Park (ETTP), Oak Ridge, TN (United States)

    2016-06-01

    This report summarizes a 3-year research project undertaken to better understand the nature and magnitude of mercury (Hg) fluxes in East Fork Poplar Creek (EFPC). This project addresses the requirements of Action Plan 1 in the 2011 Oak Ridge Reservation-wide Comprehensive Environmental Response, Compensation, and Liability Act Five Year Review (FYR). The Action Plan is designed to address a twofold 2011 FYR issue: (1) new information suggests mobilization of mercury from the upper and lower EFPC streambeds and stream banks is the primary source of mercury export during high-flow conditions, and (2) the current Record of Decision did not address the entire hydrologic system and creek bank or creek bed sediments. To obtain a more robust watershed-scale understanding of mercury sources and processes in lower EFPC (LEFPC), new field and laboratory studies were coupled with existing data from multiple US Department of Energy programs to develop a dynamic watershed and bioaccumulation model. LEFPC field studies for the project focused primarily on quantification of streambank erosion and an evaluation of mercury dynamics in shallow groundwater adjacent to LEFPC and potential connection to the surface water. The approach to the stream bank study was innovative in using imagery from kayak floats’ surveys from the headwaters to the mouth of EFPC to estimate erosion, coupled with detailed bank soil mercury analyses. The goal of new field assessments and modeling was to generate a more holistic and quantitative understanding of the watershed and the sources, flux, concentration, transformation, and bioaccumulation of inorganic mercury (IHg) and methylmercury (MeHg). Model development used a hybrid approach that dynamically linked a spreadsheet-based physical and chemical watershed model to a systems dynamics, mercury bioaccumulation model for key fish species. The watershed model tracks total Hg and MeHg fluxes and concentrations by examining upstream inputs, floodplain

  12. Biomimetic growth of gallic acid-ZnO hybrid assemblies and their applications

    Energy Technology Data Exchange (ETDEWEB)

    Sarker, Nazmul H.; Barnaby, Stacey N. [Fordham University, Department of Chemistry (United States); Fath, Karl R. [City University of New York and Graduate Center, Department of Biology, Queens College (United States); Frayne, Stephen H.; Nakatsuka, Nako; Banerjee, Ipsita A., E-mail: banerjee@fordham.edu [Fordham University, Department of Chemistry (United States)

    2012-03-15

    In this study, we probed the biomimetic formation of gallic acid (GA)-ZnO nanoparticle hybrids. It was found that the morphologies formed were dependent upon pH values, resulting in GA-ZnO hybrids of varying shapes such as micro or nanoplates or fibers. The formed supramolecular GA-ZnO hybrids were found to be luminescent as indicated by confocal microscopy and were utilized for the photocatalytic degradation of the organic dye methylene blue. We also explored the bactericidal effects of the hybrids on Staphylococcus aureus (S. aureus) as well as Escherichia Coli (E. Coli). Thus, we have developed a new class of shape-controlled nanohybrid assemblies via mild, green synthetic methods that may be utilized for photocatalytic degradation for environmental remediation as well as for antibacterial applications.

  13. Photosynthesis and growth response of maize (Zea mays L.) hybrids exposed to cadmium stress.

    Science.gov (United States)

    Akhtar, Tasneem; Zia-Ur-Rehman, Muhammad; Naeem, Asif; Nawaz, Rab; Ali, Shafaqat; Murtaza, Ghulam; Maqsood, Muhammad Aamer; Azhar, Muhammad; Khalid, Hinnan; Rizwan, Muhammad

    2017-02-01

    Cadmium (Cd) is a biologically non-essential heavy metal while the cultivation of Cd-tolerant varieties/hybrids (V) seems the most promising strategy for remediation of Cd-contaminated soils. For this, 24-day-old seedlings of seven maize hybrids, DKC 65-25, DKC 61-25, DKC 919, 23-T-16, 32-B-33, 31-P-41, and Syn hybrid, were grown in hydroponic conditions for 21 additional days in various Cd concentrations (0, 5, 10, and 15 μM). Effects of variety, Cd, and their interaction were highly significant (p ≤ 0.05) for studied plant agronomic and physiological traits except the V × Cd interaction for leaf chlorophyll content, root-shoot length, and root dry weight. The Cd accumulation in root and shoot increased gradually with increasing Cd treatments while copper (Cu), zinc (Zn), and manganese (Mn) uptake was decreased in all hybrids. The reduction in root and shoot biomass and Cd uptake was lower in 32-B-33 and 23-T-16 compared to other hybrids. The highest accumulation of Cu, Zn, and Mn was observed in 32-B-33, DK C65-25, and 31-P-41, respectively. The differential uptake and accumulation of Cd by maize hybrids may be useful in selection and breeding for Cd-tolerant genotypes.

  14. Synthesis of Ag-ZnO core-shell hybrid nanostructures: an optical approach to reveal the growth mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Encina, Ezequiel R.; Perez, Manuel A.; Coronado, Eduardo A., E-mail: coronado@fcq.unc.edu.ar [Universidad Nacional de Cordoba, Departamento de Fisicoquimica, Facultad de Ciencias Quimicas, INFIQC (Argentina)

    2013-06-15

    In this study, Ag-ZnO core-shell hybrid nanostructures (HNs) have been prepared by means of a very simple chemical methodology. In addition, their morphology and extinction properties have been characterized. It was found that the HNs consist in almost spherical Ag nanoparticle cores (mean diameter 56 nm) surrounded by a thin shell formed by small ZnO nanoparticles (mean size 6 nm). The changes in the extinction spectra during the formation of the hybrid nanostructures have been rationalized using electrodynamics simulations applying Mie theory for coated spheres along with the effective medium theory to describe the dielectric constant of the shell. By assuming a formation and growth mechanism of the shell, it was found that these simulations describe not only qualitatively but also quantitatively the changes in the extinction spectra.

  15. Short day-mediated cessation of growth requires the downregulation of AINTEGUMENTALIKE1 transcription factor in hybrid aspen.

    Directory of Open Access Journals (Sweden)

    Anna Karlberg

    2011-11-01

    Full Text Available Day length is a key environmental cue regulating the timing of major developmental transitions in plants. For example, in perennial plants such as the long-lived trees of the boreal forest, exposure to short days (SD leads to the termination of meristem activity and bud set (referred to as growth cessation. The mechanism underlying SD-mediated induction of growth cessation is poorly understood. Here we show that the AIL1-AIL4 (AINTEGUMENTALIKE transcription factors of the AP2 family are the downstream targets of the SD signal in the regulation of growth cessation response in hybrid aspen trees. AIL1 is expressed in the shoot apical meristem and leaf primordia, and exposure to SD signal downregulates AIL1 expression. Downregulation of AIL gene expression by SDs is altered in transgenic hybrid aspen plants that are defective in SD perception and/or response, e.g. PHYA or FT overexpressors. Importantly, SD-mediated regulation of growth cessation response is also affected by overexpression or downregulation of AIL gene expression. AIL1 protein can interact with the promoter of the key cell cycle genes, e.g. CYCD3.2, and downregulation of the expression of D-type cyclins after SD treatment is prevented by AIL1 overexpression. These data reveal that execution of SD-mediated growth cessation response requires the downregulation of AIL gene expression. Thus, while early acting components like PHYA and the CO/FT regulon are conserved in day-length regulation of flowering time and growth cessation between annual and perennial plants, signaling pathways downstream of SD perception diverge, with AIL transcription factors being novel targets of the CO/FT regulon connecting the perception of SD signal to the regulation of meristem activity.

  16. Investigation of Carbohydrate Compositions for Poplar Ⅰ-214 and Chinese Fir

    Institute of Scientific and Technical Information of China (English)

    HUANG Luohua; QIN Tefu; MAGARA Kengo

    2006-01-01

    The carbohydrate compositions of poplar Ⅰ-214 and Chinese fir were investigated by the methods of hydrolysis and HPLC.The result showed that the contents of glucose,xylose and arabinose in poplar Ⅰ-214 are higher than those in Chinese fir,while contents of rhamnose and mannose in poplar Ⅰ-214 are lower than those in Chinese fir.

  17. Characterisation of the willow phenylalanine ammonia-lyase (PAL) gene family reveals expression differences compared with poplar.

    Science.gov (United States)

    de Jong, Femke; Hanley, Steven J; Beale, Michael H; Karp, Angela

    2015-09-01

    Willow is an important biomass crop for the bioenergy industry, and therefore optimal growth with minimal effects of biotic and abiotic stress is essential. The phenylpropanoid pathway is responsible for the biosynthesis of not only lignin but also of flavonoids, condensed tannins, benzenoids and phenolic glycosides which all have a role in protecting the plant against biotic and abiotic stress. All products of the phenylpropanoid pathway are important for the healthy growth of short rotation cropping species such as willow. However, the phenylpropanoid pathway in willow remains largely uncharacterised. In the current study we identified and characterised five willow phenylalanine ammonia-lyase (PAL) genes, which encode enzymes that catalyse the deamination of l-phenylalanine to form trans-cinnamic acid, the entry point into the phenylpropanoid pathway. Willow PAL1, PAL2, PAL3 and PAL4 genes were orthologous to the poplar genes. However no orthologue of PAL5 appears to be present in willow. Moreover, two tandemly repeated PAL2 orthologues were identified in a single contig. Willow PALs show similar sub-cellular localisation to the poplar genes. However, the enzyme kinetics and gene expression of the willow PAL genes differed slightly, with willow PAL2 being more widely expressed than its poplar orthologues implying a wider role for PALs in the production of flavonoids, condensed tannins, benzenoids, and phenolic glycosides, in willow.

  18. Characterisation of the willow phenylalanine ammonia-lyase (PAL) gene family reveals expression differences compared with poplar

    Science.gov (United States)

    de Jong, Femke; Hanley, Steven J.; Beale, Michael H.; Karp, Angela

    2015-01-01

    Willow is an important biomass crop for the bioenergy industry, and therefore optimal growth with minimal effects of biotic and abiotic stress is essential. The phenylpropanoid pathway is responsible for the biosynthesis of not only lignin but also of flavonoids, condensed tannins, benzenoids and phenolic glycosides which all have a role in protecting the plant against biotic and abiotic stress. All products of the phenylpropanoid pathway are important for the healthy growth of short rotation cropping species such as willow. However, the phenylpropanoid pathway in willow remains largely uncharacterised. In the current study we identified and characterised five willow phenylalanine ammonia-lyase (PAL) genes, which encode enzymes that catalyse the deamination of l-phenylalanine to form trans-cinnamic acid, the entry point into the phenylpropanoid pathway. Willow PAL1, PAL2, PAL3 and PAL4 genes were orthologous to the poplar genes. However no orthologue of PAL5 appears to be present in willow. Moreover, two tandemly repeated PAL2 orthologues were identified in a single contig. Willow PALs show similar sub-cellular localisation to the poplar genes. However, the enzyme kinetics and gene expression of the willow PAL genes differed slightly, with willow PAL2 being more widely expressed than its poplar orthologues implying a wider role for PALs in the production of flavonoids, condensed tannins, benzenoids, and phenolic glycosides, in willow. PMID:26070140

  19. Estimation of algal colonization growth on mortar surface using a hybridization of machine learning and metaheuristic optimization

    Indian Academy of Sciences (India)

    THU-HIEN TRAN; NHAT-DUC HOANG

    2017-06-01

    Estimation of the algal colonization growth on fac¸ade structure can provide useful information for the task of building maintenance. This research proposes a machine learning method based on the least squares support vector regression (LS-SVR) for modelling the growth time of the green alga Klebsormidium flaccidum on mortar surfaces. Furthermore, to identify an appropriate set of the LS-SVR hyper-parameters, the flower pollination algorithm (FPA) is employed as an optimization technique. The characteristics of the mortar samples, including surface roughness, porosity, surface pH, carbonated condition and type of cement, are employed as input factors for the analysing process. This study relies on a dataset that records 539 laboratory experiments to establish a hybrid model of the LS-SVR and the FPA. The cross-validation process reveals that the proposed method can successfully capture the functional relationship between the algal colonization growth and its influencing factors with a satisfactory outcome (the coefficient of determination R 2 = 0.94 and the root meansquare error RMSE = 4.55). These facts demonstrate that the hybrid model is a promising tool for assisting the decision-making process in building maintenance planning

  20. Investigating the Role of Extensin Proteins in Poplar Biomass Recalcitrance

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, Margaret Brigham; Decker, Stephen R.; Bedinger, Patricia A.

    2016-04-13

    The biological conversion of cellulosic biomass to biofuel is hindered by cell wall recalcitrance, which can limit the ability of cellulases to access and break down cellulose. The purpose of this study was to investigate whether hydroxyproline-rich cell wall proteins (extensins) are present in poplar stem biomass, and whether these proteins may contribute to recalcitrance. Three classical extensin genes were identified in Populus trichocarpa through bioinformatic analysis of poplar genome sequences, with the following proposed names: PtEXTENSIN1 (Potri.001G019700); PtEXTENSIN2 (Potri.001G020100); PtEXTENSIN3 (Potri.018G050100). Tissue print immunoblots localized the extensin proteins in poplar stems to regions near the vascular cambium. Different thermochemical pretreatments reduced but did not eliminate hydroxyproline (Hyp, a proxy for extensins) from the biomass. Protease treatment of liquid hot water-pretreated poplar biomass reduced Hyp content by a further 16% and increased subsequent glucose yield by 20%. These data suggest that extensins may contribute to recalcitrance in pretreated poplar biomass, and that incorporating protease treatment into pretreatment protocols could result in a small but significant increase in the yield of fermentable glucose.

  1. Interclonal and within-tree variation in wood properties of poplar clones

    Institute of Scientific and Technical Information of China (English)

    FANGSheng-zuo; YANGWen-zhong

    2003-01-01

    The wood basic density, cellulose content and fiber form were investigated for all sample trees at breast height (1.3m) in seven poplar clones, and at 0 (butt), 5.6, 9.6, 13.6, 17.6, 19.6 and 21.6 m for clone Nanlin-95 and Nanlin-895, respectively,for providing information on variation patterns of wood density, fiber characteristics and holocellulose content within trees and among clones. The results showed that significant variations about wood density, cellulose content, fiber diameter and the ratio of fiber length to diameter existed among poplar clones examined. Variance analysis indicated that there were significant differences in wood basic density, fiber length, fiber diameter and cellulose content among the growth rings, which had an increasing tendency along the direction from pith to bark. The significant differences also existed in wood basic density, fiber length and fiber diameter at different tree height. The mean wood basic density had a general increase trend with increasing height of trees and the lowest was found at the base, while fiber length and fiber diameter had a general decline pattern with increasing height of trees and the biggest value was observed at the height of 5.6 m. Regression analysis indicated that the relationship between examined wood properties and growth ring number (cambial age), and the relationship between examined wood properties and tree height can be described by polynomial functions.

  2. Isolation and Identification of Phosphobacteria in Poplar Rhizosphere from Different Regions of China

    Institute of Scientific and Technical Information of China (English)

    LIU Hui; WU Xiao-Qin; REN Jia-Hong; YE Jian-Ren

    2011-01-01

    A few soil microorganisms can convert insoluble forms of phosphorus (P) to an accessible form to increase plant yields. The objectives of this study were to isolate, screen and identify the phosphobacteria, i.e., phosphate-solubilizing bacteria (PSB) and phosphate-mineralizing bacteria (PMB), in some poplar plantations and to select potential microbial inoculants that could increase the P uptake by plants. Seventy four PSB strains and 138 PMB strains were preliminarily screened from 797 colonies isolated from the rhizosphere soil of poplar by the visible decolorization in the National Botanical Research Institute's phosphate growth medium (NBRIP) containing a pH indicator of bromophenol and by the clear/halo zone on yeast malt agar plate, respectively. Then, based on the solubilization of Ca3(PO4)2 in liquid NBRIP medium and the mineralization of lecithin in liquid Menkina medium, 15 PSB strains and 7 PMB strains were further determined for their abilities to solubilize Ca3(PO4)2 and to mineralize lecithin. The results showed that the 15 PSB strains exhibited inorganic P-solubilizing abilities ranging between 376.62 and 669.56 mg L-1 and the 7 PMB strains exhibited organic P-mineralizing abilities varying from 0.32 to 1.56 mg L-1 three days after incubation. Three of PSB strains with the highest P-solubilizing ability, named JW-JS1, JW-JS2 and JW-SX2, were all preliminarily identified as Pseudomonas fluorescens,while two of PMB strains with the highest P-mineralizing ability, named JYZ-SD1 and JYT-JS2, were preliminarily identified as Bacillus cereus and Bacillus subtilis, respectively. All the efficient PSB and PMB strains should be further studied under both pot culture and field conditions to test their beneficial effects on poplar.

  3. Hypoxia Affects Nitrogen Uptake and Distribution in Young Poplar (Populus × canescens Trees.

    Directory of Open Access Journals (Sweden)

    Bin Liu

    Full Text Available The present study with young poplar trees aimed at characterizing the effect of O2 shortage in the soil on net uptake of NO3- and NH4+ and the spatial distribution of the N taken up. Moreover, we assessed biomass increment as well as N status of the trees affected by O2 deficiency. For this purpose, an experiment was conducted in which hydroponically grown young poplar trees were exposed to hypoxic and normoxic (control conditions for 14 days. 15N-labelled NO3- and NH4+ were used to elucidate N uptake and distribution of currently absorbed N and N allocation rates in the plants. Whereas shoot biomass was not affected by soil O2 deficiency, it significantly reduced root biomass and, consequently, the root-to-shoot ratio. Uptake of NO3- but not of NH4+ by the roots of the trees was severely impaired by hypoxia. As a consequence of reduced N uptake, the N content of all poplar tissues was significantly diminished. Under normoxic control conditions, the spatial distribution of currently absorbed N and N allocation rates differed depending on the N source. Whereas NO3- derived N was mainly transported to the younger parts of the shoot, particularly to the developing and young mature leaves, N derived from NH4+ was preferentially allocated to older parts of the shoot, mainly to wood and bark. Soil O2 deficiency enhanced this differential allocation pattern. From these results we assume that NO3- was assimilated in developing tissues and preferentially used to maintain growth and ensure plant survival under hypoxia, whereas NH4+ based N was used for biosynthesis of storage proteins in bark and wood of the trees. Still, further studies are needed to understand the mechanistic basis as well as the eco-physiological advantages of such differential allocation patterns.

  4. Forage growth, yield and quality responses of Napier hybrid grass cultivars to three cutting intervals in the Himalayan foothills

    OpenAIRE

    2015-01-01

    A 3 x 3 factorial study was conducted in the southern foothills of Bhutan to compare 3 cultivars of Napier hybrid grass (Pennisetum purpureum x P. glaucum: Pakchong-1, CO-3 and Giant Napier), at 3 cutting intervals (40, 60 and 80 days), in terms of forage growth, dry matter (DM) yield and crude protein (CP) concentration. The effects of cultivar x cutting interval were significant only on tiller number per plant and leaf:stem ratio (LSR). CO-3 consistently produced the highest tiller number p...

  5. Dysfunction of mitotic cell division at shoot apices triggered severe growth abortion in interspecific hybrids between tetraploid wheat and Aegilops tauschii.

    Science.gov (United States)

    Hatano, Hitoshi; Mizuno, Nobuyuki; Matsuda, Ryusuke; Shitsukawa, Naoki; Park, Pyoyun; Takumi, Shigeo

    2012-06-01

    Common wheat is an allohexaploid species, derived through endoreduplication of an interspecific triploid hybrid produced from a cross between cultivated tetraploid wheat and the wild diploid relative Aegilops tauschii. Hybrid incompatibilities, including hybrid necrosis, have been observed in triploid wheat hybrids. A limited number of A. tauschii accessions show hybrid lethality in triploid hybrids crossed with tetraploid wheat as a result of developmental arrest at the early seedling stage, which is termed severe growth abortion (SGA). Despite the potential severity of this condition, the genetic mechanisms underlying SGA are not well understood. Here, we conducted comparative analyses of gene expression profiles in crown tissues to characterize developmental arrest in triploid hybrids displaying SGA. A number of defense-related genes were highly up-regulated, whereas many transcription factor genes, such as the KNOTTED1-type homeobox gene, which function in shoot apical meristem (SAM) and leaf primordia, were down-regulated in the crown tissues of SGA plants. Transcript accumulation levels of cell cycle-related genes were also markedly reduced in SGA plants, and no histone H4-expressing cells were observed in the SAM of SGA hybrid plants. Our findings demonstrate that SGA shows unique features among other types of abnormal growth phenotypes, such as type II and III necrosis.

  6. Response of the gypsy moth, Lymantria dispar to transgenic poplar, Populus simonii x P. nigra, expressing fusion protein gene of the spider insecticidal peptide and Bt-toxin C-peptide.

    Science.gov (United States)

    Cao, Chuan-Wang; Liu, Gui-Feng; Wang, Zhi-Ying; Yan, Shan-Chun; Ma, Ling; Yang, Chuan-Ping

    2010-01-01

    The response of the Asian gypsy moth Lymantria dispar (L.) (Lepidoptera: Lymantriidae) to a fusion gene consisting of the spider, Atrax robustus Simon (Araneae: Hexanthelidae) ω-ACTX-Ar1 sequence coding for an ω-atracotoxin and a sequence coding for the Bt-toxin C-peptide, expressed in transgenic poplar Populus simonii x P. nigra L. (Malphigiales: Salicaceae) was investigated. Individual performance, feeding selection, midgut proteinase activity and nutrition utilization were monitored. The growth and development of L. dispar were significantly affected by continually feeding on the transgenic poplar, with the larval instars displaying significantly shorter developmental times than those fed on nontransgenic poplar, but pupation was delayed. Mortality was higher in populations fed transgenic poplar leaves, than for larvae fed nontransgenic poplar leaves. The cumulative mortality during all stages of larvae fed transgenic leaves was 92% compared to 16.7% of larvae on nontransgenic leaves. The highest mortality observed was 71.7% in the last larval instar stage. A two-choice test showed that fifth-instar larvae preferred to feed on nontransgenic leaves at a ratio of 1:1.4. Feeding on transgenic leaves had highly significant negative effects on relative growth of larvae, and the efficiency of conversion of ingested and digested food. Activity of major midgut proteinases was measured using substrates TAME and BTEE showed significant increases in tryptase and chymotrypsinlike activity (9.2- and 9.0-fold, respectively) in fifth-instar larvae fed on transgenic leaves over control. These results suggest transgenic poplar is resistant to L. dispar, and the mature L. dispar may be weakened by the transgenic plants due to Bt protoxins activated by elevated major midgut proteinase activity. The new transgenic poplar expressing fusion protein genes of Bt and a new spider insecticidal peptide are good candidates for managing gypsy moth.

  7. Growth, straightness and survival at age 32 in a Pinus strobus x P. wallichiana F1 hybrid population (Experiment 1

    Directory of Open Access Journals (Sweden)

    Ioan Blada

    2013-12-01

    Full Text Available An interspecific factorial hybridization was made, where seven P. strobus female parent trees were mated to four P. wallichiana male trees, in order to transfer genes for resistance to blister-rust from the blue pine to the F1 hybrids. The hybrid seedlings and the open pollinated families of the two parents were three times consecutively inoculated with blister-rust. The six years old seedlings were transplanted in the fi eld in the so called Valiug Experiment 1. The experimental design consisted in 28 hybrid full-sib families and two open pollinated families of the parent species. Plantation took place in a complete randomized block design with three blocks, with 6 to 12 seedlings per linear plot and 3 x 3 m spacing. This paper is based on the measurements made at age 32, just after the fi rst thinning. Diameter at breast height, tree height, tree volume, stem straightness and tree survival were the fi ve measured traits. According to ANOVA, signifi cant (p < 0.05 and highly signifi cant (p < 0.001 differences for diameter at breast height, tree height, volume growth rate, stem straightness and tree survival were detected between hybrid families. Highly signifi cant (p< 0.01, p < 0.001 differences were found between eastern white pine female parents for survival, stem straightness and all growth traits, suggesting that nuclear additive genes are controlling the respective characters. Consequently, high survival or genetic resistance to blister-rust can be found within the P. strobus species even though it is highly susceptible to this pathogen. The P. wallichiana parents exhibited signifi cant additive effects on straightness and breast height diameter, but no signifi cance in height, volume, and tree survival. The contribution of the additive variance to the phenotypic one was 65.7% for diameter, 58.6% for height, 50.5% for volume, 70.4% for stem straightness and 73.4% for tree survival. Hence, additive variance should be employed

  8. Growth, straightness and survival at age 32 in a Pinus strobus x P. wallichiana F1 hybrid population (Experiment 1

    Directory of Open Access Journals (Sweden)

    Ioan Blada

    2013-12-01

    Full Text Available An interspecific factorial hybridization was made, where seven P. strobus female parent trees were mated to four P. wallichiana male trees, in order to transfer genes for resistance to blister-rust from the blue pine to the F1 hybrids. The hybrid seedlings and the open pollinated families of the two parents were three times consecutively inoculated with blister-rust. The six years old seedlings were transplanted in the fi eld in the so called Valiug Experiment 1. The experimental design consisted in 28 hybrid full-sib families and two open pollinated families of the parent species. Plantation took place in a complete randomized block design with three blocks, with 6 to 12 seedlings per linear plot and 3 x 3 m spacing. This paper is based on the measurements made at age 32, just after the fi rst thinning. Diameter at breast height, tree height, tree volume, stem straightness and tree survival were the fi ve measured traits. According to ANOVA, signifi cant (p < 0.05 and highly signifi cant (p < 0.001 differences for diameter at breast height, tree height, volume growth rate, stem straightness and tree survival were detected between hybrid families. Highly signifi cant (p< 0.01, p < 0.001 differences were found between eastern white pine female parents for survival, stem straightness and all growth traits, suggesting that nuclear additive genes are controlling the respective characters. Consequently, high survival or genetic resistance to blister-rust can be found within the P. strobus species even though it is highly susceptible to this pathogen. The P. wallichiana parents exhibited signifi cant additive effects on straightness and breast height diameter, but no signifi cance in height, volume, and tree survival. The contribution of the additive variance to the phenotypic one was 65.7% for diameter, 58.6% for height, 50.5% for volume, 70.4% for stem straightness and 73.4% for tree survival. Hence, additive variance should be employed

  9. Hydrothermal pretreatment conditions to enhance ethanol production from poplar biomass.

    Science.gov (United States)

    Negro, Maria José; Manzanares, Paloma; Ballesteros, Ignacio; Oliva, Jose Miguel; Cabañas, Araceli; Ballesteros, Mercedes

    2003-01-01

    Pretreatment has been recognized as a key step in enzyme-based conversion processes of lignocellulose biomass to ethanol. The aim of this study is to evaluate two hydrothermal pretreatments (steam explosion and liquid hot water) to enhance ethanol production from poplar (Populus nigra) biomass by a simultaneous saccharification and fermentation (SSF) process. The composition of liquid and solid fractions obtained after pretreatment, enzymatic digestibility, and ethanol production of poplar biomass pretreated at different experimental conditions was analyzed. The best results were obtained in steam explosion pretreatment at 210 C and 4 min, taking into account cellulose recovery above 95%, enzymatic hydrolysis yield of about 60%, SSF yield of 60% of theoretical, and 41% xylose recovery in the liquid fraction. Large particles can be used for poplar biomass in both pretreatments, since no significant effect of particle size on enzymatic hydrolysis and SSF was obtained.

  10. The role of phytochrome A and gibberellins in growth under long and short day conditions: Studies in hybrid aspen

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, M.E. [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden). Dept. of Forest Genetics and Plant Physiology

    2000-07-01

    This thesis addresses questions concerning the regulation of growth and, specifically, the cessation of growth in response to short days in deciduous tree species. The model tree used in the studies was hybrid aspen (Populus tremula L. x P. tremuloides Michx.). We have exploited the possibility of transforming this species to modulate the level of expression of target genes using over-expression and antisense techniques. The target genes in the studies were the photoreceptor phytochrome A (phyA) and gibberellin 20-oxidase (GA 20-oxidase), the latter being a highly regulated enzyme involved in the biosynthesis of gibberellins (GAs). The photoreceptor phyA has been implicated in photoperiodic regulation of growth, while GAs may regulate the physiological response further downstream. The endogenous expression of these genes has been investigated in parallel with studies of various plants with ectopic and reduced levels of expression. The main focus has been on the early stages of induction of growth cessation and its physiological and molecular mechanisms. Studies of hybrid aspen plants with an increased or reduced expression of phyA, show this receptor to mediate the photoperiodic regulation of growth. Plants with ectopic expression could not stop growing despite drastically shortened photoperiods, while the antisense plants showed the reverse phenotype, with a higher sensitivity resulting in earlier cessation of growth. The role of GAs in growth inhibition was also addressed using plants with a reduction in GA levels. These plants showed early cessation of growth and dormancy, and thus an increased sensitivity toward daylength. Conversely, plants with increased rates of GA biosynthesis showed increased growth and stopped growing much later. Furthermore, increases in GA biosynthesis, resulting in high levels of GAs have a major impact on growth. Plants with high GA levels have increased elongation and diameter growth, due to higher rates of cell production in the

  11. Hybrid C-nanotubes/Si 3D nanostructures by one-step growth in a dual-plasma reactor

    Science.gov (United States)

    Toschi, Francesco; Orlanducci, Silvia; Guglielmotti, Valeria; Cianchetta, Ilaria; Magni, Corrado; Terranova, Maria Letizia; Pasquali, Matteo; Tamburri, Emanuela; Matassa, Roberto; Rossi, Marco

    2012-06-01

    Hybrid nanostructures consisting of Si polycrystalline nanocones, with an anemone-like termination coated with C-nanotubes bundles, have been generated on a (1 0 0) Si substrate in a dual mode microwave/radio-frequency plasma reactor. The substrate is both heated and bombarded by energetic H ions during the synthesis process. The nanocones growth is explained considering pull of the growing Si nanocrystalline phase along the lines of the electrical field, likely via a molten/recrystallization mechanism. The one-step building of the achieved complex 3D architectures is described in terms of dynamic competition between Si and C nanotubes growth under the peculiar conditions of kinetically driven processes.

  12. Stem taper equations for poplars growing on farmland in Sweden

    Institute of Scientific and Technical Information of China (English)

    Birger Hjelm

    2013-01-01

    We developed a simple polynomial taper equation for poplars growing on former farmland in Sweden and also evaluated the performance of some well-known taper equations.In Sweden there is an increasing interest in the use of poplar.Effective management of poplar plantations for high yield production would be facilitated by taper equations providing better predictions of stem volume than currently available equations.In the study a polynomial stem taper equation with five parameters was established for individual poplar trees growing on former farmland.The outputs of the polynomial taper equation were compared with five published equations.Data for fitting the equations were collected from 69 poplar trees growing at 37 stands in central and southern Sweden (lat.55-60° N).The mean age of the stands was 21 years (range 14-43),the mean density 984 stemsha-1 (198-3,493),and the mean diameter at breast height (outside bark) 25 cm (range 12-40).To verify the tested equations,performance of accuracy and precision diameter predictions at seven points along the stem was closely analyzed.Statistics used for evaluation of the equations indicated that the variable exponent taper equation presented by Kozak (1988) performed best and can be recommended.The stem taper equation by Kozak (1988) recommended in the study is likely to be beneficial for optimising the efficiency and profitability of poplar plantation management.The constructed polynomial equation and the segmented equation presented by Max & Burkhart (1976) were second and third ranked.Due to the statistical complexity of Kozak's equation,the constructed polynomial equation is alternatively recommended when a simple model is requested and larger bias is accepted.

  13. Short-day treatment during the growing period limits shoot growth and increases frost hardiness of hybrid aspen plants in the nursery

    Institute of Scientific and Technical Information of China (English)

    Zhang Gang; Jaana Luoranen; Heikki Smolander

    2007-01-01

    In Finland, under nursery conditions hybrid aspen may continue their shoot growth until early September. Thus,frost hardening is usually delayed. To solve this problem, We used a three-week period of short-day (SD) treatment between late July and mid-August. During autumn after frost exposure,frost hardiness (FH) Was assessed three times with a stem-browning test. The resuits showed that after SD treatment shoot growth ceased and FH increased when compared to untreated hybrid aspen. Furthermore,the height of SD-treated hybrid aspen varied much less than that of the control plants. We conclude that SD treatment in the nursery during the growing period can be used as a supplementary method for producing well-hardened and uniform hybrid aspen plants.

  14. Sulfate Metabolites of 4-Monochlorobiphenyl in Whole Poplar Plants

    OpenAIRE

    Zhai, Guangshu; Lehmler, Hans-Joachim; Schnoor, Jerald L.

    2012-01-01

    4-Monochlorobiphenyl (PCB3) has been proven to be transformed into hydroxylated metabolites of PCB3 (OH-PCB3s) in whole poplar plants in our previous work. However, hydroxylated metabolites of PCBs, including OH-PCB3s, as the substrates of sulfotransferases have not been studied in many organisms including plants in vivo. Poplar (Populus deltoides × nigra, DN34) was used to investigate the further metabolism from OH-PCB3s to PCB3 sulfates because it is a model plant and one that is frequently...

  15. Effect of different biochars on Nitrogen uptake in poplar trees

    Science.gov (United States)

    George, Elizabeth; Tonon, Giustino; Scandellari, Francesca

    2014-05-01

    Influence of biochar on soil nitrogen transformation and plant uptake has been reported. This paper presents preliminary results of plant N uptake in poplars by using 15N isotope tracer approach Two types of biochar were applied to two sets of pots containing only sand and each pot received a pre-rooted poplar cutting. Half of the pots were inoculated with commercial mycorrhizal gel and the other half were left without. It is intended to provide information on how biochar, mycorrhiza and root interaction mediate nitrogen uptake and organ allocation.

  16. Controlled growth of carbon nanotube-graphene hybrid materials for flexible and transparent conductors and electron field emitters.

    Science.gov (United States)

    Nguyen, Duc Dung; Tai, Nyan-Hwa; Chen, Szu-Ying; Chueh, Yu-Lun

    2012-01-21

    We report a versatile synthetic process based on rapid heating and cooling chemical vapor deposition for the growth of carbon nanotube (CNT)-graphene hybrid materials where the thickness of graphene and density of CNTs are properly controlled. Graphene films are demonstrated as an efficient barrier layer for preventing poisoning of iron nanoparticles, which catalyze the growth of CNTs on copper substrates. Based on this method, the opto-electronic and field emission properties of graphene integrated with CNTs can be remarkably tailored. A graphene film exhibits a sheet resistance of 2.15 kΩ sq(-1) with a transmittance of 85.6% (at 550 nm), while a CNT-graphene hybrid film shows an improved sheet resistance of 420 Ω sq(-1) with an optical transmittance of 72.9%. Moreover, CNT-graphene films are demonstrated as effective electron field emitters with low turn-on and threshold electric fields of 2.9 and 3.3 V μm(-1), respectively. The development of CNT-graphene films with a wide range of tunable properties presented in this study shows promising applications in flexible opto-electronic, energy, and sensor devices.

  17. 长江滩地杨树人工林主伐年龄的研究%A STUDY ON PRINCIPAL FELLING AGE OF POPLAR PLANTATION ON CHANGJIANG RIVER BEACH

    Institute of Scientific and Technical Information of China (English)

    黄庆丰; 孙启祥; 吴泽民; 项艳

    2002-01-01

    The principal felling age of poplar on Changjiang River beach was studied in Nangen forest farm of Huaining County of Anhui Province.Based on beach altitude,the beach was divided into two site conditions:the higher beach(15-16.5m)and lower beach(14-15m).Moder y=a+b lnA was selected as the growth model of poplar plantation.The yield table of poplar plantation was compiled by growth model.At the same time,the assortment yield table of poplar plantation was compiled based on the univariate volume ratio model.According to volume yield table and assortment yield table,the quantitative maturity age both two sites should be 7 years,technical maturity age of match blocks for higher beach and lower beach were 5 years and 6 years respectively.Economic maturity age was 10-13 years for higher beach (P=10%、8%、6%)and 11-12 years for lower beach (P=10%、8%)on the basis of the maximum net present value.In conclusion,according to the three maturity age and management purposes the principal felling age of poplar plantation should be 10-14 years for higher beach and 8-12 years for lower beach.

  18. Transgenic poplar expressing Arabidopsis YUCCA6 exhibits auxin-overproduction phenotypes and increased tolerance to abiotic stress.

    Science.gov (United States)

    Ke, Qingbo; Wang, Zhi; Ji, Chang Yoon; Jeong, Jae Cheol; Lee, Haeng-Soon; Li, Hongbing; Xu, Bingcheng; Deng, Xiping; Kwak, Sang-Soo

    2015-09-01

    YUCCA6, a member of the YUCCA family of flavin monooxygenase-like proteins, is involved in the tryptophan-dependent IAA biosynthesis pathway and responses to environmental cues in Arabidopsis. However, little is known about the role of the YUCCA pathway in auxin biosynthesis in poplar. Here, we generated transgenic poplar (Populus alba × P. glandulosa) expressing the Arabidopsis YUCCA6 gene under the control of the oxidative stress-inducible SWPA2 promoter (referred to as SY plants). Three SY lines (SY7, SY12 and SY20) were selected based on the levels of AtYUCCA6 transcript. SY plants displayed auxin-overproduction morphological phenotypes, such as rapid shoot growth and retarded main root development with increased root hair formation. In addition, SY plants had higher levels of free IAA and early auxin-response gene transcripts. SY plants exhibited tolerance to drought stress, which was associated with reduced levels of reactive oxygen species. Furthermore, SY plants showed delayed hormone- and dark-induced senescence in detached leaves due to higher photosystem II efficiency and less membrane permeability. These results suggest that the conserved IAA biosynthesis pathway mediated by YUCCA family members exists in poplar.

  19. Phenotypic plasticity, QTL mapping and genomic characterization of bud set in black poplar

    Directory of Open Access Journals (Sweden)

    Fabbrini Francesco

    2012-04-01

    Full Text Available Abstract Background The genetic control of important adaptive traits, such as bud set, is still poorly understood in most forest trees species. Poplar is an ideal model tree to study bud set because of its indeterminate shoot growth. Thus, a full-sib family derived from an intraspecific cross of P. nigra with 162 clonally replicated progeny was used to assess the phenotypic plasticity and genetic variation of bud set in two sites of contrasting environmental conditions. Results Six crucial phenological stages of bud set were scored. Night length appeared to be the most important signal triggering the onset of growth cessation. Nevertheless, the effect of other environmental factors, such as temperature, increased during the process. Moreover, a considerable role of genotype × environment (G × E interaction was found in all phenological stages with the lowest temperature appearing to influence the sensitivity of the most plastic genotypes. Descriptors of growth cessation and bud onset explained the largest part of phenotypic variation of the entire process. Quantitative trait loci (QTL for these traits were detected. For the four selected traits (the onset of growth cessation (date2.5, the transition from shoot to bud (date1.5, the duration of bud formation (subproc1 and bud maturation (subproc2 eight and sixteen QTL were mapped on the maternal and paternal map, respectively. The identified QTL, each one characterized by small or modest effect, highlighted the complex nature of traits involved in bud set process. Comparison between map location of QTL and P. trichocarpa genome sequence allowed the identification of 13 gene models, 67 bud set-related expressional and six functional candidate genes (CGs. These CGs are functionally related to relevant biological processes, environmental sensing, signaling, and cell growth and development. Some strong QTL had no obvious CGs, and hold great promise to identify unknown genes that affect bud set

  20. Above- and Below-ground Biomass, Net Ecosystem Carbon Exchange, and Soil Respiration in a Poplar Populus deltoides Bartr.) stand : Changes after 3 years of Growth under Elevated CO2

    Science.gov (United States)

    Barron-Gafford, G. A.; Grieve, K.; Bil, K.; Kudeyarov, V.; Handley, L.; Murthy, R.

    2003-12-01

    Stands of cottonwood (Populus deltoides Bartr.) trees were grown as a coppiced system under ambient (40 Pa), twice ambient (80 Pa), and three times ambient (120 Pa) partial pressure CO2 for the past three years in the Intensively-managed Forest Mesocosm (IFM) of the Biosphere 2 Center. Over three years Net Ecosystem CO2 exchange (NECE) was measured continuously and in the third year, nine whole trees were harvested from each CO2 treatment over the growing season. Both above- and below-ground parameters were measured. Three years of growth under elevated CO2 showed the expected stimulation in foliar biomass (8.7, 11.9, and 13.1 kg for the 40, 80, and 120 Pa treatments, respectively). Rates of NECE also followed an expected increase with elevated atmospheric CO2 concentrations, with maximum CO2 uptake rates reaching 10.5, 15.6, and 19.6 μ moles m-2 s-1 in the 40, 80, and 120 Pa treatments, respectively. However, above ground woody biomass and root biomass were not much stimulated beyond 80 Pa CO2. Wood/foliage and above/below ground biomass ratios reflect this decline. Under conditions of non-limiting nutrients and water, we found consistent increases in the above/below ground biomass ratio and wood to foliage biomass ratios in the 80 compared to the 40 Pa pCO2. Woody biomass production and the above/below ground biomass ratio were lower under the 120 Pa than any other treatment. Although biomass production did not change appreciably between 80 and 120 Pa CO2 treatments, both substrate induced and in-situ soil respiration values are also significantly higher in the 120Pa treatment, though no differences were present prior to CO2 treatments (Murthy et al. 2003). The unique closed-system operation of the IFM allowed for measures of soil CO2 efflux to be measured at both the soil collar and stand scales using a box model that takes into account all inputs and outputs from the stand. In-situ soil respiration rates increased significantly with increased atmospheric CO2

  1. Smart designing of new hybrid materials based on brushite-alginate and monetite-alginate microspheres: Bio-inspired for sequential nucleation and growth

    OpenAIRE

    2014-01-01

    In this report new hybrid materials based on brushite-alginate and monetite-alginate were prepared by self-assembling alginate chains and phosphate source ions via a gelation process with calcium ions. The alginate served as nanoreactor for nucleation and growth of brushite or/and monetite due to its gelling and swelling properties. The alginate gel framework, the crystalline phase and morphology of formed hybrid biomaterials were shown to be strongly dependent upon the concentration of the p...

  2. Genetic improvement on Chinese shrimp ( Fenneropenaeus chinensis): growth and viability performance in F1 hybrids of different populations

    Science.gov (United States)

    Tian, Yi; Kong, Jie; Li, Wendong; Luan, Sheng; Yang, Cuihua; Wang, Qingyin

    2008-11-01

    Fenneropenaeus chinensis distributed in the Yellow Sea and Bohai Sea of China and the west coast of the Korean Peninsula. Different geographical populations represent potentially different genetic resources. To learn further the characteristics of different geographical population, crosses among two wild and three farmed populations were produced. The two wild populations were from the Yellow Sea and Bohai Sea (WYP), and the west coast of the Korean Peninsula and coast (WKN). The three farmed populations included the offspring of first generation of wild shrimp from coast in Korea (FKN), the Huang Hai (the Yellow Sea in Chinese) No.1 (HH1), and JK98. The phenotypes growth and survival rates of these populations were compared to confirm the feasibility for crossbreeding. The body length (BL), carapace length (CL), carapace width (CW), height of the second and third abdominal segment (HST), width of the second and third abdominal segment (WST), length of the first abdominal segment (LF), length of the last abdominal segment (LL), live body weight (BW), and survival rate were measured. Different combinations were statistically performed with ANOVA and Duncan’s Multiple Range Test. The results show that the survival rate of JK98(♀)×WKN(♂) was the highest, followed by WYP(♀)×WKN(♂), FKN(♀)×WYP(♂), FKN(♀)×HH1(♂) and WYP(♀)×FKN(♂); the body weight of FKN(♀)sxHH1(♂) was the highest, followed by FKN(♀)×WYP(♂), WYP(♀)×WKN(♂), WYP(♀)×FKN(♂) and JK98(♀)×WKN(♂); the total length had the same ranking as the body weight. All growth traits in hybrids JK98(♀)×WKN(♂) were the lowest among all combinations. F1 hybrids had significant difference (P0.05) in other growth traits and survival rate. The results of Duncan’s Multiple Range Test are that BL and CL of JK98(♀)×WKN(♂) were significantly different from the other combinations; HST different from the combination of FKN(♀)×WYP(♂), FKN(♀)×HH1(♂) and WYP

  3. Effects of poplar buds as an alternative to propolis on postharvest diseases control of strawberry fruits.

    Science.gov (United States)

    Yang, Shuzhen; Zhou, Yefeng; Ye, Junli; Fan, Gang; Peng, Litao; Pan, Siyi

    2016-04-01

    Botrytis cinerea and Rhizopus stolonifer, two main postharvest pathogens, cause great loss of strawberry fruits. Here, the effects of poplar buds extracts, a main plant source for Chinese propolis, on disease control were investigated in vitro and in vivo. The HPLC profile of poplar buds ethanol extract (PBEE) was almost identical to that of propolis ethanol extract (PEE), with the active flavonoids identified as pinocembrin, chrysin and galangin. PBEE exhibited similar inhibitory activities on spore germination of both pathogens compared with PEE, and PBEE also strongly inhibited the mycelial growth of the pathogens. In vivo, PBEE could effectively reduce decay of strawberry fruits stored at 13 °C. Although the weight loss was slightly increased, the contents of total soluble solid, titritable acid, vitamin C and total anthocyanins were significantly higher in PBEE treated fruits than those of the control. PBEE had the similar antifungal activity with propolis and had great potential as an alternative to propolis to control strawberry fruits diseases. © 2015 Society of Chemical Industry.

  4. The Oak Ridge Y-12 Plant biological monitoring and abatement program for East Fork Poplar Creek

    Energy Technology Data Exchange (ETDEWEB)

    Loar, J.M.; Adams, S.M.; Allison, L.J.; Giddings, J.M.; McCarthy, J.F.; Southworth, G.R.; Smith, J.G.; Stewart, A.J. (Oak Ridge National Lab., TN (USA); Springborn Bionomics, Inc., Wareham, MA (USA); Oak Ridge National Lab., TN (USA))

    1989-10-01

    In May 1985, a National Pollutant Discharge Elimination System permit was issued for the Oak Ridge Y-12 Plant, a nuclear weapons components production facility located in Oak Ridge, Tennessee, and operated by Martin Marietta Energy Systems, Inc., for the US Department of Energy. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Oak Ridge Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek), in particular, the growth and propagation of fish and aquatic life, as designated by the Tennessee Department of Health and Environment. A second purpose for the BMAP is to document the ecological effects resulting from implementation of a water pollution control program that will include construction of nine new wastewater treatment facilities over the next 4 years. Because of the complex nature of the effluent discharged to East Fork Poplar Creek and the temporal and spatial variability in the composition of the effluent (i.e., temporal variability related to various pollution abatement measures that will be implemented over the next several years and spatial variability caused by pollutant inputs downstream of the Oak Ridge Y-12 Plant), a comprehensive, integrated approach to biological monitoring was developed for the BMAP. 39 refs., 5 figs., 8 tabs.

  5. A metabolic signature of the beneficial interaction of the endophyte paenibacillus sp. isolate and in vitro-grown poplar plants revealed by metabolomics.

    Science.gov (United States)

    Scherling, Christian; Ulrich, Kristina; Ewald, Dietrich; Weckwerth, Wolfram

    2009-08-01

    Metabolic profiling via gas chromatography coupled to mass spectrometry was used to investigate the influence of endophytic bacteria on shoots of in vitro-grown poplar plants free from culturable endophytic bacteria. The results demonstrate that the occurrence of an endophytic Paenibacillus strain strongly affects the composition of the plant metabolites of in vitro-grown poplars. Eleven metabolites were significantly changed between inoculated and non-inoculated poplar plants as determined by two independent experiments. Detected shifts in the primary metabolism of the poplar plants pointed to a mutualistic interaction between bacteria able to fix nitrogen and the host plant with altered nitrogen assimilation patterns. The corresponding metabolic signature comprises increased asparagine and urea levels as well as depleted sugars and organic acids of the tricarboxylic acid cycle. These observations coincide with the fact that the Paenibacillus sp. strain P22 is able to grow without nitrogen in the medium, indicating nitrogen fixation from the air also known from other Paenibacillus spp. In combination with the detected plant-growth-promoting effects of the endophyte Paenibacillus P22, a novel mutualistic interaction is observed.

  6. Hatching time and alevin growth prior to the onset of exogenous feeding in farmed, wild and hybrid Norwegian Atlantic salmon.

    Directory of Open Access Journals (Sweden)

    Monica Favnebøe Solberg

    Full Text Available The onset of exogenous feeding, when juveniles emerge from the gravel, is a critical event for salmonids where early emergence and large size provide a competitive advantage in the wild. Studying 131 farmed, hybrid and wild Norwegian Atlantic salmon families, originating from four wild populations and two commercial strains, we investigated whether approximately 10 generations of selection for faster growth has also resulted in increased somatic growth prior to the onset of exogenous feeding. In addition, we tested whether relaxed selection in farms has allowed for alterations in hatching time between farmed and wild salmon. Across three cohorts, wild salmon families hatched earlier than farmed salmon families, while hybrid families displayed intermediate hatching times. While the observed differences were small, i.e., 1-15 degree-days (0-3 days, as water temperatures were c. 5-6°C, these data suggest additive genetic variation for hatching time. Alevin length prior to exogenous feeding was positively related to egg size. After removal of egg size effects, no systematic differences in alevin length were observed between the wild and farmed salmon families. While these results indicate additive genetic variation for egg development timing, and wild salmon families consistently hatched earlier than farmed salmon families, these differences were so small they are unlikely to significantly influence early life history competition of farmed and wild salmon in the natural environment. This is especially the case given that the timing of spawning among females can vary by several weeks in some rivers. The general lack of difference in size between farmed and wild alevins, strongly suggest that the documented differences in somatic growth rate between wild and farmed Norwegian Atlantic salmon under hatchery conditions are first detectable after the onset of exogenous feeding.

  7. Genome-wide and molecular evolution analyses of the phospholipase D gene family in Poplar and Grape.

    Science.gov (United States)

    Liu, Qi; Zhang, Chiyu; Yang, Yongping; Hu, Xiangyang

    2010-06-18

    The Phospholipase D (PLD) family plays an important role in the regulation of cellular processes in plants, including abscisic acid signaling, programmed cell death, root hair patterning, root growth, freezing tolerance and other stress responses. PLD genes constitute an important gene family in higher plants. However, until now our knowledge concerning the PLD gene family members and their evolutionary relationship in woody plants such as Poplar and Grape has been limited. In this study, we have provided a genome-wide analysis of the PLD gene family in Poplar and Grape. Eighteen and eleven members of the PLD gene family were identified in Poplar and Grape respectively. Phylogenetic and gene structure analyses showed that the PLD gene family can be divided into 6 subgroups: alpha, beta/gamma, delta, epsilon, zeta, and phi, and that the 6 PLD subgroups originated from 4 original ancestors through a series of gene duplications. Interestingly, the majority of the PLD genes from both Poplar (76.5%, 13/17) and Grape (90.9%, 10/11) clustered closely together in the phylogenetic tree to the extent that their evolutionary relationship appears more tightly linked to each other, at least in terms of the PLD gene family, than it does to either Arabidopsis or rice. Five pairs of duplicated PLD genes were identified in Poplar, more than those in Grape, suggesting that frequent gene duplications occurred after these species diverged, resulting in a rapid expansion of the PLD gene family in Poplar. The majority of the gene duplications in Poplar were caused by segmental duplication and were distinct from those in Arabidopsis, rice and Grape. Additionally, the gene duplications in Poplar were estimated to have occurred from 11.31 to 13.76 million years ago, which are later than those that occurred in the other three plant species. Adaptive evolution analysis showed that positive selection contributed to the evolution of the PXPH- and SP-PLDs, whereas purifying selection has driven

  8. Genome-wide and molecular evolution analyses of the phospholipase D gene family in Poplar and Grape

    Directory of Open Access Journals (Sweden)

    Yang Yongping

    2010-06-01

    Full Text Available Abstract Background The Phospholipase D (PLD family plays an important role in the regulation of cellular processes in plants, including abscisic acid signaling, programmed cell death, root hair patterning, root growth, freezing tolerance and other stress responses. PLD genes constitute an important gene family in higher plants. However, until now our knowledge concerning the PLD gene family members and their evolutionary relationship in woody plants such as Poplar and Grape has been limited. Results In this study, we have provided a genome-wide analysis of the PLD gene family in Poplar and Grape. Eighteen and eleven members of the PLD gene family were identified in Poplar and Grape respectively. Phylogenetic and gene structure analyses showed that the PLD gene family can be divided into 6 subgroups: α, β/γ, δ, ε, ζ, and φ, and that the 6 PLD subgroups originated from 4 original ancestors through a series of gene duplications. Interestingly, the majority of the PLD genes from both Poplar (76.5%, 13/17 and Grape (90.9%, 10/11 clustered closely together in the phylogenetic tree to the extent that their evolutionary relationship appears more tightly linked to each other, at least in terms of the PLD gene family, than it does to either Arabidopsis or rice. Five pairs of duplicated PLD genes were identified in Poplar, more than those in Grape, suggesting that frequent gene duplications occurred after these species diverged, resulting in a rapid expansion of the PLD gene family in Poplar. The majority of the gene duplications in Poplar were caused by segmental duplication and were distinct from those in Arabidopsis, rice and Grape. Additionally, the gene duplications in Poplar were estimated to have occurred from 11.31 to 13.76 million years ago, which are later than those that occurred in the other three plant species. Adaptive evolution analysis showed that positive selection contributed to the evolution of the PXPH- and SP-PLDs, whereas

  9. Transgenic manipulation of the metabolism of polyamines in poplar cells

    Science.gov (United States)

    Pratiksha Bhatnagar; Bernadette M. Glasheen; Suneet K. Bains; Stephanie L. Long; Rakesh Minocha; Christian Walter; Subhash C. Minocha

    2001-01-01

    The metabolism of polyamines (putrescine, spermidine, and spermine) has become the target of genetic manipulation because of their significance in plant development and possibly stress tolerance. We studied the polyamine metabolism in non-transgenic (NT) and transgenic cells of poplar (Populus nigra 3 maximowiczii) expressing a...

  10. Investment appraisal of a poplar plantation aged 42 years

    Directory of Open Access Journals (Sweden)

    Keča Ljiljana

    2013-01-01

    Full Text Available Commercial profitability of poplar cultivation was analyzed in an artificial poplar plantation in Serbia. The aim of this study was to validate the invested financial means in the artificial poplar plantation, on the basis of the analysis of costs and receipts during a 42-year rotation, on alluvial semigley, at a discount rate of 12%. Methods of dynamic investment calculation (net present value - NPV, internal rate of return - IRR, benefit-cost method - B/C and payback period - PBP were used. The investigated plantations were established from Populus x euramericana cl. I-214, with a planting spacing of 6 x 3 m. At the calculation discount rate of 12%, the project for the production cycle of 42 years was not cost-effective from the economic aspect. The discount rate of 6% can be accepted in the studied plot because of the better site (alluvial semigley, but the oldness of the stand is unfavourable. For the studied sample plot, IRR was 5.51 %. B/C at r=12% in the study compartment was 0.24. The analysis shows that PBP is practically unacceptable for the investor at the discount rate of 6%. In practice, it is necessary to improve the position of producers in getting financial means for investment in poplar cultivation, so as to stimulate the establishment of artificial poplar plantations, especially in the private sector (on private land. [Projekat Ministarstva nauke Republike Srbije, br. TR 37008, TR 31041 and Value chain of non-wood forest products and its role in development of forestry sector in Serbia

  11. Compensatory growth in hybrid tilapia ( Oreochromis mossambicus ×O. niloticus) reared in seawater, following restricted feeding

    Science.gov (United States)

    Wang, Yan; Cui, Yibo; Yang, Yunxia; Cai, Fasheng

    2004-12-01

    Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0 29.0°C for 8 weeks. The controls were fed to satiation twice a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body weight per day for 4 weeks, and then to satiation for the remainder of the experiment. During the first 4-week period, there was a curvilinear relationship between growth rate and ration size. Fish fed 0.5% and 1.5% rations displayed compensatory growth response of 2 weeks duration during realimentation. The weight-adjusted growth rate of fish fed at 3% ration was not significantly different from that of the controls by the end of the experiment, when none of the treatment groups had caught up in body weight with the controls. Hyperphagia was observed for the first 2 weeks of realimenatation in fish previously fed at 3% ration, but persisted for the whole realimentation period in groups previously fed at 0.5% and 1.5% rations. None of the feed restricted groups showed improved digestibility, feed efficiency, or protein and energy retention efficiency.

  12. Compensatory growth in hybrid tilapia (Oreochromis mossambicus×O.Niloticus) reared in seawater, following restricted feeding

    Institute of Scientific and Technical Information of China (English)

    WANG Yan; CUI Yibo; YANG Yunxia; CAI Fasheng

    2004-01-01

    Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0-29.0℃ for 8 weeks. The controls were fed to satiation twice a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body weight per day for 4 weeks, and then to satiation for the remainder of the experiment. During the first 4-week period, there was a curvilinear relationship between growth rate and ration size. Fish fed 0.5% and 1.5% rations displayed compensatory growth response of 2 weeks duration during realimentation. The weight-adjusted growth rate of fish fed at 3% ration was not significantly different from that of the controls by the end of the experiment, when none of the treatment groups had caught up in body weight with the controls. Hyperphagia was observed for the first 2 weeks of realimenatation in fish previously fed at 3% ration, but persisted for the whole realimentation period in groups previously fed at 0.5% and 1.5% rations. None of the feed restricted groups showed improved digestibility, feed efficiency, or protein and energy retention efficiency.

  13. Genetic improvement on Chinese shrimp (Fenneropenaeuschinensis): growth and viability performance in F1 hybrids of different populations

    Institute of Scientific and Technical Information of China (English)

    TIAN Yi; KONG Jie; LI Wendong; LUAN Sheng; YANG Cuihua; WANG Qingyin

    2008-01-01

    Fenneropenaeus chinensis distributed in the Yellow Sea and Bohai Sea of China and the west coast of the Korean Peninsula. Different geographical populations represent potentially different genetic resources. To learn further the characteristics of different geographical population, crosses among two wild and three farmed populations were produced. The two wild populations were from the Yellow Sea and Bohai Sea (WYP), and the west coast of the Korean Peninsula and coast (WKN). The three farmed populations included the offspring of first generation of wild shrimp from coast in Korea (FKN), the Huang Hai (the Yellow Sea in Chinese) No. 1 (HH 1), and JK98. The phenotypes growth and survival rates of these populations were compared to confirm the feasibility for crossbreeding. The body length (BL), carapace length (CL), carapace width (CW), height of the second and third abdominal segment (HST), width of the second and third abdominal segment (WST), length of the first abdominal segment (LF), length of the last abdominal segment (LL), live body weight (BW), and survival rate were measured. Different combinations were statistically performed with ANOVA and Duncan's Multiple significant difference (P<0.05) in BL, CL, HST, LL, and BW; and insignificant difference (P0.05) in other growth traits and survival rate. The results of Duncan's Multiple Range Test are that BL and CL of was the best combination in all growth traits. Therefore, hybridization can introduce the variation to base populations. The systematic selection program based on additive genetic performance may be more effective than crossbreeding.

  14. Growth of hydroxyapatite on the cellular membrane of the bacterium Bacillus thuringiensis for the preparation of hybrid biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Cervantes, Eric Reyes, E-mail: onomaeric@hotmail.com [Centro de Investigación en Ciencias Microbiológicas, Benemérita Universidad Autónoma de Puebla, Prolongación de la 24 Sur y Ave San Claudio, Ciudad Universitaria, Col San Manuel, C.P. 72570 Puebla, Pue (Mexico); Torres, Maykel González, E-mail: mikegcu@fata.unam.mx [Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Campus Juriquilla, Boulevard Juriquilla 3001, Santiago de Querétaro, Querétaro C.P. 76230 (Mexico); Muñoz, Susana Vargas, E-mail: vmsu@unam.mx [Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Campus Juriquilla, Boulevard Juriquilla 3001, Santiago de Querétaro, Querétaro C.P. 76230 (Mexico); Rosas, Efraín Rubio, E-mail: efrainrubio@yahoo.com [Centro de Investigación en Ciencias Microbiológicas, Benemérita Universidad Autónoma de Puebla, Prolongación de la 24 Sur y Ave San Claudio, Ciudad Universitaria, Col San Manuel, C.P. 72570 Puebla, Pue (Mexico); and others

    2016-01-01

    This study aimed to grow hydroxyapatite (HAp) crystals on the cellular wall of the Gram-positive bacterium Bacillus thuringiensis using a bio-mimetic method. Several strains were phenotypically and genotypically characterized using multilocus sequence typing (MLST) gene markers to differentiate the strains and confirm the identity of the isolated species to guarantee that the selected species was not harmful to human health or the environment. Three of the analyzed strains were selected because they exhibited the best nucleation and growth of HAp on the bacterial surface. This innovative method to grow HAp crystals on a cellular membrane helps to elucidate the mechanisms by which osseous tissue is formed in nature. The optimum concentration for the simulated physiological fluid (SPF) was 1.5 ×. The hybrid materials were characterized by optical microscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). - Highlights: • HAp crystals are grown on the cellular wall of a GP bacteria Bacillus thuringiensis. • The growing was carried out by using a bio-mimetic method. • Hybrid materials were characterized with morphological and spectroscopic techniques. • The reported method allows understanding the mechanisms to produce osseous tissue. • The membrane of Bacillus thuringiensis can grow more HAp than Bacillus halodurans.

  15. 南方地区杨树胶合板材定向培育技术的研究%STUDIES ON DIRECTIVE SILVICULTURE OF POPLAR VENEER GLUED WOOD IN THE SOUTHERN REGION OF CHINA

    Institute of Scientific and Technical Information of China (English)

    方升佐; 吕士行; 徐锡增; 唐罗忠; 曹福亮

    1999-01-01

    Based on the results of more than ten year's scientific research and practice, some key techniques for cultivating poplar veneer glued wood were summarized systematically. The results were as follows: (1)Selecting appropriate poplar clones for various cultivation zones according to their growth rate and wood quality. (2)Choosing good sites being suitable for poplar clone growing (at least SI≥18m). (3)Adopting reasonable planting density which can produce more timbers to meet the need of plywood(the tree spacing should be more than 5m×5m). (4)Using correct planting methods for different soil conditions, however, large seedling with 2-year-old root and 1-year-old stem (seedling height>4m)were advocated. (5)Taking effective measures to tend the stand, the most effective measure was interplanting with crops. (6)Pruning was neccessary to produce non-node timber, but pruning method, pruning intensity and pruning season should be controlled properly. If the 6 measures mentioned above were carried out, the poplar forests with a high yield and high quality could be ensured. In order to provied some theoretical basis for cultivating poplar veneer glued wood, 4 optimum cultivation patterns were also established using the method of two dimensions system.

  16. Shoot Photosynthesis and Root Growth of Hybrid and Conventional Rice Cultivars as Affected by N and K Levels in the Root Zone

    Institute of Scientific and Technical Information of China (English)

    YANGXIAOE; V.ROEMHELD; 等

    1997-01-01

    Root box experiments were conducted to evaluate the effects of N and NK levels in the root zone on shoot photosynthesis and root growth of hybrid an cultivar of rice (Oryza sativa L.) on two paddy soils (clayey and silty).The results showed that dry matter yields in the hybrid and the cultivar were considerably increased by NK supply,bu the effect was greater for the hybrid.Supply of NK in the root zone significantly increased photosynthetic rate of the lower position leaf and the active green leaf area per plant,in which the effects were much more obvious in the hybrid rice than in the cultivar.High NK supply in the root zone stimulated the root growth,and decreased pH and increased the oxidation zone in the rhizosphere in both entries,but to a greater extent in the hybrid .The results indicated that higher NK levels were needed to maintain higher root activity and shoot photosynthetic capacity in rice,particularly in hybrid rice.

  17. Conservation status of white poplar (Populus alba L. and black poplar (Populus nigra L. in the territory of Great War Island

    Directory of Open Access Journals (Sweden)

    Šijačić-Nikolić Mirjana

    2014-01-01

    Full Text Available T he paper describes t he conservation status of white poplar (Populus alba L. and black poplar (Populus nigra L. in the territory of Great War Island. The activities of in situ and ex situ gene pool conservation have been defined in order to preserve and expand the populations of the above species, as carriers of complex wetland forest ecosystems.

  18. Growth of hydroxyapatite on the cellular membrane of the bacterium Bacillus thuringiensis for the preparation of hybrid biomaterials.

    Science.gov (United States)

    Cervantes, Eric Reyes; Torres, Maykel González; Muñoz, Susana Vargas; Rosas, Efraín Rubio; Vázquez, Candelario; Talavera, Rogelio Rodríguez

    2016-01-01

    This study aimed to grow hydroxyapatite (HAp) crystals on the cellular wall of the Gram-positive bacterium Bacillus thuringiensis using a bio-mimetic method. Several strains were phenotypically and genotypically characterized using multilocus sequence typing (MLST) gene markers to differentiate the strains and confirm the identity of the isolated species to guarantee that the selected species was not harmful to human health or the environment. Three of the analyzed strains were selected because they exhibited the best nucleation and growth of HAp on the bacterial surface. This innovative method to grow HAp crystals on a cellular membrane helps to elucidate the mechanisms by which osseous tissue is formed in nature. The optimum concentration for the simulated physiological fluid (SPF) was 1.5×. The hybrid materials were characterized by optical microscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR).

  19. Hybrid vapor phase-solution phase growth techniques for improved CZT(S,Se) photovoltaic device performance

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Liang-Yi; Gershon, Talia S.; Haight, Richard A.; Lee, Yun Seog

    2016-12-27

    A hybrid vapor phase-solution phase CZT(S,Se) growth technique is provided. In one aspect, a method of forming a kesterite absorber material on a substrate includes the steps of: depositing a layer of a first kesterite material on the substrate using a vapor phase deposition process, wherein the first kesterite material includes Cu, Zn, Sn, and at least one of S and Se; annealing the first kesterite material to crystallize the first kesterite material; and depositing a layer of a second kesterite material on a side of the first kesterite material opposite the substrate using a solution phase deposition process, wherein the second kesterite material includes Cu, Zn, Sn, and at least one of S and Se, wherein the first kesterite material and the second kesterite material form a multi-layer stack of the absorber material on the substrate. A photovoltaic device and method of formation thereof are also provided.

  20. Hybrid vapor phase-solution phase growth techniques for improved CZT(S,Se) photovoltaic device performance

    Science.gov (United States)

    Chang, Liang-Yi; Gershon, Talia S.; Haight, Richard A.; Lee, Yun Seog

    2016-12-27

    A hybrid vapor phase-solution phase CZT(S,Se) growth technique is provided. In one aspect, a method of forming a kesterite absorber material on a substrate includes the steps of: depositing a layer of a first kesterite material on the substrate using a vapor phase deposition process, wherein the first kesterite material includes Cu, Zn, Sn, and at least one of S and Se; annealing the first kesterite material to crystallize the first kesterite material; and depositing a layer of a second kesterite material on a side of the first kesterite material opposite the substrate using a solution phase deposition process, wherein the second kesterite material includes Cu, Zn, Sn, and at least one of S and Se, wherein the first kesterite material and the second kesterite material form a multi-layer stack of the absorber material on the substrate. A photovoltaic device and method of formation thereof are also provided.

  1. Over-expression of gsh1 in the cytosol affects the photosynthetic apparatus and improves the performance of transgenic poplars on heavy metal-contaminated soil.

    Science.gov (United States)

    Ivanova, L A; Ronzhina, D A; Ivanov, L A; Stroukova, L V; Peuke, A D; Rennenberg, H

    2011-07-01

    Recent studies of transgenic poplars over-expressing the genes gsh1 and gsh2 encoding γ-glutamylcysteine synthetase (γ-ECS) and glutathione synthetase, respectively, provided detailed information on regulation of GSH synthesis, enzymes activities and mRNA expression. In this experiment, we studied quantitative parameters of leaves, assimilating tissues, cells and chloroplasts, mesophyll resistance for CO(2) diffusion, chlorophyll and carbohydrate content in wild-type poplar and transgenic plants over-expressing gsh1 in the cytosol after 3 years of growth in relatively clean (control) or heavy metal-contaminated soil in the field. Over-expression of gsh1 in the cytosol led to a twofold increase of intrafoliar GSH concentration and influenced the photosynthetic apparatus at different levels of organisation, i.e., leaves, photosynthetic cells and chloroplasts. At the control site, transgenic poplars had a twofold smaller total leaf area per plant and a 1.6-fold leaf area per leaf compared to wild-type controls. Annual aboveground biomass gain was reduced by 50% in the transgenic plants. The reduction of leaf area of the transformants was accompanied by a significant decline in total cell number per leaf, indicating suppression of cell division. Over-expression of γ-ECS in the cytosol also caused changes in mesophyll structure, i.e., a 20% decrease in cell and chloroplast number per leaf area, but also an enhanced volume share of chloroplasts and intercellular airspaces in the leaves. Transgenic and wild poplars did not exhibit differences in chlorophyll and carotenoid content of leaves, but transformants had 1.3-fold fewer soluble carbohydrates. Cultivation on contaminated soil caused a reduction of palisade cell volume and chloroplast number, both per cell and leaf area, in wild-type plants but not in transformants. Biomass accumulation of wild-type poplars decreased in contaminated soil by more than 30-fold, whereas transformants showed a twofold decrease

  2. Genes responsive to elevated CO2 concentrations in triploid white poplar and integrated gene network analysis.

    Directory of Open Access Journals (Sweden)

    Juanjuan Liu

    Full Text Available BACKGROUND: The atmospheric CO2 concentration increases every year. While the effects of elevated CO2 on plant growth, physiology and metabolism have been studied, there is now a pressing need to understand the molecular mechanisms of how plants will respond to future increases in CO2 concentration using genomic techniques. PRINCIPAL FINDINGS: Gene expression in triploid white poplar ((Populus tomentosa ×P. bolleana ×P. tomentosa leaves was investigated using the Affymetrix poplar genome gene chip, after three months of growth in controlled environment chambers under three CO2 concentrations. Our physiological findings showed the growth, assessed as stem diameter, was significantly increased, and the net photosynthetic rate was decreased in elevated CO2 concentrations. The concentrations of four major endogenous hormones appeared to actively promote plant development. Leaf tissues under elevated CO2 concentrations had 5,127 genes with different expression patterns in comparison to leaves under the ambient CO2 concentration. Among these, 8 genes were finally selected for further investigation by using randomized variance model corrective ANOVA analysis, dynamic gene expression profiling, gene network construction, and quantitative real-time PCR validation. Among the 8 genes in the network, aldehyde dehydrogenase and pyruvate kinase were situated in the core and had interconnections with other genes. CONCLUSIONS: Under elevated CO2 concentrations, 8 significantly changed key genes involved in metabolism and responding to stimulus of external environment were identified. These genes play crucial roles in the signal transduction network and show strong correlations with elevated CO2 exposure. This study provides several target genes, further investigation of which could provide an initial step for better understanding the molecular mechanisms of plant acclimation and evolution in future rising CO2 concentrations.

  3. Novel nuclear localization and potential function of insulin-like growth factor-1 receptor/insulin receptor hybrid in corneal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Yu-Chieh Wu

    Full Text Available BACKGROUND: Type I insulin-like growth factor receptor (IGF-1R and insulin receptor (INSR are highly homologous molecules, which can heterodimerize to form an IGF-1R/INSR hybrid (Hybrid-R. The presence and biological significance of the Hybrid-R in human corneal epithelium has not yet been established. In addition, while nuclear localization of IGF-1R was recently reported in cancer cells and human corneal epithelial cells, the function and profile of nuclear IGF-1R is unknown. In this study, we characterized the nuclear localization and function of the Hybrid-R and the role of IGF-1/IGF-1R and Hybrid-R signaling in the human corneal epithelium. METHODOLOGY/PRINCIPLE FINDINGS: IGF-1-mediated signaling and cell growth were examined in a human telomerized corneal epithelial (hTCEpi cell line using co-immunoprecipitation, immunoblotting and cell proliferation assays. The presence of Hybrid-R in hTCEpi and primary cultured human corneal epithelial cells was confirmed by immunofluorescence and reciprocal immunoprecipitation of whole cell lysates. We found that IGF-1 stimulated Akt and promoted cell growth through IGF-1R activation, which was independent of the Hybrid-R. The presence of Hybrid-R, but not IGF-1R/IGF-1R, was detected in nuclear extracts. Knockdown of INSR by small interfering RNA resulted in depletion of the INSR/INSR and preferential formation of Hybrid-R. Chromatin-immunoprecipitation sequencing assay with anti-IGF-1R or anti-INSR was subsequently performed to identify potential genomic targets responsible for critical homeostatic regulatory pathways. CONCLUSION/SIGNIFICANCE: In contrast to previous reports on nuclear localized IGF-1R, this is the first report identifying the nuclear localization of Hybrid-R in an epithelial cell line. The identification of a nuclear Hybrid-R and novel genomic targets suggests that IGF-1R traffics to the nucleus as an IGF-1R/INSR heterotetrameric complex to regulate corneal epithelial homeostatic

  4. Hybrid nanocomposite based on cellulose and tin oxide: growth, structure, tensile and electrical characteristics

    Directory of Open Access Journals (Sweden)

    Suresha K Mahadeva and Jaehwan Kim

    2011-01-01

    Full Text Available A highly flexible nanocomposite was developed by coating a regenerated cellulose film with a thin layer of tin oxide (SnO2 by liquid-phase deposition. Tin oxide was crystallized in solution and formed nanocrystal coatings on regenerated cellulose. The nanocrystalline layers did not exfoliate from cellulose. Transmission electron microscopy and energy dispersive x-ray spectroscopy suggest that SnO2 was not only deposited over the cellulose surface, but also nucleated and grew inside the cellulose film. Current–voltage characteristics of the nanocomposite revealed that its electrical resistivity decreases with deposition time, with the lowest value obtained for 24 h of deposition. The cellulose–SnO2 hybrid nanocomposite can be used for biodegradable and disposable chemical, humidity and biosensors.

  5. Types of tree growth and fruit setting in F1 apple hybrids

    Directory of Open Access Journals (Sweden)

    Radu E. SESTRAS

    1998-08-01

    Full Text Available 1656 F1 hybrid apple seedlings, belonging to 127 combinations, have been screened according to their growing and fruit setting types, as it was phenotypically expressed. LESPINASSE (1977; 1992 amalgamated these two traits into a single one which was named ";ideotype";. The screened F1 individuals have been considered as resembling one of the following four architectural ideotypes of the trees indicated by Lespinasse: columnar, spur, standard and weeping. Different ratios of spur, standard and columnar F1 individuals were obtained depending on genitors and on the fact that a certain genitor had been used as a maternal or paternal partner in direct/reciprocal crosses. The monogenic inheritance of the columnar ideotype, proposed by Kelsey and Brown (1992; Lane (1992, does not seem to be the only genetic mechanism involved in the inheritance of this trait. Our experimental results suggest the polygenic determination of this ideotype as more probable than the monogenic one.

  6. Relationship between trophic component of different poplar strains and occurrence of Saperda poplnea

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    An experimental area of poplar was established in Songyuan of Jilin Province in 1999 for testing the resistance of different poplar stains to Saperda poplnea. Incidence of S. poplnea on ten poplar strains were investigated, and the main trophic component of branches of these poplar trees were measured and analyzed in April 2001. The results showed that there existed significant difference in population size of S. poplnea on different poplar strains, and the branches of these poplar strains have significant difference in nutrient component and content of amino acids. The population size of this pest had a significantly posi-tive correlation with dissolvable total sugar and water content but had no significant correlation with content of total nitrogen and protein nitrogen.

  7. Climate change at northern latitudes: rising atmospheric humidity decreases transpiration, N-uptake and growth rate of hybrid aspen.

    Directory of Open Access Journals (Sweden)

    Arvo Tullus

    Full Text Available At northern latitudes a rise in atmospheric humidity and precipitation is predicted as a consequence of global climate change. We studied several growth and functional traits of hybrid aspen (Populus tremula L.×P. tremuloides Michx. in response to elevated atmospheric humidity (on average 7% over the ambient level in a free air experimental facility during three growing seasons (2008-2010 in Estonia, which represents northern temperate climate (boreo-nemoral zone. Data were collected from three humidified (H and three control (C plots, and analysed using nested linear models. Elevated air humidity significantly reduced height, stem diameter and stem volume increments and transpiration of the trees whereas these effects remained highly significant also after considering the side effects from soil-related confounders within the 2.7 ha study area. Tree leaves were smaller, lighter and had lower leaf mass per area (LMA in H plots. The magnitude and significance of the humidity treatment effect--inhibition of above-ground growth rate--was more pronounced in larger trees. The lower growth rate in the humidified plots can be partly explained by a decrease in transpiration-driven mass flow of NO(3 (- in soil, resulting in a significant reduction in the measured uptake of N to foliage in the H plots. The results suggest that the potential growth improvement of fast-growing trees like aspens, due to increasing temperature and atmospheric CO(2 concentration, might be smaller than expected at high latitudes if a rise in atmospheric humidity simultaneously takes place.

  8. Reproductive, Growth Performance and Nutrient Utilization of Heterobranchus bidorsalis (Geoffroy, 1809 and its Hybrid Clariabranchus Induced with Synthetic Hormone and Pituitary Gland of Heterobranchus bidorsalis

    Directory of Open Access Journals (Sweden)

    M.A. Anetekhai

    2011-01-01

    Full Text Available This study was conducted to assess the reproductive performance, growth rate and nutrient utilization capacities of pure breed Heterobranchus bidorsalis (H. bidorsalis ? x H. bidorsalis ? and its hybrid (H. bidorsalis ? x C. gariepinus ? (Clariabranchus induced with synthetic hormone (ovaprim and pituitary of male and female Heterobranchus bidorsalis. In this study, 3 female Heterobranchus bidorsalis, 3 male Heterobranchus bidorsalis and 3 male Clarias gariepinus were used for the experiment. One female H. bidorsalis induced with ovaprim produced eggs which were divided into two equal halves. Each half was fertilized separately by milt from H. bidorsalis and C. gariepinus to produce pure breed and hybrid, respectively. A similar crossing was done for the female H. bidorsalis induced with Male Pituitary Extract (MPE and Female Pituitary Extract (FPE. Percentage fertilization and hatching rate of pure breed induced with ovaprim were significantly (p<0.05 higher than the other genetic crosses. The highest values for weight gain (5.461.58 g, average daily growth (0.390.11 g and specific growth rate (1.040.16%/day occurred in pure breed induced with MPE. The lowest values for these growth parameters were obtained in the hybrid induced with FPE. Feed intake, protein intake, feed conversion ratio and protein efficiency ratio varied significantly (p<0.05 among the treatments. This study has shown that the pure breeds and hybrids induced with ovaprim and MPE performed better than those induced with FPE. Therefore, they are recommended for commercial aquaculture.

  9. In-situ spectroscopy and nanoscale electronics in superconductor-topological insulator hybrid devices: a combined thin film growth and quantum transport study

    NARCIS (Netherlands)

    Ngabonziza, Prosper

    2016-01-01

    In this dissertation, we presented a combined thin film growth and quantum transport study on superconductor topological insulator hybrid devices. Understanding of the electronic properties of topological insulators (TIs), their preparation in high quality thin film form and their interaction with o

  10. Effects of bamboo substrate and supplemental feeding on growth and production of hybrid red tilapia fingerlings (Oreochromis mossambicusxOrechromis niloticus)

    NARCIS (Netherlands)

    Keshavanath, P.; Gangadhar, B.; Ramesh, T.J.; Dam, van A.A.; Beveridge, M.C.M.; Verdegem, M.C.J.

    2004-01-01

    Periphyton growing on artificial substrates can increase the production of herbivorous fish in aquaculture ponds. Periphyton may be an alternative or a complement for supplemental feed in fingerling production. Growth and production of hybrid red tilapia (Oreochromis mossambicus x Oreochromis niloti

  11. Fatigue Crack Growth Prediction for generalized fiber metal laminates and hybrid materials

    NARCIS (Netherlands)

    Wilson, G.S.

    2013-01-01

    The excellent durability performance of Glare, a thin fiber metal laminate (FML) material system, is now being proven in service. This has motivated work towards the application of FMLs to thicker structures driven by damage tolerance. In order to fully characterize the crack growth life of such mat

  12. Genome Enabled Discovery of Carbon Sequestration Genes in Poplar

    Energy Technology Data Exchange (ETDEWEB)

    Filichkin, Sergei; Etherington, Elizabeth; Ma, Caiping; Strauss, Steve

    2007-02-22

    The goals of the S.H. Strauss laboratory portion of 'Genome-enabled discovery of carbon sequestration genes in poplar' are (1) to explore the functions of candidate genes using Populus transformation by inserting genes provided by Oakridge National Laboratory (ORNL) and the University of Florida (UF) into poplar; (2) to expand the poplar transformation toolkit by developing transformation methods for important genotypes; and (3) to allow induced expression, and efficient gene suppression, in roots and other tissues. As part of the transformation improvement effort, OSU developed transformation protocols for Populus trichocarpa 'Nisqually-1' clone and an early flowering P. alba clone, 6K10. Complete descriptions of the transformation systems were published (Ma et. al. 2004, Meilan et. al 2004). Twenty-one 'Nisqually-1' and 622 6K10 transgenic plants were generated. To identify root predominant promoters, a set of three promoters were tested for their tissue-specific expression patterns in poplar and in Arabidopsis as a model system. A novel gene, ET304, was identified by analyzing a collection of poplar enhancer trap lines generated at OSU (Filichkin et. al 2006a, 2006b). Other promoters include the pGgMT1 root-predominant promoter from Casuarina glauca and the pAtPIN2 promoter from Arabidopsis root specific PIN2 gene. OSU tested two induction systems, alcohol- and estrogen-inducible, in multiple poplar transgenics. Ethanol proved to be the more efficient when tested in tissue culture and greenhouse conditions. Two estrogen-inducible systems were evaluated in transgenic Populus, neither of which functioned reliably in tissue culture conditions. GATEWAY-compatible plant binary vectors were designed to compare the silencing efficiency of homologous (direct) RNAi vs. heterologous (transitive) RNAi inverted repeats. A set of genes was targeted for post transcriptional silencing in the model Arabidopsis system; these include the floral

  13. Improvement of production of high-yield poplar varieties seedlings by mycorrhiza application

    Directory of Open Access Journals (Sweden)

    Galić Zoran A.

    2007-01-01

    Full Text Available Research related to the effects of treatment by mycorrhiza preparations Ectovit, Rhodovit (preparations Symbio-m Ltd., Czech Rep. and their combination on growth of four high-yield poplar clones of Populus deltoides and one variety of Populus x euramericana are presented in this paper. In order to make more accurate assessment of mycorrhiza effect, soil characteristics such as morphology, texture and chemical composition were determined. The study results indicate that mycorrhized cuttings had the same or the better survival in all the study clones compared to the control. The application of the preparation Ectovit and Rhodovit resulted averagely in the first class planting stock of all the study clones. The combination of the preparations Ectovit and Rhodovit produced averagely the first class planting stock only of the clone Populus x euramericana.

  14. Impact of Biofuel Poplar Cultivation on Ground-Level Ozone and Premature Human Mortality Depends on Cultivar Selection and Planting Location.

    Science.gov (United States)

    Ashworth, Kirsti; Wild, Oliver; Eller, Allyson S D; Hewitt, C Nick

    2015-07-21

    Isoprene and other volatile organic compounds emitted from vegetation play a key role in governing the formation of ground-level ozone. Emission rates of such compounds depend critically on the plant species. The cultivation of biofuel feedstocks will contribute to future land use change, altering the distribution of plant species and hence the magnitude and distribution of emissions. Here we use relationships between biomass yield and isoprene emissions derived from experimental data for 29 commercially available poplar hybrids to assess the impact that the large-scale cultivation of poplar for use as a biofuel feedstock will have on air quality, specifically ground-level ozone concentrations, in Europe. We show that the increases in ground-level ozone across Europe will increase the number of premature deaths attributable to ozone pollution each year by up to 6%. Substantial crop losses (up to ∼9 Mt y(-1) of wheat and maize) are also projected. We further demonstrate that these impacts are strongly dependent on the location of the poplar plantations, due to the prevailing meteorology, the population density, and the dominant crop type of the region. Our findings indicate the need for a concerted and centralized decision-making process that considers all aspects of future land use change in Europe, and not just the effect on greenhouse gas emissions.

  15. An Empirical Assessment of Transgene Flow from a Bt Transgenic Poplar Plantation.

    Science.gov (United States)

    Hu, Jianjun; Zhang, Jin; Chen, Xingling; Lv, Jinhui; Jia, Huixia; Zhao, Shutang; Lu, Mengzhu

    2017-01-01

    To assess the possible impact of transgenic poplar plantations on the ecosystem, we analyzed the frequency and distance of gene flow from a mature male transgenic Populus nigra plantation carrying the Bacillus thuringiensis toxin gene (Bt poplar) and the survival of Bt poplar seeds. The resultant Bt poplar seeds occurred at a frequency of ~0.15% at 0 m to ~0.02% at 500 m from the Bt poplar plantation. The germination of Bt poplar seeds diminished within three weeks in the field (germination rate from 68% to 0%) compared to 48% after three weeks of storage at 4°C. The survival rate of seedlings in the field was 0% without any treatment but increased to 1.7% under the addition of four treatments (cleaning and trimming, watering, weeding, and covering with plastic film to maintain moisture) after being seeded in the field for eight weeks. The results of this study indicate that gene flow originating from the Bt poplar plantation occurred at an extremely low level through pollen or seeds under natural conditions. This study provides first-hand field data on the extent of transgene flow in poplar plantations and offers guidance for the risk assessment of transgenic poplar plantations.

  16. The arbuscular mycorrhizal status of poplar clones selected for phytoremediation of soils contaminated with heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Takacs, T.; Radimszky, L.; Nemeth, T. [Research Inst. for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences, Budapest (Hungary)

    2005-04-01

    The aim of this work was to study the colonization of indigenous arbuscular mycorrhizal fungi (AMF) species in fine-roots of poplar clones. Roots of 7 poplar clones were sampled from a 1-year-old trial established at an industrial site strongly polluted with heavy metals at Balatonfuezfoe, Hungary. The poplar clones have shown variable degrees of colonization by AMF, suggesting differential host susceptibility or mycorrhizal dependency. After outplanting the percentage of poplar survival was strongly correlated with the frequency of AMF infection. Two clones that survived at the lowest ratio after outplanting had not been colonized by AMF in contrast to those which survived to a much higher extent. (orig.)

  17. Poplar maintains zinc homeostasis with heavy metal genes HMA4 and PCS1

    Science.gov (United States)

    Adams, Joshua P.; Adeli, Ardeshir; Hsu, Chuan-Yu; Harkess, Richard L.; Page, Grier P.; dePamphilis, Claude W.; Schultz, Emily B.; Yuceer, Cetin

    2011-01-01

    Perennial woody species, such as poplar (Populus spp.) must acquire necessary heavy metals like zinc (Zn) while avoiding potential toxicity. Poplar contains genes with sequence homology to genes HMA4 and PCS1 from other species which are involved in heavy metal regulation. While basic genomic conservation exists, poplar does not have a hyperaccumulating phenotype. Poplar has a common indicator phenotype in which heavy metal accumulation is proportional to environmental concentrations but excesses are prevented. Phenotype is partly affected by regulation of HMA4 and PCS1 transcriptional abundance. Wild-type poplar down-regulates several transcripts in its Zn-interacting pathway at high Zn levels. Also, overexpressed PtHMA4 and PtPCS1 genes result in varying Zn phenotypes in poplar; specifically, there is a doubling of Zn accumulation in leaf tissues in an overexpressed PtPCS1 line. The genomic complement and regulation of poplar highlighted in this study supports a role of HMA4 and PCS1 in Zn regulation dictating its phenotype. These genes can be altered in poplar to change its interaction with Zn. However, other poplar genes in the surrounding pathway may maintain the phenotype by inhibiting drastic changes in heavy metal accumulation with a single gene transformation. PMID:21504875

  18. Multifunctional hybrid coating on titanium towards hydroxyapatite growth: Electrodeposition of tantalum and its molecular functionalization with organophosphonic acids films

    Energy Technology Data Exchange (ETDEWEB)

    Arnould, Christelle; Delhalle, Joseph [Laboratory of Chemistry and Electrochemistry of Surfaces, University of Namur (FUNDP), Rue de Bruxelles 61, B-5000 Namur (Belgium); Mekhalif, Zineb [Laboratory of Chemistry and Electrochemistry of Surfaces, University of Namur (FUNDP), Rue de Bruxelles 61, B-5000 Namur (Belgium)], E-mail: zineb.mekhalif@fundp.ac.be

    2008-07-20

    Titanium and its alloys are base materials used in the dental and orthopaedic fields owing to suitable intrinsic properties: good biocompatibility, high corrosion resistance and excellent mechanical properties. However, the bonding between titanium and bone tissue is not always strong enough and can become a critical problem. In this context, the two main objectives of this paper are the increase of the corrosion resistance and the improvement of the hydroxyapatite (HAp) growth. The surface modification considered here is achieved in three main steps and consists in the elaboration of different inorganic and organic coatings. The first step is the elaboration of electrodeposition of tantalum on the titanium oxide film of a titanium substrate. The second step is the modification of the tantalum oxide coating with organophosphonic acids. The last step is the nucleation and growth of HAP on the outermost layer of the system by immersion in a simulated body fluid. The hybrid coating tantalum oxide/organophosphonic acids/molecular layer is shown to be promising for orthopaedic implants.

  19. Effects of soil contamination by trace elements on white poplar progeny: seed germination and seedling vigour.

    Science.gov (United States)

    Madejón, Paula; Cantos, Manuel; Jiménez-Ramos, María C; Marañón, Teodoro; Murillo, José M

    2015-11-01

    Seed germination is considered a critical phase in plant development and relatively sensitive to heavy metals. White poplar (Populus alba) trees tend to accumulate Cd and Zn in their tissues. We tested if soil contamination can affect P. alba progeny, reduced seed germination and explored the distribution of mineral elements in the seed. For this purpose, fruits and seeds from female P. alba trees were selected from two contaminated and one non-contaminated areas. Seeds from all the sites were germinated using only water or a nutritive solution (in vitro). Concentrations of nutrients and trace elements in the fruits and seeds were analysed. Seedling growth in vitro was also analysed. Finally, a mapping of different elements within the poplar seed was obtained by particle-induced X-ray emission (PIXE). Germination was similar between different progenies, refuting our hypothesis that seeds from a contaminated origin would have reduced germination capacity compared to those from a non-contaminated site. Seedling growth was not affected by the contaminated origin. Cadmium and Zn concentrations in fruits produced by P. alba trees in the contaminated sites were higher than by those from the non-contaminated site. However, the nutritional status of the trees was adequate in both cases. Cd in seedlings was higher in those from contaminated soils although lower than in fruits, indicating a certain exclusion from seeds. Preliminary results of the PIXE technique showed that Al and Zn were distributed uniformly in the seeds (Cd was not detected with this technique), while the nutrients P and S were concentrated in the cotyledons.

  20. In Situ Growth of In2S3 Nanorods in Poly(3-Hexylthiophene) Hybrid Films

    Science.gov (United States)

    Cota-Leal, M.; Sotelo-Lerma, M.; Corona-Corona, I.; Quevedo-Lopez, M. A.

    2016-04-01

    A novel and efficient gas-liquid method for the in situ synthesis of In2S3 nanorods in a poly(3-hexylthiophene) (P3HT) matrix is demonstrated. The method involves a self-contained reaction between Na2S and HCl that produces H2S, which reacts with a P3HT/InCl3 solution resulting in hybrid P3HT/In2S3 films. The Na2S solution is regenerated for further use. The method yielded results in In2S3 nanoparticles and nanorods in a P3HT matrix, as observed by transmission electron microscopy. The In2S3 nanorods are 3 nm wide and ~30 nm long. The size of the nanorods is dependent on the P3HT concentration. The band gap (E g) of the resulting In2S3/P3HT is in the range of 2.97-3.71 eV, as measured by UV-visible spectroscopy (UV-Vis) Charge transfer in the In2S3/P3HT was demonstrated by the presence of quenching in the fluorescence spectra of the composite. Chemical composition was investigated by energy dispersive x-ray spectroscopy analysis, as well as x-ray photoelectron spectroscopy. Both techniques demonstrated the formation of In2S3.

  1. Nitrogen and phosphorus management strategy for better growth and yield of sunflower (Helianthus annuus L. hybrid

    Directory of Open Access Journals (Sweden)

    Amjed Ali and Ijaz Rasool Noorka

    2013-05-01

    Full Text Available This study conducted during autumn season, 2010 investigated the effect of nitrogen and phosphorus on sunflower hybrid Hysun-33. The experiment was planned in randomized complete block design (factorial arrangement, with three replication, having net plot size of 3 x 7 m. The experiment comprised of 9 treatments, three levels of nitrogen and phosphorus, viz., 85, 135, 185 kg N ha-1, and 50, 75, 85 kg P ha-1. Nitrogen affected all estimated characters significantly, except plant population, while, phosphorus did not show significant effect on plant population and plant height. All other parameters, as leaf area plant-1, head diameter, 1000- achene weight and achene yield were affected significantly by different nitrogen and phosphorus levels. Interactive effects of nitrogen and phosphorus were significant in all these cases. The highest achene’s yield (2584 kg ha-1 was obtained with the application of 135-75 kg NP ha-1as against the lowest (1491kg ha-1 at 85-50 kg NP ha-1.

  2. Controlled release of human growth hormone fused with a human hybrid Fc fragment through a nanoporous polymer membrane

    Science.gov (United States)

    Kim, Eung-Sam; Jang, Do Soo; Yang, Seung Yun; Lee, Mi Nam; Jin, Kyeong Sik; Cha, Hyung Jin; Kim, Jin Kon; Sung, Young Chul; Choi, Kwan Yong

    2013-05-01

    Nanotechnology has been applied to the development of more effective and compatible drug delivery systems for therapeutic proteins. Human growth hormone (hGH) was fused with a hybrid Fc fragment containing partial Fc domains of human IgD and IgG4 to produce a long-acting fusion protein. The fusion protein, hGH-hyFc, resulted in the increase of the hydrodynamic diameter (ca. 11 nm) compared with the diameter (ca. 5 nm) of the recombinant hGH. A diblock copolymer membrane with nanopores (average diameter of 14.3 nm) exhibited a constant release rate of hGH-hyFc. The hGH-hyFc protein released in a controlled manner for one month was found to trigger the phosphorylation of Janus kinase 2 (JAK2) in human B lymphocyte and to exhibit an almost identical circular dichroism spectrum to that of the original hGH-hyFc, suggesting that the released fusion protein should maintain the functional and structural integrity of hGH. Thus, the nanoporous release device could be a potential delivery system for the long-term controlled release of therapeutic proteins fused with the hybrid Fc fragment.Nanotechnology has been applied to the development of more effective and compatible drug delivery systems for therapeutic proteins. Human growth hormone (hGH) was fused with a hybrid Fc fragment containing partial Fc domains of human IgD and IgG4 to produce a long-acting fusion protein. The fusion protein, hGH-hyFc, resulted in the increase of the hydrodynamic diameter (ca. 11 nm) compared with the diameter (ca. 5 nm) of the recombinant hGH. A diblock copolymer membrane with nanopores (average diameter of 14.3 nm) exhibited a constant release rate of hGH-hyFc. The hGH-hyFc protein released in a controlled manner for one month was found to trigger the phosphorylation of Janus kinase 2 (JAK2) in human B lymphocyte and to exhibit an almost identical circular dichroism spectrum to that of the original hGH-hyFc, suggesting that the released fusion protein should maintain the functional and

  3. Biomass production and carbon sequestration of a short-rotation forest with different poplar clones in northwest China.

    Science.gov (United States)

    Meifang, Yan; Lu, Wang; Honghui, Ren; Xinshi, Zhang

    2017-05-15

    Short Rotation Forestry (SRF) is of interest as producers of biomass for bio-energy, but also as carbon (C) sinks to mitigate CO2 emission. To investigate biomass production and C sequestration of SRF, ecosystem C stock (including C stored in tree biomass, litter and soil), NPP (net primary productivity), heterotrophic respiration (Rh) and NEP (net ecosystem productivity) of three poplar clone plantations were estimated by repeated field sampling in northwest China. Ecosystem C stock (105.62MgCha(-1)) was significantly lower in PB (P. balsamifera) stand than in PD (P. deltoids) and PE (P.×euramericana) stands (Pplantations all acted as C sinks, averagely absorbing 3.45MgCha(-1) during a year. Our results suggest that clone type is a main factor influencing C sequestration capacity of a plantation, along with determining the amount of biomass yield. The success of poplar plantations as a bio-energy resource largely depends on the selection of hybrid varieties. Copyright © 2017. Published by Elsevier B.V.

  4. Facing the Future: Effects of Short-Term Climate Extremes on Isoprene-Emitting and Nonemitting Poplar1

    Science.gov (United States)

    Vanzo, Elisa; Jud, Werner; Li, Ziru; Albert, Andreas; Domagalska, Malgorzata A.; Ghirardo, Andrea; Niederbacher, Bishu; Frenzel, Juliane; Beemster, Gerrit T.S.; Asard, Han; Rennenberg, Heinz; Sharkey, Thomas D.; Hansel, Armin; Schnitzler, Jörg-Peter

    2015-01-01

    Isoprene emissions from poplar (Populus spp.) plantations can influence atmospheric chemistry and regional climate. These emissions respond strongly to temperature, [CO2], and drought, but the superimposed effect of these three climate change factors are, for the most part, unknown. Performing predicted climate change scenario simulations (periodic and chronic heat and drought spells [HDSs] applied under elevated [CO2]), we analyzed volatile organic compound emissions, photosynthetic performance, leaf growth, and overall carbon (C) gain of poplar genotypes emitting (IE) and nonemitting (NE) isoprene. We aimed (1) to evaluate the proposed beneficial effect of isoprene emission on plant stress mitigation and recovery capacity and (2) to estimate the cumulative net C gain under the projected future climate. During HDSs, the chloroplastidic electron transport rate of NE plants became impaired, while IE plants maintained high values similar to unstressed controls. During recovery from HDS episodes, IE plants reached higher daily net CO2 assimilation rates compared with NE genotypes. Irrespective of the genotype, plants undergoing chronic HDSs showed the lowest cumulative C gain. Under control conditions simulating ambient [CO2], the C gain was lower in the IE plants than in the NE plants. In summary, the data on the overall C gain and plant growth suggest that the beneficial function of isoprene emission in poplar might be of minor importance to mitigate predicted short-term climate extremes under elevated [CO2]. Moreover, we demonstrate that an analysis of the canopy-scale dynamics of isoprene emission and photosynthetic performance under multiple stresses is essential to understand the overall performance under proposed future conditions. PMID:26162427

  5. Facing the Future: Effects of Short-Term Climate Extremes on Isoprene-Emitting and Nonemitting Poplar.

    Science.gov (United States)

    Vanzo, Elisa; Jud, Werner; Li, Ziru; Albert, Andreas; Domagalska, Malgorzata A; Ghirardo, Andrea; Niederbacher, Bishu; Frenzel, Juliane; Beemster, Gerrit T S; Asard, Han; Rennenberg, Heinz; Sharkey, Thomas D; Hansel, Armin; Schnitzler, Jörg-Peter

    2015-09-01

    Isoprene emissions from poplar (Populus spp.) plantations can influence atmospheric chemistry and regional climate. These emissions respond strongly to temperature, [CO2], and drought, but the superimposed effect of these three climate change factors are, for the most part, unknown. Performing predicted climate change scenario simulations (periodic and chronic heat and drought spells [HDSs] applied under elevated [CO2]), we analyzed volatile organic compound emissions, photosynthetic performance, leaf growth, and overall carbon (C) gain of poplar genotypes emitting (IE) and nonemitting (NE) isoprene. We aimed (1) to evaluate the proposed beneficial effect of isoprene emission on plant stress mitigation and recovery capacity and (2) to estimate the cumulative net C gain under the projected future climate. During HDSs, the chloroplastidic electron transport rate of NE plants became impaired, while IE plants maintained high values similar to unstressed controls. During recovery from HDS episodes, IE plants reached higher daily net CO2 assimilation rates compared with NE genotypes. Irrespective of the genotype, plants undergoing chronic HDSs showed the lowest cumulative C gain. Under control conditions simulating ambient [CO2], the C gain was lower in the IE plants than in the NE plants. In summary, the data on the overall C gain and plant growth suggest that the beneficial function of isoprene emission in poplar might be of minor importance to mitigate predicted short-term climate extremes under elevated [CO2]. Moreover, we demonstrate that an analysis of the canopy-scale dynamics of isoprene emission and photosynthetic performance under multiple stresses is essential to understand the overall performance under proposed future conditions.

  6. Leptin stimulates hepatic growth hormone receptor and insulin-like growth factor gene expression in a teleost fish, the hybrid striped bass.

    Science.gov (United States)

    Won, Eugene T; Douros, Jonathan D; Hurt, David A; Borski, Russell J

    2016-04-01

    Leptin is an anorexigenic peptide hormone that circulates as an indicator of adiposity in mammals, and functions to maintain energy homeostasis by balancing feeding and energy expenditure. In fish, leptin tends to be predominantly expressed in the liver, another important energy storing tissue, rather than in fat depots as it is in mammals. The liver also produces the majority of circulating insulin-like growth factors (IGFs), which comprise the mitogenic component of the growth hormone (GH)-IGF endocrine growth axis. Based on similar regulatory patterns of leptin and IGFs that we have documented in previous studies on hybrid striped bass (HSB: Morone saxatilis×Morone chrysops), and considering the co-localization of these peptides in the liver, we hypothesized that leptin might regulate the endocrine growth axis in a manner that helps coordinate somatic growth with energy availability. Using a HSB hepatocyte culture system to simulate autocrine or paracrine exposure that might occur within the liver, this study examines the potential for leptin to modulate metabolism and growth through regulation of IGF gene expression directly, or indirectly through the regulation of GH receptors (GHR), which mediate GH-induced IGF expression. First, we verified that GH (50nM) has a classical stimulatory effect on IGF-1 and additionally show it stimulates IGF-2 transcription in hepatocytes. Leptin (5 and/or 50nM) directly stimulated in vitro GHR2 gene expression within 8h of exposure, and both GHR1 and GHR2 as well as IGF-1 and IGF-2 gene expression after 24h. Cells were then co-incubated with submaximal concentrations of leptin and GH (25nM each) to test if they had a synergistic effect on IGF gene expression, possibly through increased GH sensitivity following GHR upregulation by leptin. In combination, however, the treatments only had an additive effect on stimulating IGF-1 mRNA despite their capacity to increase GHR mRNA abundance. This suggests that leptin's stimulatory

  7. Effects of drought stress on the growth, photosynthetic characteristics, and active oxygen metabolism of poplar seedlings%干旱胁迫对杨树幼苗生长、光合特性及活性氧代谢的影响

    Institute of Scientific and Technical Information of China (English)

    井大炜; 邢尚军; 杜振宇; 刘方春

    2013-01-01

    A pot experiment was conducted to study the effects of different water treatments (normal irrigation,light drought,moderate drought,and severe drought) on the growth,gas exchange,chlorophyll fluorescence characteristics,and active oxygen metabolism of poplar (Populus × euramericana cv.' Neva') seedlings in the experimental nursery of Shandong Forestry Academy from April to October,2011.As compared with those under normal irrigation,the growth of the seedling' s basal diameter under light,moderate,and severe drought stress decreased by 12.8%,44.5%,and 65.6%,and the height growth decreased by 12.2%,43.1%,and 57.2%,respectively.With the increasing extent and duration of drought stress,the maximal photochemical efficiency of PS Ⅱ,quantum yield,photochemical quenching coefficient,net photosynthetic rate,and stomatal conductance of the seedling leaves decreased gradually under light drought stress,while decreased rapidly under both moderate and severe drought stress.The non-photochemical quenching coefficient increased significantly under light drought stress,but decreased after an initial increase under moderate and severe drought.The leaf superoxide dismutase (SOD),peroxidase (POD),and catalase (CAT) activities under drought stress decreased after an initial increase,but definite differences existed in the responses of the three enzymes to drought stress and reactive oxygen.The leaf relative electric conductivity and malondialdehyde (MDA) content under drought stress increased significantly,plasma membrane was damaged,and massive ions leaked out.The most serious damage of plasma membrane was found under severe stress.Under light drought stress,the seedlings had higher photosynthetic efficiency and stronger oxidative enzyme defense system; under moderate and severe drought stress,the photosynthetic efficiency decreased significantly,and the oxidative enzyme defense system was damaged remarkably.%2011年4-10月在山东省林业科学研究

  8. Smart designing of new hybrid materials based on brushite-alginate and monetite-alginate microspheres: bio-inspired for sequential nucleation and growth.

    Science.gov (United States)

    Amer, Walid; Abdelouahdi, Karima; Ramananarivo, Hugo Ronald; Fihri, Aziz; El Achaby, Mounir; Zahouily, Mohamed; Barakat, Abdellatif; Djessas, Kamal; Clark, James; Solhy, Abderrahim

    2014-02-01

    In this report new hybrid materials based on brushite-alginate and monetite-alginate were prepared by self-assembling alginate chains and phosphate source ions via a gelation process with calcium ions. The alginate served as nanoreactor for nucleation and growth of brushite or/and monetite due to its gelling and swelling properties. The alginate gel framework, the crystalline phase and morphology of formed hybrid biomaterials were shown to be strongly dependent upon the concentration of the phosphate precursors. These materials were characterized by thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDX).

  9. Heat transfer mechanisms in poplar wood undergoing torrefaction

    Science.gov (United States)

    Sule, Idris O.; Mahmud, Shohel; Dutta, Animesh; Tasnim, Syeda Humaira

    2016-03-01

    Torrefaction, a thermal treatment process of biomass, has been proved to improve biomass combustible properties. Torrefaction is defined as a thermochemical process in reduced oxygen condition and at temperature range from 200 to 300 °C for shorter residence time whereby energy yield is maximized, can be a bridging technology that can lead the conventional system (e.g. coal-fired plants) towards a sustainable energy system. In efforts to develop a commercial operable torrefaction reactor, the present study examines the minimum input condition at which biomass is torrefied and explores the heat transfer mechanisms during torrefaction in poplar wood samples. The heat transfer through the wood sample is numerically modeled and analyzed. Each poplar wood is torrefied at temperature of 250, 270, and 300 °C. The experimental study shows that the 270 °C-treatment can be deduced as the optimal input condition for torrefaction of poplar wood. A good understanding of heat transfer mechanisms can facilitate the upscaling and downscaling of torrefaction process equipment to fit the feedstock input criteria and can help to develop treatment input specifications that can maximize process efficiency.

  10. Barcoding poplars (Populus L. from western China.

    Directory of Open Access Journals (Sweden)

    Jianju Feng

    Full Text Available BACKGROUND: Populus is an ecologically and economically important genus of trees, but distinguishing between wild species is relatively difficult due to extensive interspecific hybridization and introgression, and the high level of intraspecific morphological variation. The DNA barcoding approach is a potential solution to this problem. METHODOLOGY/PRINCIPAL FINDINGS: Here, we tested the discrimination power of five chloroplast barcodes and one nuclear barcode (ITS among 95 trees that represent 21 Populus species from western China. Among all single barcode candidates, the discrimination power is highest for the nuclear ITS, progressively lower for chloroplast barcodes matK (M, trnG-psbK (G and psbK-psbI (P, and trnH-psbA (H and rbcL (R; the discrimination efficiency of the nuclear ITS (I is also higher than any two-, three-, or even the five-locus combination of chloroplast barcodes. Among the five combinations of a single chloroplast barcode plus the nuclear ITS, H+I and P+I differentiated the highest and lowest portion of species, respectively. The highest discrimination rate for the barcodes or barcode combinations examined here is 55.0% (H+I, and usually discrimination failures occurred among species from sympatric or parapatric areas. CONCLUSIONS/SIGNIFICANCE: In this case study, we showed that when discriminating Populus species from western China, the nuclear ITS region represents a more promising barcode than any maternally inherited chloroplast region or combination of chloroplast regions. Meanwhile, combining the ITS region with chloroplast regions may improve the barcoding success rate and assist in detecting recent interspecific hybridizations. Failure to discriminate among several groups of Populus species from sympatric or parapatric areas may have been the result of incomplete lineage sorting, frequent interspecific hybridizations and introgressions. We agree with a previous proposal for constructing a tiered barcoding system in

  11. GENOME ENABLED MODIFICATION OF POPLAR ROOT DEVELOPMENT FOR INCREASED CARBON SEQUESTRATION

    Energy Technology Data Exchange (ETDEWEB)

    Busov, Victor

    2013-03-05

    DR5 as a reporter system to study auxin response in Populus Plant Cell Reports 32:453-463 Auxin responsive promoter DR5 reporter system is functional in Populus to monitor auxin response in tissues including leaves, roots, and stems. We described the behavior of the DR5::GUS reporter system in stably transformed Populus plants. We found several similarities with Arabidopsis, including sensitivity to native and synthetic auxins, rapid induction after treatment in a variety of tissues, and maximal responses in root tissues. There were also several important differences from Arabidopsis, including slower time to maximum response and lower induction amplitude. Young leaves and stem sections below the apex showed much higher DR5 activity than did older leaves and stems undergoing secondary growth. DR5 activity was highest in cortex, suggesting high levels of auxin concentration and/or sensitivity in this tissue. Our study shows that the DR5 reporter system is a sensitive and facile system for monitoring auxin responses and distribution at cellular resolution in poplar. The Populus AINTEGUMENTA LIKE 1 homeotic transcription factor PtAIL1 controls the formation of adventitious root primordia. Plant Physiol. 160: 1996-2006 Adventitious rooting is an essential but sometimes rate-limiting step in the clonal multiplication of elite tree germplasm, because the ability to form roots declines rapidly with age in mature adult plant tissues. In spite of the importance of adventitious rooting, the mechanism behind this developmental process remains poorly understood. We have described the transcriptional profiles that are associated with the developmental stages of adventitious root formation in the model tree poplar (Populus trichocarpa). Transcriptome analyses indicate a highly specific temporal induction of the AINTEGUMENTA LIKE1 (PtAIL1) transcription factor of the AP2 family during adventitious root formation. Transgenic poplar samples that overexpressed PtAIL1 were able to

  12. VACCINATION OF HYBRID STRIPED BASS: GROWTH, IMMUNE REACTION AND GENE EXPRESSION

    Directory of Open Access Journals (Sweden)

    Mark Westerman

    2012-10-01

    Full Text Available Hybrid striped bass (42.6+4.9 g wet wt; 139.3+6.1 mm length, were randomly stocked into one of 6 tanks (n=6 tank-1 of a custom designed, recirculating life support system (RLSS. Water quality was as follows: DO2 (6.50.6 mg l-1, pH (7.70.5, TAN (0.06-1.31 mg l-1, nitrite (0.06-0.60 mg l-1 and nitrate (2.0-32.1 mg l-1, salinity 5 ppt, temperature 28±1 oC. A 12:12 photophase:scotophase was used, with a 30 min. dusk-dawn dimming of lights. Fish were fed at 4% body wt d-1 as two separate feedings (08.00 and 16.00 h. Dietary crude protein and lipid levels were 40% and 10% respectively. Tanks were randomly paired and fish either left untreated, vaccinated, or sham injected. The vaccine employed was an experimental formalin killed Streptococcus iniae oil-in-water adjuvanted bacterin. Fish were weighed and measured bimonthly for 8 wk with group weights being employed to adjust feeding rates. At trial termination, all animals were weighed and measured, and their condition factor (CF and feed conversion ratios (FCR calculated. Visceral somatic (VSI and hepatosomatic (HSI indices and intraperitoneal fat (IPF and muscle ratios (MR were also assessed. Blood was taken from anaesthetized fish and hematocrit recorded. Blood was allowed to clot overnight at 5 oC after which serum protein levels were recorded and lysozyme activity measured. Livers were prepared for microarray evaluation using standard techniques using a Danio rerio genechip to assess global changes in gene expression. No differences were observed with respect to final weights, lengths, CF, FCR, or HSI although differences (P < 0.001 were determined for VSI, which was higher in control animals. Packed cell volume and serum protein levels were similar across groups (P > 0.05. Time-course of changes in serum lysozyme activity described an initial reduction in lysozyme activity followed by a rebounding in activity which peaked 25 days post-treatments. Evaluation of lysozyme activity among time

  13. A method for describing the canopy architecture of coppice poplar with allometric relationships.

    Science.gov (United States)

    Casella, Eric; Sinoquet, Hervé

    2003-12-01

    A multi-scale biometric methodology for describing the architecture of fast-growing short-rotation woody crops is used to describe 2-year-old poplar clones during the second rotation. To allow for expressions of genetic variability observed within this species (i.e., growth potential, leaf morphology, coppice and canopy structure), the method has been applied to two clones: Ghoy (Gho) (Populus deltoides Bartr. ex Marsh. x Populus nigra L.) and Trichobel (Tri) (Populus trichocarpa Torr. & A. Gray x Populus trichocarpa). The method operates at the stool level and describes the plant as a collection of components (shoots and branches) described as a collection of metameric elements, themselves defined as a collection of elementary units (internode, petiole, leaf blade). Branching and connection between the plant units (i.e., plant topology) and their spatial location, orientation, size and shape (i.e., plant geometry) describe the plant architecture. The methodology has been used to describe the plant architecture of 15 selected stools per clone over a 5-month period. On individual stools, shoots have been selected from three classes (small, medium and large) spanning the diameter distribution range. Using a multi-scale approach, empirical allometric relationships were used to parameterize elementary units of the plant, topological relationships and geometry (e.g., distribution of shoot diameters on stool, shoot attributes from shoot diameter). The empirical functions form the basis of the 3-D Coppice Poplar Canopy Architecture model (3-D CPCA), which recreates the architecture and canopy structure of fast-growing coppice crops at the plot scale. Model outputs are assessed through visual and quantitative comparisons between actual photographs of the coppice canopy and simulated images. Overall, results indicate a good predictive ability of the 3-D CPCA model.

  14. Overexpression of TaLEA gene from Tamarix androssowii improves salt and drought tolerance in transgenic poplar (Populus simonii × P. nigra.

    Directory of Open Access Journals (Sweden)

    Weidong Gao

    Full Text Available Late embryogenesis abundant (LEA genes were confirmed to confer resistance to drought and water deficiency. An LEA gene from Tamarixandrossowii (named TaLEA was transformed into Xiaohei poplar (Populussimonii × P. nigra via Agrobacterium. Twenty-five independent transgenic lines were obtained that were resistant to kanamycin, and 11 transgenic lines were randomly selected for further analysis. The polymerase chain reaction (PCR and ribonucleic acid (RNA gel blot indicated that the TaLEA gene had been integrated into the poplar genome. The height growth rate, malondialdehyde (MDA content, relative electrolyte leakage and damages due to salt or drought to transgenic and non-transgenic plants were compared under salt and drought stress conditions. The results showed that the constitutive expression of the TaLEA gene in transgenic poplars could induce an increase in height growth rate and a decrease in number and severity of wilted leaves under the salt and drought stresses. The MDA content and relative electrolyte leakage in transgenic lines under salt and drought stresses were significantly lower compared to those in non-transgenic plants, indicating that the TaLEA gene may enhance salt and drought tolerance by protecting cell membranes from damage. Moreover, amongst the lines analyzed for stress tolerance, the transgenic line 11 (T11 showed the highest tolerance levels under both salinity and drought stress conditions. These results indicated that the TaLEA gene could be a salt and drought tolerance candidate gene and could confer a broad spectrum of tolerance under abiotic stresses in poplars.

  15. Contribution factor of wood properties of three poplar clones to strength of laminated veneer lumber

    Science.gov (United States)

    Fucheng Bao; Feng Fu; Elvin Choong; Chung-Yun Hse

    2001-01-01

    The term "Contribution Factor" (c.) was introduced in this paper to indicate the contribution ratio of solid wood properties to laminated veneer lumber (LVL) strength. Three poplar (Populus sp.) clones were studied, and the results showed that poplar with good solid wood properties has high Contribution Factor. The average Contribution...

  16. WUS and STM-based reporter genes for studying meristem development in poplar

    Science.gov (United States)

    We describe the development of a reporter system for monitoring meristem initiation in poplar using promoters of poplar homologs to the meristem-active regulatory genes WUSCHEL (WUS) and SHOOTMERISTEMLESS (STM). When ~3 kb of the 5’ flanking regions of close homologs were used to drive expression o...

  17. Forage growth, yield and quality responses of Napier hybrid grass cultivars to three cutting intervals in the Himalayan foothills

    Directory of Open Access Journals (Sweden)

    Kesang Wangchuk

    2015-09-01

    Full Text Available A 3 x 3 factorial study was conducted in the southern foothills of Bhutan to compare 3 cultivars of Napier hybrid grass (Pennisetum purpureum x P. glaucum: Pakchong-1, CO-3 and Giant Napier, at 3 cutting intervals (40, 60 and 80 days, in terms of forage growth, dry matter (DM yield and crude protein (CP concentration. The effects of cultivar x cutting interval were significant only on tiller number per plant and leaf:stem ratio (LSR. CO-3 consistently produced the highest tiller number per plant, leaves per plant and LSR, while Pakchong-1 produced the lowest. Pakchong-1 plants were taller, had bigger tillers and basal circumference and higher stem DM production than CO-3 and Giant. Leaf CP for all cultivars was about 17%, while stem CP concentration was lower for Pakchong-1 than for the other cultivars (3.6 vs. 5.3%, P<0.05. While 40-day cutting intervals produced high quality forage, yields suffered marked-ly and the best compromise between yield and quality of forage seemed to occur with 60-day cutting intervals. Pakchong-1 seems to have no marked advantages over CO-3 and Giant for livestock feed, and feeding studies would verify this. Its higher stem DM yields may be advantageous for biogas production and this aspect should be investigated.Keywords: Bhutan, CO-3, crude protein , dry matter, Giant Napier, Pakchong-1.DOI: 10.17138/TGFT(3142-150

  18. A hybrid stochastic-deterministic computational model accurately describes spatial dynamics and virus diffusion in HIV-1 growth competition assay.

    Science.gov (United States)

    Immonen, Taina; Gibson, Richard; Leitner, Thomas; Miller, Melanie A; Arts, Eric J; Somersalo, Erkki; Calvetti, Daniela

    2012-11-01

    We present a new hybrid stochastic-deterministic, spatially distributed computational model to simulate growth competition assays on a relatively immobile monolayer of peripheral blood mononuclear cells (PBMCs), commonly used for determining ex vivo fitness of human immunodeficiency virus type-1 (HIV-1). The novel features of our approach include incorporation of viral diffusion through a deterministic diffusion model while simulating cellular dynamics via a stochastic Markov chain model. The model accounts for multiple infections of target cells, CD4-downregulation, and the delay between the infection of a cell and the production of new virus particles. The minimum threshold level of infection induced by a virus inoculum is determined via a series of dilution experiments, and is used to determine the probability of infection of a susceptible cell as a function of local virus density. We illustrate how this model can be used for estimating the distribution of cells infected by either a single virus type or two competing viruses. Our model captures experimentally observed variation in the fitness difference between two virus strains, and suggests a way to minimize variation and dual infection in experiments.

  19. Forage growth, yield and quality responses of Napier hybrid grass cultivars to three cutting intervals in the Himalayan foothills

    Directory of Open Access Journals (Sweden)

    Kesang Wangchuk

    2015-09-01

    Full Text Available A 3 x 3 factorial study was conducted in the southern foothills of Bhutan to compare 3 cultivars of Napier hybrid grass (Pennisetum purpureum x P. glaucum: Pakchong-1, CO-3 and Giant Napier, at 3 cutting intervals (40, 60 and 80 days, in terms of forage growth, dry matter (DM yield and crude protein (CP concentration. The effects of cultivar x cutting interval were significant only on tiller number per plant and leaf:stem ratio (LSR. CO-3 consistently produced the highest tiller number per plant, leaves per plant and LSR, while Pakchong-1 produced the lowest. Pakchong-1 plants were taller, had bigger tillers and basal circumference and higher stem DM production than CO-3 and Giant. Leaf CP for all cultivars was about 17%, while stem CP concentration was lower for Pakchong-1 than for the other cultivars (3.6 vs. 5.3%, P<0.05. While 40-day cutting intervals produced high quality forage, yields suffered marked-ly and the best compromise between yield and quality of forage seemed to occur with 60-day cutting intervals. Pakchong-1 seems to have no marked advantages over CO-3 and Giant for livestock feed, and feeding studies would verify this. Its higher stem DM yields may be advantageous for biogas production and this aspect should be investigated.Keywords: Bhutan, CO-3, crude protein , dry matter, Giant Napier, Pakchong-1.DOI: 10.17138/TGFT(3142-150

  20. The Growth Condition Comparison of Seeding Period of 1 2 Poplar Varieties in North-east of Ulan Buh Desert%乌兰布和沙漠东北部12种杨树品种幼苗期生长状况对比

    Institute of Scientific and Technical Information of China (English)

    黄雅茹; 赵英铭; 高君亮; 马迎宾; 余新春; 张格; 张瑞; 孙非; 郝玉光

    2016-01-01

    About 12 Poplar varieties including Beikang and 08 series were introduced as research ob-jects,by means of investigating seeding period survival rate,preserving rate,diameter at breast height and new shoots,using the method of subordinate function to study 12 kinds of fast growing Poplar in see-ding stage in North-east of Ulan Buh Desert adaptability to carry on the comprehensive evaluation.The results showed that the survival rate of fast growing Poplar was between 84.12%and 100%.Sample 08-01,Sample 08-07,Beikang 16 -27 had higher survival rate,the preserving rate was between 68.42% and 100%.08 -07,Beikang16 -27,08 -01 had higher preserving rate.Diameter at breast height increment was in the range of 0.13~1.35cm,and 08-09,08-03,08-01 had higher diameter at breast height increment,new shoots increment was in the range of 19.39~103.88cm,and Beikang 16-27,Beikang 16-8,08-03 had higher new shoots increment.To order by subordinate function,08-01,Beikang 16-27 and 08-09 fast growing Poplar at seeding stage were better adapted to the North-east of Ulan Buh Desert,and can be used as fine species of afforestation of protection forest in this area.%以北抗、08等系列的12种引进速生杨品种为研究对象,调查幼苗期成活率、保存率、胸径、新梢长,运用隶属函数法对12种速生杨幼苗在乌兰布和沙漠东北部的适应性进行综合评价。结果表明:速生杨各品种成活率在84.12%~100%之间,其中成活率较高的为08-01,08-07和北抗16-27;保存率在68.42%~100%之间,较高的为08-07、北抗16-27和08-01;胸径生长量在0.13~1.35cm 范围内,较高的为08-09,08-03,08-01;新梢生长量在19.39~103.88cm范围内,较高的为北抗16-27、北抗16-8和08-03。通过隶属函数值进行排序,08-01、北抗16-27和08-09等3种速生杨品种幼苗期在乌兰布和沙漠东北部的生长适应性较好,可以作为该区防护林造林优良品种。

  1. Hybrid simulation of nanoparticle growth and transport in a pulsed RF CCP sustained in silane

    Science.gov (United States)

    Jia, Wen-Zhu; Song, Yuan-Hong; Wang, You-Nian

    2016-09-01

    A pulsed RF silane plasma is studied numerically by adopting a self-consistent one-dimensional fluid/MC model. The large anions (typically Si12H25- and Si12H24-) in the discharge are the main precursors in the pathways leading to particle formation in a nucleation process. In order to study detailed growth of nanoparticles, an aerosol general dynamics equation is introduced and self-consistently coupled to the plasma fluid model, in which spatial distribution of nanoparticles, from several to tens of nm in diameter, is investigated. The numerical results show that, the ion drag force on smaller nanoparticles could to some extent exceed the electrostatic force in the plasma bulk, making the nanoparticles generally move towards the plasma boundaries. So the axial spatial distribution of nanoparticles is like a bimodal structure. With increase of the particle size, the distance between two peaks gradually becomes larger, reflecting the appearance of void in the plasma. At the same time, the presence of nanoparticles can lead to a decline of the electron density and a rise of the potential. In addition, by pulsing the RF source, size-controlled nanoparticles are expected to be extracted from the bulk plasma during the afterglow period. This work was supported by the National Natural Science Foundation of China (Grant No. 11275038).

  2. FEM growth and yield data monocultures - Sycamore

    NARCIS (Netherlands)

    Oldenburger, J.F.; Jansen, J.J.; Oosterbaan, A.; Mohren, G.M.J.; Ouden, den J.

    2016-01-01

    The current database is part of the FEM growth and yield database, a collection of growth and yield data from even-aged monocultures (douglas fir, common oak, poplar, Japanese Larch, Norway spruce, Scots pine, Corsican pine, Austrian pine, red oak and several other species, with only a few plots, ev

  3. Timing of photoperiodic competency causes phenological mismatch in balsam poplar (Populus balsamifera L.).

    Science.gov (United States)

    Soolanayakanahally, Raju Y; Guy, Robert D; Silim, Salim N; Song, Minghua

    2013-01-01

    Plant phenology is expected to be sensitive to climate warming. In boreal trees, spring flush is primarily temperature driven, whereas height growth cessation and autumn leaf senescence are predominantly controlled by photoperiod. Cuttings of 525 genotypes from the full range of balsam poplar were planted into two common gardens (Vancouver and Indian Head, Canada) at similar latitudes, but with differing winter temperatures and growing seasons. There was clinal variation in spring and, particularly, summer and fall phenology. Bud flush and, despite milder climate, bud set and leaf drop were earlier at Vancouver than at Indian Head by 44, 28 and 7 d, respectively. Although newly flushed growth is insensitive to photoperiod, many genotypes at both sites became competent before the summer solstice. At Vancouver, high-latitude genotypes set dormant terminal buds in mid-spring. Most other genotypes grew until midsummer or set bud temporarily and then experienced a second flush. In both gardens and in a growth chamber experiment, earlier bud set was associated with reduced height growth and higher root/shoot ratios. Shoots attained competency ~5 weeks after flushing, which would normally prevent dormancy induction before the solstice, but may be insufficient if spring advances by more than a few weeks.

  4. Genetic variation of the bud and leaf phenology of seventeen poplar clones in a short rotation coppice culture.

    Science.gov (United States)

    Pellis, A; Laureysens, I; Ceulemans, R

    2004-01-01

    Leaf phenology of 17 poplar ( Populus spp.) clones, encompassing spring phenology, length of growth period and end-of-year phenology, was examined over several years of different rotations. The 17 poplar clones differed in their latitude of origin (45 degrees 30'N to 51 degrees N) and were studied on a short rotation experimental field plantation, situated in Boom (province of Antwerpen, Belgium; 51 degrees 05'N, 04 degrees 22'E). A similar, clear pattern of bud burst was observed during the different years of study for all clones. Clones Columbia River, Fritzi Pauley, Trichobel (Populus trichocarpa) and Balsam Spire (Populus trichocarpa x Populus balsamifera) from 45 degrees 30'N to 49 degrees N reached bud burst (expressed as day of the year or degree day sums) almost every year earlier than clones Wolterson (Populus nigra), Gaver, Gibecq and Primo (Populus deltoides x Populus nigra) (50 degrees N to 51 degrees N). This observation could not be generalised to end-of-season phenology, for which a yearly returning pattern for all clones was lacking. Late bud burst and early leaf fall of some clones (Beaupré, Boelare, IBW1, IBW2, IBW3) was brought about by increasing rust incidence during the years of observation. For these clones, the variability in leaf phenology was reflected in high coefficients of variation among years. The patterns of genetic variation in leaf phenology have implications for short rotation intensive culture forestry and management of natural populations. Moreover, the variation in phenology reported here is relevant with regard to the genetic mapping of poplar.

  5. Effect of epiphytes on the extent of necrotic injuries of resistant and susceptible poplar clones infected with Dothichiza populea.

    Science.gov (United States)

    Weyman-Kaczmarkowa, W; Pedziwilk, Z

    2001-01-01

    Poplar cuttings of a resistant clone, Populus 'Grandis', and susceptible clones, Populus nigra 'Italica' and Populus 'Robusta', were infected with the pathogenic fungus Dothichiza populea alone, or with the pathogen and one of five strains of epiphytes antagonistic towards it (in vitro), isolated from poplar bark. The extent of injury was examined for 28 days after infection by determining the length of necrotic patches and their area as expressed in per cent of the total area of a cutting or the area of necrotic injuries caused by the pathogen alone. All the poplar cuttings of both the resistant and susceptible clones became diseased when infected with the pathogen alone. Surprisingly enough, however, the least affected clone was the susceptible P. 'Robusta', in which necrotic injuries covered 28% of the total area, as against 40% and 70% in the resistant P. 'Grandis' and the susceptible P. nigra 'Italica', respectively. When the cuttings were infected simultaneously with Dothichiza populea and its antagonistic epiphytes, the diseased area in the resistant clone diminished by as much as two-thirds, and in the susceptible P nigra 'Italica', by one-third in comparison with the area affected by the pathogen alone. In turn, in the susceptible P. 'Robusta' the introduction of three out of five epiphytes stimulated the growth of the pathogenic fungus producing on average a double increase in the necrotic area. The differences in the response of the pathogen to the presence of epiphytes recorded in the susceptible clones indicate a marked influence of the plant on the nature of interactions between its epiphytic microflora and the pathogen.

  6. Biological nitrogen fixation and biomass accumulation within poplar clones as a result of inoculations with diazotrophic endophyte consortia.

    Science.gov (United States)

    Knoth, Jenny L; Kim, Soo-Hyung; Ettl, Gregory J; Doty, Sharon L

    2014-01-01

    Sustainable production of biomass for bioenergy relies on low-input crop production. Inoculation of bioenergy crops with plant growth-promoting endophytes has the potential to reduce fertilizer inputs through the enhancement of biological nitrogen fixation (BNF). Endophytes isolated from native poplar growing in nutrient-poor conditions were selected for a series of glasshouse and field trials designed to test the overall hypothesis that naturally occurring diazotrophic endophytes impart growth promotion of the host plants. Endophyte inoculations contributed to increased biomass over uninoculated control plants. This growth promotion was more pronounced with multi-strain consortia than with single-strain inocula. Biological nitrogen fixation was estimated through (15)N isotope dilution to be 65% nitrogen derived from air (Ndfa). Phenotypic plasticity in biomass allocation and branch production observed as a result of endophyte inoculations may be useful in bioenergy crop breeding and engineering programs.

  7. GROWTH PERFORMANCE AND FEED CONVERSION RATIO (FCR OF HYBRID FINGERLINGS (CATLA CATLA X LABEO ROHITA FED ON COTTONSEED MEAL, SUNFLOWER MEAL AND BONE MEAL

    Directory of Open Access Journals (Sweden)

    T. SAHZADI, M. SALIM, UM-E-KALSOOM AND K. SHAHZAD

    2006-10-01

    Full Text Available An experiment was conducted in six glass aquaria to study the growth performance and feed conversion ratio (FCR of hybrid fingerlings (Catla catla x Labeo rohita fed on sunflower meal, cottonseed meal and bone meal. Two replicates for each ingredient were followed. The feed was supplied at the rate of 4% of wet body weight of fingerlings twice a day. The hybrid (Catla catla x Labeo rohita fingerlings gained highest body weight (1.62 ± 0.0 g on sunflower meal, followed by cottonseed meal (1.61 ± 0.01 g and bone meal (1.52 ± 0.0 g. The total length obtained by hybrid fish was 6.35 ± 0.05 cm on sunflower meal, 6.12 ± 0.05 cm on cottonseed meal and 5.85 ± 0.05 cm on bone meal. The overall mean values of FCR were lower (better on sunflower meal (1.78 ± 0.05, followed by cottonseed meal (2.17 ± 0.01 and bone meal (2.46 ± 0.01. Thus, The sunflower meal and cottonseed meal, on the basis of growth performance and better FCR, can be included in the feed formulation for hybrid fingerlings.

  8. Pulping performance of transgenic poplar with depressed Caffeoyl-CoA O-methyltransferase

    Institute of Scientific and Technical Information of China (English)

    WEI JianHua; WANG YanZhen; WANG HongZhi; LI RuiFen; LIN Nan; MA RongCai; QU LeQing; SONG YanRu

    2008-01-01

    This paper evaluated pulping performance of 3-year-old field-grown transgenic poplar (Populus tremula × Populus alba). The transgenic poplar with anti-sense CCoAOMT had an about 13% decreased lignin content, in which a slight increment was found in S/G ratio. Chemical analysis showed that the trans-genic poplar had significantly less benezene-ethanol extractive than that of control wood, but no sig-nificant differences were found in contents of ash, cold water extractive, hot water extractive, 1% NaOH extractive, holocellulose, pentosans and cellulose. Fiber assay demonstrated that down-regulation of CCoAOMTexpression improved the fiber quality in transgenic poplar. Kraft pulping showed that lower lignin in transgenic poplar led to remarkable improved pulp quality and increased pulp yield.

  9. Effects of climate factors on the height increment of poplar protection forest in the riverbank field

    Institute of Scientific and Technical Information of China (English)

    LIHai-mei; HEXing-yuan; WANGKui-ling

    2004-01-01

    Based on the data of stand investigation and stem analysis, the effects of climate factors on the poplar protection forest increment in the riverbank field of the Dalinghe and Xiaolinghe rivers of Liaoning Province, China were studied by stepwise regression procedure and grey system theories and methods. A regression model reflecting the correlation between the height increment of poplar protection forest and climatic factors was developed. The order of grey relevance for the effect of climatic factors on the height increment of poplar protection forest is" light>water>heat, and it could be interpreted that the poplar increment was mainly influenced by light factor, water factor, and heat factor. This result will provide scientific basis for the intensive cultivation and regeneration of the poplar protection forest in riverbank field in similar regions in China.

  10. The use of the white poplar (Populus alba L.) biomass as fuel

    Institute of Scientific and Technical Information of China (English)

    Tatiana Griu; Aurel Lunguleasa

    2016-01-01

    We determined the calorific value of white poplar (Populus alba L.) woody biomass to use it as fire-wood. The value of 19.133 MJ kg-1 obtained experimen-tally shows that the white poplar can be quite successfully used as firewood. Being of a lower quality in comparison with usual beech firewood, the white poplar has similar calorific value. The white poplar has a calorific density of 30.7%lower than that of current firewood. That is why the price of this firewood from white poplar is lower accord-ingly. Also, the prognosis of calorific value on the basis of the main chemical elements, being very close to the experimental value (?2.6%), indicates an appropriate value can be achieved to be used for investigation with the chemical element analysis.

  11. Progress in the Study of Molecular Genetic Improvements of Poplar in China

    Institute of Scientific and Technical Information of China (English)

    Shan-Zhi Lin; Zhi-Yi Zhang; Qian Zhang; Yuan-Zhen Lin

    2006-01-01

    The poplar is one of the most economically important and intensively studied tree species owing to its wide application in the timber industry and as a model material for the study of woody plants. The natural resource of poplars in China is replete. Over the past 10 years, the application of molecular biological techniques to genetic improvements in poplar species has been widely studied in China. Recent advances in molecular genetic improvements of poplar, including cDNA library construction, gene cloning and identification, genetic engineering, gene expression, genetic linkage map construction, mapping of quantitative trait loci (QTL) and molecular-assisted selection, are reviewed in the present paper. In addition, the application of modern biotechnology to molecular improvements in the genetic traits of the poplar and some unsolved problems are discussed.

  12. Smart designing of new hybrid materials based on brushite-alginate and monetite-alginate microspheres: Bio-inspired for sequential nucleation and growth

    Energy Technology Data Exchange (ETDEWEB)

    Amer, Walid [MAScIR Foundation, INANOTECH, Rabat Design, Rue Mohamed El Jazouli, Madinat El Irfane 10100 Rabat (Morocco); Abdelouahdi, Karima [Centre National pour la Recherche Scientifique et Technique (CNRST), Division UATRS, Angle Allal Fassi/FAR, B.P. 8027, Hay Riad, 10000 Rabat (Morocco); Ramananarivo, Hugo Ronald; Fihri, Aziz; El Achaby, Mounir [MAScIR Foundation, INANOTECH, Rabat Design, Rue Mohamed El Jazouli, Madinat El Irfane 10100 Rabat (Morocco); Zahouily, Mohamed [Laboratoire de Matériaux, Catalyse et Valorisation des Ressources Naturelles, URAC 24, Faculté des Sciences et Techniques, Université Hassan II, Mohammedia B.P. 146, 20650 (Morocco); Barakat, Abdellatif [SUPAGRO-INRA-CIRAD-UMR IATE 1208, Ingenierie des Agropolymères et Technologies Emergentes, 2, Place Pierre Viala-Bât 31, 34060 Montpellier cedex 1 (France); Djessas, Kamal [CNRS-PROMES Tecnosud, F-66100 Perpignan (France); Clark, James [Green Chemistry, Centre of Excellence, University of York, York YO10 5DD (United Kingdom); Solhy, Abderrahim, E-mail: a.solhy@mascir.com [MAScIR Foundation, INANOTECH, Rabat Design, Rue Mohamed El Jazouli, Madinat El Irfane 10100 Rabat (Morocco)

    2014-02-01

    In this report new hybrid materials based on brushite-alginate and monetite-alginate were prepared by self-assembling alginate chains and phosphate source ions via a gelation process with calcium ions. The alginate served as nanoreactor for nucleation and growth of brushite or/and monetite due to its gelling and swelling properties. The alginate gel framework, the crystalline phase and morphology of formed hybrid biomaterials were shown to be strongly dependent upon the concentration of the phosphate precursors. These materials were characterized by thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDX). - Graphical abstract: A new class of hybrid materials based on brushite{sub a}lginate and monetite{sub a}lginate were prepared for the first time by adopting a soft and clean route. Thanks to their gelling and swelling properties, alginate porous polysaccharide microspheres behave as nanoreactors for nucleating, growing and hosting of the phosphate cements such as brushite or monetite. - Highlights: • New structured hybrid materials are prepared from biopolymer and phosphates. • Evidence for a new route for the synthesis of hybrid materials alginate-brushite and alginate-monetite via ionotropic gel of alginate. • The concentration of phosphate has a role crucial for selectivity to monetite or brushite.

  13. Suppression subtractive hybridization profiles of radial growth phase and metastatic melanoma cell lines reveal novel potential targets

    Directory of Open Access Journals (Sweden)

    Espreafico Enilza M

    2008-01-01

    Full Text Available Abstract Background Melanoma progression occurs through three major stages: radial growth phase (RGP, confined to the epidermis; vertical growth phase (VGP, when the tumor has invaded into the dermis; and metastasis. In this work, we used suppression subtractive hybridization (SSH to investigate the molecular signature of melanoma progression, by comparing a group of metastatic cell lines with an RGP-like cell line showing characteristics of early neoplastic lesions including expression of the metastasis suppressor KISS1, lack of αvβ3-integrin and low levels of RHOC. Methods Two subtracted cDNA collections were obtained, one (RGP library by subtracting the RGP cell line (WM1552C cDNA from a cDNA pool from four metastatic cell lines (WM9, WM852, 1205Lu and WM1617, and the other (Met library by the reverse subtraction. Clones were sequenced and annotated, and expression validation was done by Northern blot and RT-PCR. Gene Ontology annotation and searches in large-scale melanoma expression studies were done for the genes identified. Results We identified 367 clones from the RGP library and 386 from the Met library, of which 351 and 368, respectively, match human mRNA sequences, representing 288 and 217 annotated genes. We confirmed the differential expression of all genes selected for validation. In the Met library, we found an enrichment of genes in the growth factors/receptor, adhesion and motility categories whereas in the RGP library, enriched categories were nucleotide biosynthesis, DNA packing/repair, and macromolecular/vesicular trafficking. Interestingly, 19% of the genes from the RGP library map to chromosome 1 against 4% of the ones from Met library. Conclusion This study identifies two populations of genes differentially expressed between melanoma cell lines from two tumor stages and suggests that these sets of genes represent profiles of less aggressive versus metastatic melanomas. A search for expression profiles of melanoma in

  14. Comparative Reproductive and Growth Performance of Clarias gariepinus (Burchell, 1822) and Its Hybrid Induced with Synthetic Hormone and Pituitary Gland of Clarias gariepinus

    OpenAIRE

    Ndimele, Prince Emeka; Owodeinde, Fatai Gbolahan

    2012-01-01

    A study was conducted to determine the comparative reproductive, growth performances and nutrient utilization of Clarias gariepinus and its hybrid "heteroclarias" using ovaprim and pituitary extract of male and female C. gariepinus. The experimental broodstocks consisted of 6 female C. gariepinus (2 each were induced separately with ovaprim, male pituitary of C. gariepinus and female pituitary of C. gariepinus), 3 male C. gariepinus and 3 male Heterobranchus bidorsalis. 2 female C. ...

  15. Resource allocation among sexual, clonal reproduction and vegetative growth of two Potamogeton species and their hybrid:Adaptability of the hybrid in relation to its parents

    Institute of Scientific and Technical Information of China (English)

    Fan LIU; Xiao-Lin ZHANG; Qing-Feng WANG; Hui LIU; Guang-Xi WANG; Wei LI

    2013-01-01

    Resource allocation,as well as the tradeoffs among different reproductive components,plays an important role in the adaptability of plants to different environments.The hybrid may exhibit a higher adaptability in life history in heterogeneous environments because of the genetic variation derived from its parents.In this study,we exploited three levels of water depths and two types of sediments to investigate the resource allocation pattern of the first generation of the natural hybrid Potamogeton × intortifolius compared to its parents P.wrightii and P.perfoliatus.We also measured the ramet survivorship and the seed set of the hybrid P.× intortifolius.Our results showed that P.×intortifolius had higher ramet survival than its parents at 1.5-m water depth on clay sediment.The possible tradeoffs showed that in P.×intortifolius the tradeoff pattern between sexual and clonal reproduction was more pronounced in limiting environments.The individuals allocated more resources to sexual reproduction when the environment was limiting,which might confer a higher ability to utilize resources,to produce offspring and to found new populations.Although the seed set of P.×intortifolius was lower than its parents,it had a higher ability to increase its seed set when the environment was limiting (sandy sediment) than its parents,which might benefit its future survival.These results indicated that the F1 hybrid P.×intortifolius was more able to adapt to limiting environments than one or both of its two parental taxa.

  16. Comparative transcriptomic analysis reveals the roles of overlapping heat-/drought-responsive genes in poplars exposed to high temperature and drought

    Science.gov (United States)

    Jia, Jingbo; Zhou, Jing; Shi, Wenguang; Cao, Xu; Luo, Jie; Polle, Andrea; Luo, Zhi-Bin

    2017-01-01

    High temperature (HT) and drought are both critical factors that constrain tree growth and survival under global climate change, but it is surprising that the transcriptomic reprogramming and physiological relays involved in the response to HT and/or drought remain unknown in woody plants. Thus, Populus simonii saplings were exposed to either ambient temperature or HT combined with sufficient watering or drought. RNA-sequencing analysis showed that a large number of genes were differentially expressed in poplar roots and leaves in response to HT and/or desiccation, but only a small number of these genes were identified as overlapping heat-/drought-responsive genes that are mainly involved in RNA regulation, transport, hormone metabolism, and stress. Furthermore, the overlapping heat-/drought-responsive genes were co-expressed and formed hierarchical genetic regulatory networks under each condition compared. HT-/drought-induced transcriptomic reprogramming is linked to physiological relays in poplar roots and leaves. For instance, HT- and/or drought-induced abscisic acid accumulation and decreases in auxin and other phytohormones corresponded well with the differential expression of a few genes involved in hormone metabolism. These results suggest that overlapping heat-/drought-responsive genes will play key roles in the transcriptional and physiological reconfiguration of poplars to HT and/or drought under future climatic scenarios. PMID:28233854

  17. Nursery inoculation with the arbuscular mycorrhizal fungus Glomus viscosum and its effect on the growth and physiology of hybrid artichoke seedlings

    Directory of Open Access Journals (Sweden)

    Angela Campanelli

    2011-07-01

    Full Text Available Most nurseries operating in Italy adopt high technologies and produce transplants that well suit and satisfy the grower’s need to produce high value crops. Mycorrhizas are discussed as a tool for improving and developing plant production in the nursery. Much research has been carried out on mycorrhizal symbiosis and we now know more about the symbiontic relationship between fungi and host plants. Plants receive numerous benefits from this symbiosis which are more macroscopic the earlier in the ontogenetic cycle this symbiosis is established. Therefore, it appears that the most effective period in which the inoculum should be made corresponds to the in-nursery growing stage. The earlier the plant is inoculated, the more evident the effect will be. In this study, several aspects related to the physiological foundations of arbuscular mycorrhiza in artichoke plants are presented. The main goal was to study the effects of mycorrhiza on the growth and physiological parameters of three hybrids of artichokes growing in the nursery. The experimental 3¥2 design included two treatments (with or without arbuscular mycorrhizal fungi and three hybrids of artichokes marketed by Nunhems (Opal F1, Madrigal F1, Concerto F1. Mycorrhizal plants have greater shoot length, leaf area, shoot and root fresh and dry mass, and root density. This also corresponded with increased photosynthetic rates and stomatal conductance of mycorrhizal plants. Mycorrhizal colonization improves relative water content and increases proline concentration in vegetal tissue. Inoculation produced the most beneficial effect on hybrid Madrigal F1 and on hybrid Opal F1; the best mycorrhizal affinity was enhanced when compared to hybrid Concerto F1. The results showed that mycorrhizal symbiosis stimulated the growth of inoculated seedlings providing a qualitatively good propagation material.

  18. Nursery inoculation with the arbuscular mycorrhizal fungus Glomus viscosum and its effect on the growth and physiology of hybrid artichoke seedlings

    Directory of Open Access Journals (Sweden)

    Angela Campanelli

    2011-09-01

    Full Text Available Most nurseries operating in Italy adopt high technologies and produce transplants that well suit and satisfy the grower’s need to produce high value crops. Mycorrhizas are discussed as a tool for improving and developing plant production in the nursery. Much research has been carried out on mycorrhizal symbiosis and we now know more about the symbiontic relationship between fungi and host plants. Plants receive numerous benefits from this symbiosis which are more macroscopic the earlier in the ontogenetic cycle this symbiosis is established. Therefore, it appears that the most effective period in which the inoculum should be made corresponds to the in-nursery growing stage. The earlier the plant is inoculated, the more evident the effect will be. In this study, several aspects related to the physiological foundations of arbuscular mycorrhiza in artichoke plants are presented. The main goal was to study the effects of mycorrhiza on the growth and physiological parameters of three hybrids of artichokes growing in the nursery. The experimental 3¥2 design included two treatments (with or without arbuscular mycorrhizal fungi and three hybrids of artichokes marketed by Nunhems (Opal F1, Madrigal F1, Concerto F1. Mycorrhizal plants have greater shoot length, leaf area, shoot and root fresh and dry mass, and root density. This also corresponded with increased photosynthetic rates and stomatal conductance of mycorrhizal plants. Mycorrhizal colonization improves relative water content and increases proline concentration in vegetal tissue. Inoculation produced the most beneficial effect on hybrid Madrigal F1 and on hybrid Opal F1; the best mycorrhizal affinity was enhanced when compared to hybrid Concerto F1. The results showed that mycorrhizal symbiosis stimulated the growth of inoculated seedlings providing a qualitatively good propagation material.

  19. Differential Gene Expression Between Hybrids and Their Parents During the Four Crucial Stages of Cotton Growth and Development

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yun-lei; YU Shu-xun; XING Chao-zhu; FAN Shu-li; SONG Mei-zhen; YE Wu-wei

    2009-01-01

    The study aims to clarify the differential gene expression between cotton hybrids and their parents in order to better understand the molecular basis of cotton heterosis. The research focused on cotton heterotic and lower heterotic hybrids and their parents during the four crucial stages, which were analyzed using a differential display technique. The results indicated that there were both quantitative and qualitative differences in gene expression amongst them. The quantitative differences include over- and under-expression of parental genes and the dominant expression of highly-expressed parental genes in hybrids. In contrast, the qualitative differences are the following: (i) Bands were observed in both parents but not in the F1 hybrid (BPnF1); (ii) bands occurred in either of the parents but not in the F1 hybrid (UPnF1); (iii) bands presented only in the F1 hybrid but not in either of the parents (UF1nP); and (iv) bands were detected in either of the parents and the F1 hybrid (UPF1). Overall, the major differences of gene expression occurred in the qualitative level and four related differential patterns were observed. Furthermore, the amount of differential patterns during the flowering stage was relatively higher than those of other stages. At this juncture, both the amount of hybrid-specific expression patterns at flowering stage and the silenced expression patterns at boll-forming stage in highly heterotic hybrids were found higher than those in the lower heterotic ones. It was concluded that significant differences of gene expression in leaves were present between cotton hybrid and its parents during the whole growing stages. Hence, these differences might be responsible for the observed cotton heterosis.

  20. GENOME ENABLED MODIFICATION OF POPLAR ROOT DEVELOPMENT FOR INCREASED CARBON SEQUESTRATION

    Energy Technology Data Exchange (ETDEWEB)

    Busov, Victor

    2013-03-05

    DR5 as a reporter system to study auxin response in Populus Plant Cell Reports 32:453-463 Auxin responsive promoter DR5 reporter system is functional in Populus to monitor auxin response in tissues including leaves, roots, and stems. We described the behavior of the DR5::GUS reporter system in stably transformed Populus plants. We found several similarities with Arabidopsis, including sensitivity to native and synthetic auxins, rapid induction after treatment in a variety of tissues, and maximal responses in root tissues. There were also several important differences from Arabidopsis, including slower time to maximum response and lower induction amplitude. Young leaves and stem sections below the apex showed much higher DR5 activity than did older leaves and stems undergoing secondary growth. DR5 activity was highest in cortex, suggesting high levels of auxin concentration and/or sensitivity in this tissue. Our study shows that the DR5 reporter system is a sensitive and facile system for monitoring auxin responses and distribution at cellular resolution in poplar. The Populus AINTEGUMENTA LIKE 1 homeotic transcription factor PtAIL1 controls the formation of adventitious root primordia. Plant Physiol. 160: 1996-2006 Adventitious rooting is an essential but sometimes rate-limiting step in the clonal multiplication of elite tree germplasm, because the ability to form roots declines rapidly with age in mature adult plant tissues. In spite of the importance of adventitious rooting, the mechanism behind this developmental process remains poorly understood. We have described the transcriptional profiles that are associated with the developmental stages of adventitious root formation in the model tree poplar (Populus trichocarpa). Transcriptome analyses indicate a highly specific temporal induction of the AINTEGUMENTA LIKE1 (PtAIL1) transcription factor of the AP2 family during adventitious root formation. Transgenic poplar samples that overexpressed PtAIL1 were able to

  1. 杨树人工林边缘效应的初步研究%Preliminary Study on Edge Effects for Poplar Plantation

    Institute of Scientific and Technical Information of China (English)

    吴生广

    2013-01-01

      The influences of edge effects within different directions on different places on growth of poplar in Liaoyang Region were studied .The result shows that :in three plots of 12-year-old Populus liaoningensis ,9-year-old Popu-lus × euramericana cv .N3930 ,8-year-old Populus × euramericana cv .N3930 ,depth of the edge in east direction are all maximum ;the edge effect is also shown by the largest ,followed by northern direction .In practice ,increas-ing the poplar trees in the eastern direction not only can increase the proportion of poplar in eastern edge of the woods in the entire forest ,but also can significantly improve biomass production & economic benefits of the poplar .%  通过辽阳地区不同杨树林地不同方向上的边缘效应对杨树生长影响的研究,结果表明:在12年生辽宁杨、9年生3930杨和8年生3930杨3个样地中,皆以东部方向上的边缘深度最大,表现出的边缘效应亦最大,北部方向次之。实践中,可通过增加东部方向上杨树的株数,使杨树林东部边缘部分在整个林子中的比例增大,可显著提高杨树的生物产量和经济效益。

  2. Genome-wide transcriptome profiling of black poplar (Populus nigra L.) under boron toxicity revealed candidate genes responsible in boron uptake, transport and detoxification.

    Science.gov (United States)

    Yıldırım, Kubilay; Uylaş, Senem

    2016-12-01

    Boron (B) is an essential nutrient for normal growth of plants. Despite its low abundance in soils, it could be highly toxic to plants in especially arid and semi-arid environments. Poplars are known to be tolerant species to B toxicity and accumulation. However, physiological and gene regulation responses of these trees to B toxicity have not been investigated yet. Here, B accumulation and tolerance level of black poplar clones were firstly tested in the current study. Rooted cutting of these clones were treated with elevated B toxicity to select the most B accumulator and tolerant genotype. Then we carried out a microarray based transcriptome experiment on the leaves and roots of this genotype to find out transcriptional networks, genes and molecular mechanisms behind B toxicity tolerance. The results of the study indicated that black poplar is quite suitable for phytoremediation of B pollution. It could resist 15 ppm soil B content and >1500 ppm B accumulation in leaves, which are highly toxic concentrations for almost all agricultural plants. Transcriptomics results of study revealed totally 1625 and 1419 altered probe sets under 15 ppm B toxicity in leaf and root tissues, respectively. The highest induction were recorded for the probes sets annotated to tyrosine aminotransferase, ATP binding cassette transporters, glutathione S transferases and metallochaperone proteins. Strong up regulation of these genes attributed to internal excretion of B into the cell vacuole and existence of B detoxification processes in black poplar. Many other candidate genes functional in signalling, gene regulation, antioxidation, B uptake and transport processes were also identified in this hyper B accumulator plant for the first time with the current study. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  3. Graphene/single-walled carbon nanotube hybrids: one-step catalytic growth and applications for high-rate Li-S batteries.

    Science.gov (United States)

    Zhao, Meng-Qiang; Liu, Xiao-Fei; Zhang, Qiang; Tian, Gui-Li; Huang, Jia-Qi; Zhu, Wancheng; Wei, Fei

    2012-12-21

    The theoretically proposed graphene/single-walled carbon nanotube (G/SWCNT) hybrids by placing SWCNTs among graphene planes through covalent C-C bonding are expected to have extraordinary physical properties and promising engineering applications. However, the G/CNT hybrids that have been fabricated differ greatly from the proposed G/SWCNT hybrids because either the covalent C-C bonding is not well constructed or only multiwalled CNTs/carbon nanofibers rather than SWCNTs are available in the hybrids. Herein, a novel G/SWCNT hybrid was successfully fabricated by a facile catalytic growth on layered double hydroxide (LDH) at a high temperature over 950 °C. The thermally stable Fe nanoparticles and the uniform structure of the calcined LDH flakes are essential for the simultaneously catalytic deposition of SWCNTs and graphene. The SWCNTs and the CVD-grown graphene, as well as the robust connection between the SWCNTs and graphene, facilitated the construction of a high electrical conductive pathway. The internal spaces between the two stacked graphene layers and among SWCNTs offer room for sulfur storage. Therefore, the as obtained G/SWCNT-S cathode exhibited excellent performance in Li-S batteries with a capacity as high as 650 mAh g(-1) after 100 cycles even at a high current rate of 5 C. Such a novel G/SWCNT hybrid can serve not only as a prototype to shed light on the chemical principle of G/CNT synthesis but also as a platform for their further applications in the area of nanocomposites, heterogeneous catalysis, drug delivery, electrochemical energy storage, and so on.

  4. Wood Properties of Poplar from Stand Affected by Acid Rain

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Wood properties from 28 trees (Populus euramericana) selected from healthy and acid rain damaged forest were measured to evaluate the possible impacts on wood quality and utilization. On the heavily damaged location, the pH value of precipitation ranged from 3.7-5.0, and sulfate loading ranged from 20-40 kg·ha-2.y-1. Quantitative and qualitative studies on ring width, physical properties and mechanical properties indicated that changes of wood properties between diseased and healthy poplar occurred. Aci...

  5. Greenhouse gas balance of cropland conversion to bioenergy poplar short rotation coppice

    Science.gov (United States)

    Sabbatini, S.; Arriga, N.; Bertolini, T.; Castaldi, S.; Chiti, T.; Consalvo, C.; Njakou Djomo, S.; Gioli, B.; Matteucci, G.; Papale, D.

    2015-05-01

    The production of bioenergy in Europe is one of the strategies conceived to reduce greenhouse gas (GHG) emissions. The suitability of the land use change from a cropland (REF site) to a short rotation coppice plantation of hybrid poplar (SRC site) was investigated by comparing the GHG budgets of these two systems over 24 months in Viterbo, Italy. Eddy covariance measurements were carried out to quantify the net ecosystem exchange of CO2 (FCO2), whereas chambers were used to measure N2O and CH4 emissions from soil. Soil organic carbon (SOC) of an older poplar plantation was used to estimate via a regression the SOC loss due to SRC establishment. Emissions from tractors and from production and transport of agricultural inputs (FMAN) were modelled and GHG emission offset due to fossil fuel substitution was credited to the SRC site considering the C intensity of natural gas. Emissions due to the use of the biomass (FEXP) were also considered. The suitability was finally assessed comparing the GHG budgets of the two sites. FCO2 was the higher flux in the SRC site (-3512 ± 224 g CO2 eq m-2 in two years), while in the REF site it was -1838 ± 107 g CO2 m-2 in two years. FEXP was equal to 1858 ± 240 g CO2 m-2 in 24 months in the REF site, thus basically compensating FCO2, while it was 1118 ± 521 g CO2 eq m-2 in 24 months in the SRC site. This latter could offset -379.7 ± 175.1 g CO2 eq m-2 from fossil fuel displacement. Soil CH4 and N2O fluxes were negligible. FMAN weighed 2 and 4% in the GHG budgets of SRC and REF sites respectively, while the SOC loss weighed 455 ± 524 g CO2 m-2 in two years. Overall, the REF site was close to neutrality in a GHG perspective (156 ± 264 g CO2 eq m-2), while the SRC site was a net sink of -2202 ± 792 g CO2 eq m-2. In conclusion the experiment led to a positive evaluation of the conversion of cropland to bioenergy SRC from a GHG viewpoint.

  6. Effect of drought on fine roots productivity in poplar-based short rotation coppice

    Science.gov (United States)

    Mani Tripathi, Abhishek; Fischer, Milan; Berhongaray, Gonzalo; Orság, Matěj; Trnka, Miroslav

    2015-04-01

    Short rotation woody crops (SRWC) are alternative source of bioenergy, which apart from their 'carbon neutrality' have potential to store carbon (C) into soil and mitigate the increasing CO2 emission. Studies of below ground biomass of trees are divided into two types according to root diameter - analysis of fine roots (less than 2 mm) and coarse roots (more than 2 mm). Trees roots are spatially highly heterogeneous and it requires large number of samples to obtain a representative estimate of belowground biomass. For this study we used hybrid poplar clone J-105 (Populus nigra x P. maximowiczii) grown under short rotation coppice system in the region of Bohemian-Moravian Highland (49o32'N, 16o15'E and altitude 530 m a.s.l.) since April 2000. The plantation with planting density of 9,216 trees ha-1 was established on the former agricultural land and the length of the rotation cycle was set to 6-8 years. While mean annual rainfall was 609 mm with mean annual temperature 7.2oC during 1981-2013 significant increase of temperature and more frequent droughts are expected. In 2011, we established drought experiment based on throughfall exclusion system, reducing up to 70 % of throughfall precipitation. Thus 2 treatments with normal and lowered soil moisture levels were introduced. In January and February 2014, we cored 18 places including drought and control using root bipartite auger. The main goal of the study is to assess the response of fine roots productivity and fine roots vertical distribution on the reduced soil water availability. Results will be presented at the conference. Acknowledgements: This study was funded by research project IGA Mendel University 2014 "Study of below ground biomass in short rotation poplar coppice (J-105) in the Czech-Moravian Highlands", project PASED (KONTAKT II LH12037 ʺDevelopment of models for the assessment of abiotic stresses in selected energy woody plantsʺ and "Building up a multidisciplinary scientific team focused on drought

  7. Greenhouse gas balance of cropland conversion to bioenergy poplar short-rotation coppice

    Science.gov (United States)

    Sabbatini, S.; Arriga, N.; Bertolini, T.; Castaldi, S.; Chiti, T.; Consalvo, C.; Njakou Djomo, S.; Gioli, B.; Matteucci, G.; Papale, D.

    2016-01-01

    The production of bioenergy in Europe is one of the strategies conceived to reduce greenhouse gas (GHG) emissions. The suitability of the land use change from a cropland (REF site) to a short-rotation coppice plantation of hybrid poplar (SRC site) was investigated by comparing the GHG budgets of these two systems over 24 months in Viterbo, Italy. This period corresponded to a single rotation of the SRC site. The REF site was a crop rotation between grassland and winter wheat, i.e. the same management of the SRC site before the conversion to short-rotation coppice. Eddy covariance measurements were carried out to quantify the net ecosystem exchange of CO2 (FCO2), whereas chambers were used to measure N2O and CH4 emissions from soil. The measurements began 2 years after the conversion of arable land to SRC so that an older poplar plantation was used to estimate the soil organic carbon (SOC) loss due to SRC establishment and to estimate SOC recovery over time. Emissions from tractors and from production and transport of agricultural inputs (FMAN) were modelled. A GHG emission offset, due to the substitution of natural gas with SRC biomass, was credited to the GHG budget of the SRC site. Emissions generated by the use of biomass (FEXP) were also considered. Suitability was finally assessed by comparing the GHG budgets of the two sites. CO2 uptake was 3512 ± 224 g CO2 m-2 at the SRC site in 2 years, and 1838 ± 107 g CO2 m-2 at the REF site. FEXP was equal to 1858 ± 240 g CO2 m-2 at the REF site, thus basically compensating for FCO2, while it was 1118 ± 521 g CO2 m-2 at the SRC site. The SRC site could offset 379.7 ± 175.1 g CO2eq m-2 from fossil fuel displacement. Soil CH4 and N2O fluxes were negligible. FMAN made up 2 and 4 % in the GHG budgets of SRC and REF sites respectively, while the SOC loss was 455 ± 524 g CO2 m-2 in 2 years. Overall, the REF site was close to neutrality from a GHG perspective (156 ± 264 g CO2eq m-2), while the SRC site was a net sink of

  8. Major Chromosomal Rearrangements Distinguish Willow and Poplar After the Ancestral "Salicoid" Genome Duplication.

    Science.gov (United States)

    Hou, Jing; Ye, Ning; Dong, Zhongyuan; Lu, Mengzhu; Li, Laigeng; Yin, Tongming

    2016-06-27

    Populus (poplar) and Salix (willow) are sister genera in the Salicaceae family. In both lineages extant species are predominantly diploid. Genome analysis previously revealed that the two lineages originated from a common tetraploid ancestor. In this study, we conducted a syntenic comparison of the corresponding 19 chromosome members of the poplar and willow genomes. Our observations revealed that almost every chromosomal segment had a parallel paralogous segment elsewhere in the genomes, and the two lineages shared a similar syntenic pinwheel pattern for most of the chromosomes, which indicated that the two lineages diverged after the genome reorganization in the common progenitor. The pinwheel patterns showed distinct differences for two chromosome pairs in each lineage. Further analysis detected two major interchromosomal rearrangements that distinguished the karyotypes of willow and poplar. Chromosome I of willow was a conjunction of poplar chromosome XVI and the lower portion of poplar chromosome I, whereas willow chromosome XVI corresponded to the upper portion of poplar chromosome I. Scientists have suggested that Populus is evolutionarily more primitive than Salix. Therefore, we propose that, after the "salicoid" duplication event, fission and fusion of the ancestral chromosomes first give rise to the diploid progenitor of extant Populus species. During the evolutionary process, fission and fusion of poplar chromosomes I and XVI subsequently give rise to the progenitor of extant Salix species. This study contributes to an improved understanding of genome divergence after ancient genome duplication in closely related lineages of higher plants.

  9. Enhancement of Biogas Yield of Poplar Leaf by High-Solid Codigestion with Swine Manure.

    Science.gov (United States)

    Wangliang, Li; Zhikai, Zhang; Guangwen, Xu

    2016-05-01

    The aim of this work was to examine the improvement of anaerobic biodegradability of organic fractions of poplar leaf from codigestion with swine manure (SM), thus biogas yield and energy recovery. When poplar leaf was used as a sole substrate, the cumulative biogas yield was low, about 163 mL (g volatile solid (VS))(-1) after 45 days of digestion with a substrate/inoculum ratio of 2.5 and a total solid (TS) of 22 %. Under the same condition, the cumulative biogas yield of poplar leaf reached 321 mL (g VS)(-1) when SM/poplar leaf ratio was 2:5 (based on VS). The SM/poplar leaf ratio can determine C/N ratio of the cosubstrate and thus has significant influence on biogas yield. When the SM/poplar leaf ratio was 2:5, C/N ratio was calculated to be 27.02, and the biogas yield in 45 days of digestion was the highest. The semi-continuous digestion of poplar leaf was carried out with the organic loading rate of 1.25 and 1.88 g VS day(-1). The average daily biogas yield was 230.2 mL (g VS)(-1) and 208.4 mL (g VS)(-1). The composition analysis revealed that cellulose and hemicellulose contributed to the biogas production.

  10. Phytoextraction of risk elements by willow and poplar trees.

    Science.gov (United States)

    Kacálková, Lada; Tlustoš, Pavel; Száková, Jiřina

    2015-01-01

    To characterize the phytoextraction efficiency of two clones of willow trees (Salix x smithiana Willd., Salix rubens) and two clones of poplar trees (Populus nigra x maximowiczii, Populus nigra Wolterson) were planted in contaminated soil (0.4-2.0 mg Cd.kg(-1), 78-313 mg Zn.kg(-1), 21.3-118 mg Cu.kg(-1)). Field experiment was carried out in Czech Republic. The study investigated their ability to accumulate heavy metals (Cd, Zn, and Cu) in harvestable plant parts. The poplars produced higher amount of biomass than willows. Both Salix clones accumulated higher amount of Cd, Zn and Cu in their biomass (maximum 6.8 mg Cd.kg(-1), 909 mg Zn.kg(-1), and 17.7 mg Cu.kg(-1)) compared to Populus clones (maximum 2.06 mg Cd.kg(-1), 463 mg Zn.kg(-1), and 11.8 mg Cu.kg(-1)). There were no significant differences between clones of individual species. BCs for Cd and Zn were greater than 1 (the highest in willow leaves). BCs values of Cu were very low. These results indicate that Salix is more suitable plant for phytoextraction of Cd and Zn than Populus. The Cu phytoextraction potential of Salix and Populus trees was not confirmed in this experiment due to low soil availability of this element.

  11. Enhancement of Enzymatic Saccharification of Poplar by Green Liquor Pretreatment

    Directory of Open Access Journals (Sweden)

    Xin Meng

    2014-04-01

    Full Text Available Green liquor (Na2S + Na2CO3, GL pretreatment is an effective pathway for improving the enzymatic digestibility of lignocellulosic biomass for the production of bioethanol. In this work, GL was employed as a pretreatment to enhance the enzymatic saccharification of poplar. During pretreatment, the increase of H-factor and TTA charge resulted in enhanced delignification and increased degradation of polysaccharides. The sugar yield of enzymatic hydrolysis increased rapidly with increasing TTA charge in GL pretreatment, while the effect of different H-factors (from 400 to 800 on sugar yield was unnoticeable. The pretreated solid recovery was 75.5% at a lignin removal rate of 29.2% under optimized conditions of total titratable alkali (TTA charge 20%, sulfidity 25%, and H-factor 400. The sugar yield of glucan, xylan, and total sugar of GL-pretreated poplar in enzymatic hydrolysis reached up to 89.9%, 65.5%, and 82.8%, respectively, at a cellulase loading of 40 FPU/g-cellulose.

  12. Does domestication cause changes in growth reaction norms? A study of farmed, wild and hybrid Atlantic salmon families exposed to environmental stress.

    Directory of Open Access Journals (Sweden)

    Monica Favnebøe Solberg

    Full Text Available One of the most important traits linked with the successful domestication of animals is reducing their sensitivity to environmental stressors in the human controlled environment. In order to examine whether domestication selection in Atlantic salmon Salmo salar L., over approximately ten generations, has inadvertently selected for reduced responsiveness to stress, we compared the growth reaction norms of 29 wild, hybrid and domesticated families reared together under standard hatchery conditions (control and in the presence of a stressor (reduced water level twice daily. The experiment was conducted for a 14 week period. Farmed salmon outgrew wild salmon 1:2.93 in the control tanks, and no overlap in mean weight was displayed between families representing the three groups. Thus, the elevation of the reaction norms differed among the groups. Overall, growth was approximately 25% lower in the stressed tanksl; however, farmed salmon outgrew wild salmon 1:3.42 under these conditions. That farmed salmon maintained a relatively higher growth rate than the wild salmon in the stressed tanks demonstrates a lower responsiveness to stress in the farmed salmon. Thus, flatter reaction norm slopes were displayed in the farmed salmon, demonstrating reduced plasticity for this trait under these specific experimental conditions. For all growth measurements, hybrid salmon displayed intermediate values. Wild salmon displayed higher heritability estimates for body weight than the hybrid and farmed salmon in both environments. This suggests reduced genetic variation for body weight in the farmed contra wild salmon studied here. While these results may be linked to the specific families and stocks investigated, and verification in other stocks and traits is needed, these data are consistent with the theoretical predictions of domestication.

  13. Development of the Poplar-Laccaria bicolor Ectomycorrhiza Modifies Root Auxin Metabolism, Signaling, and Response.

    Science.gov (United States)

    Vayssières, Alice; Pěnčík, Ales; Felten, Judith; Kohler, Annegret; Ljung, Karin; Martin, Francis; Legué, Valérie

    2015-09-01

    Root systems of host trees are known to establish ectomycorrhizae (ECM) interactions with rhizospheric fungi. This mutualistic association leads to dramatic developmental modifications in root architecture, with the formation of numerous short and swollen lateral roots ensheathed by a fungal mantle. Knowing that auxin plays a crucial role in root development, we investigated how auxin metabolism, signaling, and response are affected in poplar (Populus spp.)-Laccaria bicolor ECM roots. The plant-fungus interaction leads to the arrest of lateral root growth with simultaneous attenuation of the synthetic auxin response element DR5. Measurement of auxin-related metabolites in the free-living partners revealed that the mycelium of L. bicolor produces high concentrations of the auxin indole-3-acetic acid (IAA). Metabolic profiling showed an accumulation of IAA and changes in the indol-3-pyruvic acid-dependent IAA biosynthesis and IAA conjugation and degradation pathways during ECM formation. The global analysis of auxin response gene expression and the regulation of AUXIN SIGNALING F-BOX PROTEIN5, AUXIN/IAA, and AUXIN RESPONSE FACTOR expression in ECM roots suggested that symbiosis-dependent auxin signaling is activated during the colonization by L. bicolor. Taking all this evidence into account, we propose a model in which auxin signaling plays a crucial role in the modification of root growth during ECM formation.

  14. Soils organic C sequestration under poplar and willow agroforestry systems

    Science.gov (United States)

    Gunina, Anna; Tariq, Azeem; Lamersdorf, Norbert

    2015-04-01

    Short rotation coppices (SRC) as monocultures or as agroforestry (AF) applications (e.g. alley cropping) are two techniques to implement forest into agricultural practices. Despite afforestation promotes soil carbon (C) accumulation, age and type of the tree stand can affect the C accumulation in different degrees. Here, we studied the impact of afforestation on C accumulation for: i) pure SCR of willow (Salix viminalis x Salix schwerinii) and poplar (Populus nigra x Populus maximowiczii) and ii) AF cropping system with willow. Forest systems have been established within the BEST agroforestry project in Germany. Adjacent agricultural field have been used as a control. Soil samples were collected in 2014, three years after plantation establishment, from three soil depths: 0-3, 3-20, and 20-30 cm. Total organic C, labile C (incubation of 20 g soil during 100 days with measuring of CO2) and aggregate structure were analysed. Additionally, density fractionation of the samples from 0-3 cm was applied to separate particulate organic matter (POM) and mineral fractions. Aggregates and density fractions were analyzed for C content. High input of plant litter as well as root exudates have led to increases of organic C in AF and SRC plots compare to cropland, mainly in the top 0-3 cm. The highest C content was found for willow SRC (18.2 g kg-1 soil), followed by willow-AF (15.6 g kg-1 soil), and poplar SRC (13.7 g kg-1 soil). Carbon content of cropland was 12.5 g kg-1 soil. Absence of ploughing caused increase portion of macroaggregates (>2000 μm) under SRC and AF in all soil layers as well as the highest percentage of C in that aggregate size class (70-80%). In contrast, C in cropland soil was mainly accumulated in small macroaggregates (250-2000 μm). Intensive mineralisation of fresh litter and old POM, taking place during first years of trees development, resulted to similar portions of free POM for willow AF, willow SRC and cropland (8%), and even lower ones for poplar

  15. Growth of GaN@InGaN Core-Shell and Au-GaN Hybrid Nanostructures for Energy Applications

    Directory of Open Access Journals (Sweden)

    Tevye Kuykendall

    2009-01-01

    Full Text Available We demonstrated a method to control the bandgap energy of GaN nanowires by forming GaN@InGaN core-shell hybrid structures using metal organic chemical vapor deposition (MOCVD. Furthermore, we show the growth of Au nanoparticles on the surface of GaN nanowires in solution at room temperature. The work shown here is a first step toward engineering properties that are crucial for the rational design and synthesis of a new class of photocatalytic materials. The hybrid structures were characterized by various techniques, including photoluminescence (PL, energy dispersive x-ray spectroscopy (EDS, transmission and scanning electron microscopy (TEM and SEM, and x-ray diffraction (XRD.

  16. EFFECT OF INTEGRATED NUTRIENT MANAGEMENT ON VEGETATIVE GROWTH AND YIELD OF TRANSPLANTED HYBRID RICE (ORYZA SATIVA L. CROP

    Directory of Open Access Journals (Sweden)

    RAYEES A. SHAH* SANDEEP KUMAR

    2014-09-01

    Full Text Available The integrated use of organic and inorganic sources of plant nutrients can help in sustainable and environmentally sound nutrient management of soils that are low in organic matter. A study was conducted  during 2009- 10 & 2010-11, on sandy loam soils, low in organic carbon, medium in available phosphorus and potash with pH of 7.5 at Agricultural Research Farm of C.C.R.(P.G. College, Muzaffarnagar U.P. India, to investigate the comparative use of  integrated nutrient management on vegetative growth and yield of hybrid rice. The experiment was laid out with fifteen treatments in a RBD. The treatments were; Control (T1, NPK 100% RDF (T2, NPK 75% RDF (T3, NPK 50% RDF + FYM @ 10 tons  ha-1 (T4, NPK 50% RDF + FYM @15 tons ha-1 (T5, NPK 50% RDF + wheat cut straw @10 tons ha-1 (T6, NPK 50% RDF + wheat cut straw @15 tons ha-1 (T7, NPK 50% RDF + Neem cake @ 2.5 tones ha-1 (T8, NPK 50% RDF + Neem cake @ 5 tones ha-1 (T9, NPK 50% RDF + Vermicompost @ 2.5 tons ha-1 (T10, NPK 50% RDF + Vermicompost @ 2.5 tons ha-1 +Azotobacter (T11, NPK 50% RDF + Vermicompost @ 2.5 tones ha-1 +PSB @ 5Kg ha-1 (T12, NPK 50% RDF + Vermicompost @ 2.5 tones ha-1 + Azospirillum (T13, NPK 50% RDF  + Azotobacter + Azospirillum + PSB @ 5 Kg ha-1(T14, and NPK 50% RDF + Neem cake @ 2.5 tones ha-1 +FYM @5 tons  ha-1 + Azotobacter+PSB @ 5Kg ha-1 (T15. The maximum grain yield (63 and 67 q per hectare during 2009 and 2010, respectively was obtained with the integration of NPK 50% RDF + Neem cake @2.5 tonnes ha-1 + FYM @5 tonnes ha-1+Azotobacter+PSB @ 5kg ha-1.

  17. UAV-Based Thermal Imaging for High-Throughput Field Phenotyping of Black Poplar Response to Drought

    Directory of Open Access Journals (Sweden)

    Riccardo Ludovisi

    2017-09-01

    Full Text Available Poplars are fast-growing, high-yielding forest tree species, whose cultivation as second-generation biofuel crops is of increasing interest and can efficiently meet emission reduction goals. Yet, breeding elite poplar trees for drought resistance remains a major challenge. Worldwide breeding programs are largely focused on intra/interspecific hybridization, whereby Populus nigra L. is a fundamental parental pool. While high-throughput genotyping has resulted in unprecedented capabilities to rapidly decode complex genetic architecture of plant stress resistance, linking genomics to phenomics is hindered by technically challenging phenotyping. Relying on unmanned aerial vehicle (UAV-based remote sensing and imaging techniques, high-throughput field phenotyping (HTFP aims at enabling highly precise and efficient, non-destructive screening of genotype performance in large populations. To efficiently support forest-tree breeding programs, ground-truthing observations should be complemented with standardized HTFP. In this study, we develop a high-resolution (leaf level HTFP approach to investigate the response to drought of a full-sib F2 partially inbred population (termed here ‘POP6’, whose F1 was obtained from an intraspecific P. nigra controlled cross between genotypes with highly divergent phenotypes. We assessed the effects of two water treatments (well-watered and moderate drought on a population of 4603 trees (503 genotypes hosted in two adjacent experimental plots (1.67 ha by conducting low-elevation (25 m flights with an aerial drone and capturing 7836 thermal infrared (TIR images. TIR images were undistorted, georeferenced, and orthorectified to obtain radiometric mosaics. Canopy temperature (Tc was extracted using two independent semi-automated segmentation techniques, eCognition- and Matlab-based, to avoid the mixed-pixel problem. Overall, results showed that the UAV platform-based thermal imaging enables to effectively assess genotype

  18. Histone Acetylation Modifications Affect Tissue-Dependent Expression of Poplar Homologs of C4 Photosynthetic Enzyme Genes

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    Yuan Li

    2017-06-01

    Full Text Available Histone modifications play important roles in regulating the expression of C4 photosynthetic genes. Given that all enzymes required for the C4 photosynthesis pathway are present in C3 plants, it has been hypothesized that this expression regulatory mechanism has been conserved. However, the relationship between histone modification and the expression of homologs of C4 photosynthetic enzyme genes has not been well determined in C3 plants. In the present study, we cloned nine hybrid poplar (Populus simonii × Populus nigra homologs of maize (Zea mays C4 photosynthetic enzyme genes, carbonic anhydrase (CA, pyruvate orthophosphate dikinase (PPDK, phosphoenolpyruvate carboxykinase (PCK, and phosphoenolpyruvate carboxylase (PEPC, and investigated the correlation between the expression levels of these genes and the levels of promoter histone acetylation modifications in four vegetative tissues. We found that poplar homologs of C4 homologous genes had tissue-dependent expression patterns that were mostly well-correlated with the level of histone acetylation modification (H3K9ac and H4K5ac determined by chromatin immunoprecipitation assays. Treatment with the histone deacetylase inhibitor trichostatin A further confirmed the role of histone acetylation in the regulation of the nine target genes. Collectively, these results suggest that both H3K9ac and H4K5ac positively regulate the tissue-dependent expression pattern of the PsnCAs, PsnPPDKs, PsnPCKs, and PsnPEPCs genes and that this regulatory mechanism seems to be conserved among the C3 and C4 species. Our findings provide new insight that will aid efforts to modify the expression pattern of these homologs of C4 genes to engineer C4 plants from C3 plants.

  19. The effects of high-tannin leaf litter from transgenic poplars on microbial communities in microcosm soils.

    Directory of Open Access Journals (Sweden)

    Richard S. Winder

    2013-09-01

    Full Text Available The impacts of leaf litter from genetically-modified hybrid poplar accumulating high levels of condensed tannins (proanthocyanidins were examined in soil microcosms consisting of moss growing on sieved soil. Moss preferentially proliferated in microcosms with lower tannin content; DGGE detected increased fungal diversity in microcosms with low-tannin litter. The proportion of cloned rDNA sequences from Actinobacteria decreased with litter addition while Bacteroidetes, Chloroflexi, Cyanobacteria, and α-Proteobacteria significantly increased. β–Proteobacteria were proportionally more numerous at high tannin levels. Tannins had no significant impact on overall diversity of bacterial communities analyzed with various estimators. There was an increased proportion of N-fixing bacteria corresponding to the addition of litter with low tannin levels. The addition of litter increased the proportion of Ascomycota/Basidiomycota. Dothideomycetes, Pucciniomycetes, and Tremellomycetes also increased and Agaricomycetes decreased. Agaricomycetes and Sordariomycetes were significantly more abundant in controls, whereas Pucciniomycetes increased in soil with litter from transformed trees (P = 0.051. Richness estimators and diversity indices revealed no significant difference in the composition of fungal communities; PCoA partitioned the fungal communities into three groups: (i those with higher amounts of added tannin from both transformed and untransformed treatments, (ii those corresponding to soils without litter, and (iii those corresponding to microcosms with litter added from trees transformed only with a β-glucuronidase (GUS control vector. While the litter from transformed poplars had significant effects on soil microbe communities, the observed impacts reflected known impacts on soil processes associated with tannins, and were similar to changes that would be expected from natural variation in tannin levels.

  20. Wettability of poplar leaves influences dew formation and infection by Melampsora larici-populina

    National Research Council Canada - National Science Library

    Pinon, Jean; Frey, Pascal; Husson, Claude

    2006-01-01

    .... The frequency and duration of dew on these clones were recorded in two nurseries. Black poplar leaves had the highest wettability, with relatively flat-shaped water droplets and a short drying time, in both the laboratory and nursery...

  1. Response of ecosystem carbon fluxes to drought events in a poplar plantation in Northern China

    Science.gov (United States)

    Jie Zhou; Zhiqiang Zhang; Ge Sun; Xianrui Fang; Tonggang Zha; Steve McNulty; Jiquan Chen; Ying Jin; Asko Noormets

    2013-01-01

    Poplar plantations are widely used for timber production and ecological restoration in northern China,a region that experiences frequent droughts and water scarcity. An open-path eddy-covariance (EC)system was used to continuously measure the carbon,water,and energy fluxes in a poplar plantation during the growing season (i.e., April–October)over the period 2006–2008...

  2. Non-cytotoxic organic-inorganic hybrid bioscaffolds: An efficient bedding for rapid growth of bone-like apatite and cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    John, Lukasz, E-mail: lukasz.john@chem.uni.wroc.pl [Faculty of Chemistry, University of Wroclaw, 14 F. Joliot-Curie, 50-383 Wroclaw (Poland); Baltrukiewicz, Marta; Sobota, Piotr [Faculty of Chemistry, University of Wroclaw, 14 F. Joliot-Curie, 50-383 Wroclaw (Poland); Brykner, Renata; Cwynar-Zajac, Lucja [Department of Histology and Embryology, Wroclaw Medical University, 6a Chalubinskiego, 50-368 Wroclaw (Poland); Dziegiel, Piotr [Department of Histology and Embryology, Wroclaw Medical University, 6a Chalubinskiego, 50-368 Wroclaw (Poland); Department of Histology and Embryology, Poznan University of Medical Sciences, 6 Swiecickiego, 61-781 Poznan (Poland)

    2012-10-01

    Synthesis and characterization of organic-inorganic macroporous hybrid scaffolds were investigated. The materials were prepared by combining 2-hydroxyethylmethacrylate (HEMA) and triethoxyvinylsilane (TEVS) chemically modified by Ca{sup 2+} and PO{sub 4}{sup 3-} ions via sol-gel route. In this study we have constructed a sugar-based cracks-free three-dimensional (3D) network with interconnected porous architecture within the range of 150-300 {mu}m and rough topography. The obtained results revealed that both topography and composition of prepared materials allow rapid growth of the bone-like apatite (HAp) layer on their surface after soaking in biological medium. Preliminary studies have shown that hybrids covered by HAp are non-cytotoxic and allow cell proliferation that make them a promising scaffolds in the field of bone regenerative medicine. The materials were mainly characterized by powder X-ray diffraction analysis (PXRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy-energy-dispersive spectroscopy (SEM-EDS) and transmission electron microscopy-energy-dispersive spectroscopy (TEM-EDS). Highlights: Black-Right-Pointing-Pointer Sol-gel derived biomaterials. Black-Right-Pointing-Pointer 3D organic-inorganic hybrid composites for bone tissue engineering. Black-Right-Pointing-Pointer Sugar-templated cracks-free macroporous scaffolds. Black-Right-Pointing-Pointer 2-hydroxyethylmethacrylate/triethoxyvinylsilane blend doped with calcium and phosphate ions. Black-Right-Pointing-Pointer Non-cytotoxic bedding for fibroblasts proliferation.

  3. Expression and molecular evolution of two DREB1 genes in black poplar (Populus nigra).

    Science.gov (United States)

    Chu, Yanguang; Huang, Qinjun; Zhang, Bingyu; Ding, Changjun; Su, Xiaohua

    2014-01-01

    Environmental stresses such as low temperature, drought, and high salinity significantly affect plant growth and yield. As selective forces, these adverse factors play essential roles in shaping phenotypic variation in plant populations. Black poplar (Populus nigra) is an economically and ecologically important forest tree species with widely distributed populations and is thus suitable for experiments detecting evolutionary footprints left by stress. Here, we performed expression and evolutionary analysis of two duplicated DREB A1-subgroup (DREB1) genes, PnDREB68 and PnDREB69, encoding transcription factors that are involved in stress responses. The two genes showed partially overlapping but distinct expression patterns in response to stresses. These genes were strongly and rapidly induced by cold stress in leaves, stems, and roots. In leaf tissue, dehydration stress induced the expression of PnDREB68 but not PnDREB69. PnDREB69 displayed more rapid responses and longer expression durations than PnDREB68 under salt and ABA stress, respectively. Based on single nucleotide polymorphism (SNP) analysis, we found significant population genetic differentiation, with a greater FST value (0.09189) for PnDREB69 than for PnDREB68 (0.07743). Nucleotide diversity analysis revealed a two-fold higher πT for PnDREB68 than for PnDREB69 (0.00563 vs. 0.00243), reflecting strong purifying selection acting on the former. The results suggest that positive selection acted on PnDREB69, as evidenced by neutral testing using Tajima's D statistic. The distinct selective forces to which each of the genes was subjected may be associated with expression divergence. Linkage disequilibrium (LD) was low for the sequenced region, with a higher level for PnDREB68 than for PnDREB69. Additionally, analysis of the relationship among carbon isotope ratios, SNP classes and gene expression, together with motif and domain analysis, suggested that 14 polymorphisms within the two genes may be candidates

  4. Expression and molecular evolution of two DREB1 genes in black poplar (Populus nigra.

    Directory of Open Access Journals (Sweden)

    Yanguang Chu

    Full Text Available Environmental stresses such as low temperature, drought, and high salinity significantly affect plant growth and yield. As selective forces, these adverse factors play essential roles in shaping phenotypic variation in plant populations. Black poplar (Populus nigra is an economically and ecologically important forest tree species with widely distributed populations and is thus suitable for experiments detecting evolutionary footprints left by stress. Here, we performed expression and evolutionary analysis of two duplicated DREB A1-subgroup (DREB1 genes, PnDREB68 and PnDREB69, encoding transcription factors that are involved in stress responses. The two genes showed partially overlapping but distinct expression patterns in response to stresses. These genes were strongly and rapidly induced by cold stress in leaves, stems, and roots. In leaf tissue, dehydration stress induced the expression of PnDREB68 but not PnDREB69. PnDREB69 displayed more rapid responses and longer expression durations than PnDREB68 under salt and ABA stress, respectively. Based on single nucleotide polymorphism (SNP analysis, we found significant population genetic differentiation, with a greater FST value (0.09189 for PnDREB69 than for PnDREB68 (0.07743. Nucleotide diversity analysis revealed a two-fold higher πT for PnDREB68 than for PnDREB69 (0.00563 vs. 0.00243, reflecting strong purifying selection acting on the former. The results suggest that positive selection acted on PnDREB69, as evidenced by neutral testing using Tajima's D statistic. The distinct selective forces to which each of the genes was subjected may be associated with expression divergence. Linkage disequilibrium (LD was low for the sequenced region, with a higher level for PnDREB68 than for PnDREB69. Additionally, analysis of the relationship among carbon isotope ratios, SNP classes and gene expression, together with motif and domain analysis, suggested that 14 polymorphisms within the two genes may be

  5. FEM growth and yield data monocultures - other species

    NARCIS (Netherlands)

    Goudzwaard, L.; Jansen, J.J.; Oosterbaan, A.; Oldenburger, J.F.; Mohren, G.M.J.; Ouden, den J.

    2016-01-01

    The current database is part of the FEM growth and yield database, a collection of growth and yield data from even-aged monocultures (douglas fir, common oak, poplar, Japanese Larch, Norway spruce, Scots pine, Corsican pine, Austrian pine, red oak and several other species, with only a few plots,

  6. FEM growth and yield data mixed species forest

    NARCIS (Netherlands)

    Bartelink, H.H.; Jansen, J.J.; Goudzwaard, L.; Lu, Huicui; Oldenburger, J.F.; Mohren, G.M.J.; Ouden, den J.

    2016-01-01

    The current database is part of the FEM growth and yield database, a collection of growth and yield data from even-aged monocultures (douglas fir, common oak, poplar, Japanese Larch, Norway spruce, Scots pine, Corsican pine, Austrian pine, red oak and several other species with only a few plots like

  7. Dechlorination of PCBs in the rhizosphere of switchgrass and poplar.

    Science.gov (United States)

    Meggo, Richard E; Schnoor, Jerald L; Hu, Dingfei

    2013-07-01

    Polychlorinated biphenyl (PCB) congeners (PCB 52, 77, and 153) singly and in mixture were spiked and aged in soil microcosms and subsequently planted with switchgrass (Panicum virgatum) or poplar (Populus deltoids x nigra DN34). The planted reactors showed significantly greater reductions in PCB parent compounds when compared to unplanted systems after 32 weeks. There was evidence of reductive dechlorination in both planted and unplanted systems, but the planted microcosms with fully developed roots and rhizospheres showed greater biotransformation than the unplanted reactors. These dechlorination products accounted for approximately all of the molar mass of parent compound lost. Based on the transformation products, reductive dechlorination pathways are proposed for rhizospheric biotransformation of PCB 52, 77, and 153. This is the first report of rhizosphere biotransformation pathways for reductive dechlorination in marginally aerobic, intermittently flooded soil as evidenced by a mass balance on transformation products.

  8. Wood Microstructure Effects on Chinese White Poplar Dyeing

    Institute of Scientific and Technical Information of China (English)

    DUANXinfang; BAOFucheng

    2004-01-01

    In order to study the influence of wood microstructure on wood dyeing, eleven parameters of wood microstructure and 5 parameters of wood dyeing effects for 34 pieces of wood boards from 5 trees of Chinese white poplar (Populus tornentosa) were determined and the multiple regression analysis between the factors of wood microstructures and the parameters of wood dyeing effects were made. The regression results show that each variable of wood dyeing effects has higher relationship with wood microstructures,and multiple correlation coefficients between each variable of wood dyeing effects and wood microstructures are 0.483 6-0.799 8. The main factors of wood microstructures influencing wood dyeing of Chinese whitep oplar are proportion of wood ray, proportion of vessel and proportion of wood fiber according to comparing the standardized regression coefficients of multiple regression equation.

  9. Quantification of carbon sources for isoprene emission in poplar leaves

    Science.gov (United States)

    Kreutzwieseer, J.; Graus, M.; Schnitzler, J. P.; Heizmann, U.; Rennenberg, H.; Hansel, A.

    2003-12-01

    Isoprene is the most abundant volatile organic compound emitted by plants and in particular by trees. Current interest in understanding its biosynthesis in chloroplasts is forced by the important role isoprene plays in atmospheric chemistry. Leaf isoprene formation is closely linked to photosynthesis by a dynamic use of recently fixed photosynthetic precursors in the chloroplast. Under steady state conditions in [13C]CO2 atmosphere approximately 75 % of isoprene became labeled within minutes. The source of unlabeled C is suggested to be of extra-chloroplastidic and/or from starch degradation. In order to test whether these alternative carbon sources - leaf internal C-pools and xylem-transported carbohydrates, contribute to leaf isoprene formation in poplar (Populus tremula x P. alba) on-line proton-transfer-reaction-mass spectrometry (PTR-MS) was used to follow 13C-labeling kinetics.

  10. Lead Tolerance and Accumulation in White Poplar Cultivated In Vitro

    Directory of Open Access Journals (Sweden)

    Branislav Kovačević

    2013-06-01

    Full Text Available Background and Purpose: This paper analyses the lead tolerance and accumulation in white poplar genotypes in vitro, in order to optimize genotype evaluation and other procedures in their implementation in phytoremediation projects and landscaping in areas endangered by lead accumulation. Material and Methods: The lead tolerance and accumulation of five white poplar genotypes after 35 days in vitro cultivation on media supplemented with lead was examined. The following Pb(NO32 concentrations were used: 0, 10-6, 10-5, 10-4 and 10-3 M. Tolerance analysis (described by tolerance indices was based on morphological parameters, biomass accumulation and the content of photosynthetic pigments, while lead accumulation was described by shoot lead accumulation and shoot lead content. Results and Conclusions: The chosen lead concentrations appeared not to be lethal. Moreover, the obtained results showed that the tested lead concentrations had a positive effect on: number of formed roots, shoot moisture content and shoot height. The best differentiation among the examined genotypes was gained by the tolerance index based on the shoot height on 10-4 M Pb(NO32. The shoot lead accumulation and shoot lead content significantly increased on 10-4 and 10-3 M Pb(NO32 media. Thus, the concentration of 10-4 M Pb(NO32 is recommended for further research. Two examined genotypes of horticultural value (LCM and LBM achieved a significantly higher lead shoot content compared to the wide spread genotype “Villafranca” (almost 200% and 125% higher, respectively.

  11. Storage Problems of Poplar Chips from Short Rotation Plantations with Special Emphasis on Fungal Development

    Directory of Open Access Journals (Sweden)

    HORVÁTH, Zsuzsanna

    2012-01-01

    Full Text Available There are several problems in storing wood chips freshly harvested from short rotation plantations, which result in quality losses as well as in dry matter and energy losses. The factors influencing the degradation of raw material are examined in this paper with special focus on fungal development. An excessive growth of fungi is connected to dry matter losses and also to an increased health risk during raw material handling.The following factors were measured during 6 months storage of poplar wood chips depending on particle size: box temperature, moisture content, pH-value, appearance of fungi in the storage and the concentration of fungal particles in the air. The results show a close connection between particle size, temperature and attack of fungi. During the storage mesophilic and termophilic species of the genera Alternaria, Aspergillus, Cladosporium, Mucor and Penicillium appeared. The concentration of fungal particles is the highest for fine chips and decreases in bigger particles. There was a special focus on the investigation of the properties of coarse chips (G 50, which represent a good compromise between handling, storage losses and health risk due to fungal development.

  12. Quantitative Proteomic and Phosphoproteomic Approaches for Deciphering the Signaling Pathway for Tension Wood Formation in Poplar.

    Science.gov (United States)

    Mauriat, Mélanie; Leplé, Jean-Charles; Claverol, Stéphane; Bartholomé, Jérôme; Negroni, Luc; Richet, Nicolas; Lalanne, Céline; Bonneu, Marc; Coutand, Catherine; Plomion, Christophe

    2015-08-07

    Trees adjust their growth following forced changes in orientation to re-establish a vertical position. In angiosperms, this adjustment involves the differential regulation of vascular cambial activity between the lower (opposite wood) and upper (tension wood) sides of the leaning stem. We investigated the molecular mechanisms leading to the formation of differential wood types through a quantitative proteomic and phosphoproteomic analysis on poplar subjected to a gravitropic stimulus. We identified and quantified 675 phosphopeptides, corresponding to 468 phosphoproteins, and 3 763 nonphosphorylated peptides, corresponding to 1 155 proteins, in the differentiating xylem of straight-growing trees (control) and trees subjected to a gravitational stimulus during 8 weeks. About 1% of the peptides were specific to a wood type (straight, opposite, or tension wood). Proteins quantified in more than one type of wood were more numerous: a mixed linear model showed 389 phosphopeptides and 556 proteins to differ in abundance between tension wood and opposite wood. Twenty-one percent of the phosphoproteins identified here were described in their phosphorylated form for the first time. Our analyses revealed remarkable developmental molecular plasticity, with wood type-specific phosphorylation events, and highlighted the involvement of different proteins in the biosynthesis of cell wall components during the formation of the three types of wood.

  13. Effects of high temperature on photosynthesis and related gene expression in poplar

    Science.gov (United States)

    2014-01-01

    Background High temperature, whether transitory or constant, causes physiological, biochemical and molecular changes that adversely affect tree growth and productivity by reducing photosynthesis. To elucidate the photosynthetic adaption response and examine the recovery capacity of trees under heat stress, we measured gas exchange, chlorophyll fluorescence, electron transport, water use efficiency, and reactive oxygen-producing enzyme activities in heat-stressed plants. Results We found that photosynthesis could completely recover after less than six hours of high temperature treatment, which might be a turning point in the photosynthetic response to heat stress. Genome-wide gene expression analysis at six hours of heat stress identified 29,896 differentially expressed genes (15,670 up-regulated and 14,226 down-regulated), including multiple classes of transcription factors. These interact with each other and regulate the expression of photosynthesis-related genes in response to heat stress, controlling carbon fixation and changes in stomatal conductance. Heat stress of more than twelve hours caused reduced electron transport, damaged photosystems, activated the glycolate pathway and caused H2O2 production; as a result, photosynthetic capacity did not recover completely. Conclusions This study provides a systematic physiological and global gene expression profile of the poplar photosynthetic response to heat stress and identifies the main limitations and threshold of photosynthesis under heat stress. It will expand our understanding of plant thermostability and provides a robust dataset for future studies. PMID:24774695

  14. Quarterly Progress Report on the Biological Monitoring Program for East Fork Poplar Creek

    Energy Technology Data Exchange (ETDEWEB)

    Adams, S.M.; Ashwood, T.L.; Cicerone, D.S.; Greeley, M.S. Jr.; Hill, W.R.; Kszos, L.A.

    1996-12-30

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit, a Biological Monitoring and Abatement Program ( BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Lear et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity of EFPC. These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumulation studies, and (4) ecological surveys of the periphyton, benthic macroinvertebrate, and fish communities.

  15. Natural infectious behavior of the urediniospores of Melampsora larici-populina on poplar leaves

    Institute of Scientific and Technical Information of China (English)

    Zhibing Wan; Yiran Li; Min Liu; Yingnan Chen; Tongming Yin

    2015-01-01

    The uredinial stage in the life cycle of Me-lampsora larici-populina on poplar leaves is the most important pathogenic phase. We captured partial phases of uredinial infection in the wild, aiming to reconstruct the process of uredinial ontogeny by using scanning and transmission electron microscope. At the initial infection stage, germ tubes germinated from the echinulate uredini-ospores. Germ tubes were frequently seen to merge with the leaf surface and cuticle breakage was observed, indi-cating direct hyphal penetration. Stomata penetration occurred commonly, sometimes with more than one germ tube penetrating the same stoma. Melampsora larici-pop-ulina did not form appressoria in the infection process, implying that infectious behavior of this pathogen may differ from the other rust pathogens. In general, germ tubes branched randomly, and no distinct evidence indicated that stoma could induce or orient germ tube branches. How-ever, oriented germ tube growth has been occasionally observed in other studies. The urediniospores collapsed and finally wizened when they became nutrient stressed. At the last stage of infection, the uredinia erupted from the leaf epidermis and appeared as orange pustules on the leaf surface.

  16. Selection of hybrids and edible citrus species with a high content in the diosmin functional compound. Modulating effect of plant growth regulators on contents.

    Science.gov (United States)

    Marín, F R; Del Río, J A

    2001-07-01

    The purpose of this study is to identify species, hybrids, and cultivars of edible Citrus species with high contents of diosmin as a functional compound and also to identify the developmental progress of the fruit in which it reaches maximum levels; these findings would be useful for extraction purposes and for the modulating effect of plant growth regulators on diosmin content to increase the level of this flavone. The results obtained reveal that the highest contents of diosmin are present in immature fruits of certain varieties of citron (Buda's finger) and lemon (Meyer), whereas the contents in the edible parts of the fruits are irrelevant from a pharmacological point of view. Similarly, it is shown that it is possible to increase the content of this flavone using hormonal treatments (6-benzylaminopurine and 2,4-dichlorophenoxyacetic acid) during the early stages of fruit growth.

  17. Polymer crystallization as a tool to pattern hybrid nanostructures: growth of 12 nm ZnO arrays in poly(3-hexylthiophene).

    Science.gov (United States)

    Saberi Moghaddam, Reza; Huettner, Sven; Vaynzof, Yana; Ducati, Caterina; Divitini, Giorgio; Lohwasser, Ruth H; Musselman, Kevin P; Sepe, Alessandro; Scherer, Maik R J; Thelakkat, Mukundan; Steiner, Ullrich; Friend, Richard H

    2013-09-11

    Well-ordered hybrid materials with a 10 nm length scale are highly desired. We make use of the natural length scale (typically 10-15 nm) of the alternating crystalline and amorphous layers that are generally found in semicrystalline polymers to direct the growth of a semiconducting metal oxide. This approach is exemplified with the growth of ZnO within a carboxylic acid end-functionalized poly(3-hexylthiophene) (P3HT-COOH). The metal-oxide precursor vapors diffuse into the amorphous parts of the semicrystalline polymer so that sheets of ZnO up to 0.5 μm in size can be grown. This P3HT-ZnO nanostructure further functions as a donor-acceptor photovoltaic system, with length scales appropriate for charge photogeneration.

  18. Lead uptake increases drought tolerance of wild type and transgenic poplar (Populus tremula x P. alba) overexpressing gsh 1.

    Science.gov (United States)

    Samuilov, Sladjana; Lang, Friedericke; Djukic, Matilda; Djunisijevic-Bojovic, Danijela; Rennenberg, Heinz

    2016-09-01

    Growth and development of plants largely depends on their adaptation ability in a changing climate. This is particularly true on heavy metal contaminated soils, but the interaction of heavy metal stress and climate on plant performance has not been intensively investigated. The aim of the present study was to elucidate if transgenic poplars (Populus tremula x P. alba) with enhanced glutathione content possess an enhanced tolerance to drought and lead (Pb) exposure (single and in combination) and if they are good candidates for phytoremediation of Pb contaminated soil. Lead exposure reduced growth and biomass accumulation only in above-ground tissue of wild type poplar, although most of lead accumulated in the roots. Drought caused a decline of the water content rather than reduced biomass production, while Pb counteracted this decline in the combined exposure. Apparently, metals such as Pb possess a protective function against drought, because they interact with abscisic acid dependent stomatal closure. Lead exposure decreased while drought increased glutathione content in leaves of both plant types. Lead accumulation was higher in the roots of transgenic plants, presumably as a result of chelation by glutathione. Water deprivation enhanced Pb accumulation in the roots, but Pb was subject to leakage out of the roots after re-watering. Transgenic plants showed better adaptation under mild drought plus Pb exposure partially due to improved glutathione synthesis. However, the transgenic plants cannot be considered as a good candidate for phytoremediation of Pb, due to its small translocation to the shoots and its leakage out of the roots upon re-watering.

  19. Growth window and effect of substrate symmetry in hybrid molecular beam epitaxy of a Mott insulating rare earth titanate

    Energy Technology Data Exchange (ETDEWEB)

    Moetakef, Pouya; Zhang, Jack Y.; Raghavan, Santosh; Kajdos, Adam P.; Stemmer, Susanne [Materials Department, University of California, Santa Barbara, California, 93106-5050 (United States)

    2013-07-15

    The conditions for the growth of stoichiometric GdTiO{sub 3} thin films by molecular beam epitaxy (MBE) are investigated. It is shown that relatively high growth temperatures (>750 Degree-Sign C) are required to obtain an MBE growth window in which only the stoichiometric film grows for a range of cation flux ratios. This growth window narrows with increasing film thickness. It is also shown that single-domain films are obtained by the growth on a symmetry-matched substrate. The influence of lattice mismatch strain on the electrical and magnetic characteristics of the GdTiO{sub 3} thin film is investigated.

  20. Performance and variability patterns in wood properties and growth traits in the parents, F1 and F2 generation hybrid clones of Populus deltoides

    Institute of Scientific and Technical Information of China (English)

    P. K. Pande; R. C. Dhiman

    2011-01-01

    The performance and variability patterns in the wood ele- ment's dimensions, specific gravity and growth parameters namely ramet height and GBH were evaluated in 16 clones of parents, F1 and F2 hy- brids of Populus deltoides Bartr. Ex Marsh. Ramet radial variations were non-significant, while inter-clonal variations due to interaction of clone/replication were significant for all the wood traits except vessel element length. Inter-clonal variations were significant only for fiber length and fiber wall thickness. Fiber length and specific gravity were significantly higher in female, while wall thickness and vessel element length were higher in male clones. Female parents (G48 and S7C8) showed higher flber length and specific gravity than of the male parent (G3), while vessel diameter and wall thickness were higher in male par- ent (G3). There is not much difference in fiber length and vessel ele- ment's dimensions among the parents, F1 and F2 generation hybrid clones. Specific gravity did not showed any trend for parents, F1 and F2 generations. Generally female clones showed higher growth rate. Broad sense heritability for wood traits ranged from 0.143 (fiber length) to 0.505 (fiber wall thickness), while for growth Waits it was 0.374 (GBH) and 0.418 (height). Genetic gain for all the wood and growth traits was positive for most of the wood waits. The highly divergent male clone (78) and female clones (S7C8, G48, W/A 49) in number of combinations could be used for developing new hybrids of desired wood traits to de- velop new clones.

  1. Isolation and analysis of a TIR-specific promoter from poplar

    Institute of Scientific and Technical Information of China (English)

    Zheng Hui-quan; Lin Shan-zhi; Zhang Qian; Zhang Zhen-zhen; Zhang Zhi-yi; Lei Yang; Hou Lu

    2007-01-01

    A 5'flanking region of the well-conserved Toll/interleukin-1 receptor domain (TIR)-encoding sequence was isolated from the genomic DNA of Melampsora magnusiana Wagner resistant clones of hybrid triploid poplars [(Populus tomentosa × P. bolleana)× P. tomentosa]. Sequencing results and alignment analysis show that the obtained TIR-specific promoter (named as PtTIRp01) was 1,732 bp in length; moreover 3'region of the PtTIRp01 contains a 398 bp complete TIR-encoding sequence, which significantly corresponds to the 5'composition of TIR-NBS type gene PtDRG02, indicating that the obtained TIR-specific promoter region consists of 747 bp long 5'region of TIR-NBS type gene PtDRG02 and its upstream region of promoter (985 bp). It was found that the 5'region of TIR-NBS type gene PtDRG02 was characterized in the downstream region of the transcriptional start, named as 5'-untranslated region (5'UTR), consisting of one 93 bp 5'-untranslation exon, one 213 bp intron and one 441 bp TIR-encoding open reading frame (ORF). In addition, several putative cis-acting motifs were present in the obtained TIR-specific promoter of PtDRG02,including one TATA box, one GC-rich, one AT-rich, one P-box, one 3-AF1 binding site, two CAAT boxes, two GT-1 motifs, three typical W-boxes, four Ⅰ-boxes, and one multi-cis-acting fragment (MCF). The latter contains five types of regulatory elements (E4,G-box, ABRE motif, boxl and HVAls), most of which were homologous to the cis-acting regulatory elements involved in the activation of defense genes in plants. Thus, it can be suggested that TIR-specific promoter might be a pathogen-inducible promoter and be necessary for the inducible expression of defense-related genes.

  2. Carbon isotope compositions (δ(13) C) of leaf, wood and holocellulose differ among genotypes of poplar and between previous land uses in a short-rotation biomass plantation.

    Science.gov (United States)

    Verlinden, M S; Fichot, R; Broeckx, L S; Vanholme, B; Boerjan, W; Ceulemans, R

    2015-01-01

    The efficiency of water use to produce biomass is a key trait in designing sustainable bioenergy-devoted systems. We characterized variations in the carbon isotope composition (δ(13) C) of leaves, current year wood and holocellulose (as proxies for water use efficiency, WUE) among six poplar genotypes in a short-rotation plantation. Values of δ(13) Cwood and δ(13) Cholocellulose were tightly and positively correlated, but the offset varied significantly among genotypes (0.79-1.01‰). Leaf phenology was strongly correlated with δ(13) C, and genotypes with a longer growing season showed a higher WUE. In contrast, traits related to growth and carbon uptake were poorly linked to δ(13) C. Trees growing on former pasture with higher N-availability displayed higher δ(13) C as compared with trees growing on former cropland. The positive relationships between δ(13) Cleaf and leaf N suggested that spatial variations in WUE over the plantation were mainly driven by an N-related effect on photosynthetic capacities. The very coherent genotype ranking obtained with δ(13) C in the different tree compartments has some practical outreach. Because WUE remains largely uncoupled from growth in poplar plantations, there is potential to identify genotypes with satisfactory growth and higher WUE. © 2014 John Wiley & Sons Ltd.

  3. Ovipositional preference and larval performance of poplar defoliator,Clostera restitura on different poplar clones in north-western India

    Institute of Scientific and Technical Information of China (English)

    Gurmail Singh; K.S. Sangha

    2012-01-01

    We evaluated ten poplar clones (G-3,G-48,L-50/88,L154/84,L-156/89,S7C8,S7C15.WSL-22,WSL-29 and Uday) for ovipositional preference and larval performance of Clostera restitura.Female moths did not show any preference with respect to clones for oviposition.Significant differences were observed for number of eggs laid on different plant parts.C.restitura laid eggs in clusters,preferably on upper surface of leaf and size of the egg cluster varied from 15 to 167 eggs.Clones varied for their relative resistance and susceptibility to C.restitura.L-50/88; L-156/89 were identified as most resistant clone based on minimum leaf consumption,whereas S7C15 was found to be most susceptible clone to C.restitura.In multiple choice experiments,no feeding preference by C restitura larvae was detected amongst different poplar clones.After initial settlement of larvae on a particular clone,the larvae remained confined to that clone and negligible inter-clonal movement was noticed subsequently.The fresh pupal weight was correlated negatively (r =-0.37) with percentage surface leaf area eaten and positively (r =0.47) with length of larval period,measured on different clones.Relationship between percentage leaf area eaten and length of larval period was negative (r =-0.23).Owing to relative resistance of L50/88 and L-156/89 against C.restitura,these clones can be recommended for plantation in defoliator prone areas in north-western India.

  4. Two-photon polymerization of 3-D zirconium oxide hybrid scaffolds for long-term stem cell growth.

    Science.gov (United States)

    Skoog, Shelby A; Nguyen, Alexander K; Kumar, Girish; Zheng, Jiwen; Goering, Peter L; Koroleva, Anastasia; Chichkov, Boris N; Narayan, Roger J

    2014-06-01

    Two-photon polymerization is a technique that involves simultaneous absorption of two photons from a femtosecond laser for selective polymerization of a photosensitive material. In this study, two-photon polymerization was used for layer-by-layer fabrication of 3-D scaffolds composed of an inorganic-organic zirconium oxide hybrid material. Four types of scaffold microarchitectures were created, which exhibit layers of parallel line features at various orientations as well as pores between the line features. Long-term cell culture studies involving human bone marrow stromal cells were conducted using these 3-D scaffolds. Cellular adhesion and proliferation were demonstrated on all of the scaffold types; tissuelike structure was shown to span the pores. This study indicates that two-photon polymerization may be used to create microstructured scaffolds out of an inorganic-organic zirconium oxide hybrid material for use in 3-D tissue culture systems.

  5. Effects of Nitrogen Fertilizer Level on Chlorophyll Fluorescence Characteristics in Flag Leaf of Super Hybrid Rice at Late Growth Stage

    Institute of Scientific and Technical Information of China (English)

    LONG Ji-rui; MA Guo-hui; WAN Yi-zheng; SONG Chun-fang; SUN Jian; QIN Rui-jun

    2013-01-01

    To compare the effects of slow-release nitrogen fertilizer at six different levels on the flag leaf chlorophyll fluorescence characteristics of super hybrid rice,a field fertilization experiment was conducted with super hybrid rice Y Liangyou 1 as a test material.The photosynthetic electron transport rate (ETR),effective quantum yield (EQY),photochemical quenching coefficient (qp),and non-photochemical quenching coefficient (NPQ) of flag leaves were measured at the initial heading,full heading,10 d after full heading and 20 d after full heading stages.Results showed that the values of ETR,EQY and qp increased with rice development from initial heading to 20 d after full heading,whereas the NPQ decreased.During the measured stages,ETR,EQY and qp increased initially and then decreased as nitrogen application amount increased,but they peaked at different nitrogen fertilizer levels.The maximum ETR and EQY values appeared at the treatment of 135 kg/hm2 N.In conclusion,the optimum nitrogen amount for chlorophyll fluorescence characteristics of super hybrid rice was 135-180 kg/hm2.

  6. Nutrient Dynamics of Fine Roots in the Mixed Plantation of Poplar and Black Locust

    Institute of Scientific and Technical Information of China (English)

    Zhai Mingpu; Jiang Sannai; Jia Liming

    2006-01-01

    The mixed plantation of poplar (Populus spp.)and black locust (Robinia pseudoacacia) is one of the typical mixed stands with nitrogen-fixing and non-nitrogen-fixing species.Interaction between the two species in the mixed stand is harmonious and productivity is high,making this kind of mixed plantation a very successful pattern on poor sandy sites in north China.In this study,the fine root decomposition of the two species was investigated in the mixed plantation of 27-year-old Canadian poplar (P.canadansis)and 22-year-old black locust on sandy sites along the Chaobai River in Beijing.Mechanism of harmonious interaction between the two species was observed in the view of the nutrient cycle of fine roots.Results showed that:(1) the fine root decomposition of Canadian poplar and black locust trees was different.Concentrations of N,Ca and Mg gradually increased and those of P and K gradually decreased in the fine roots of poplar during the period of decomposition.Concentrations of N,P and K gradually decreased in the fine roots of black locust during decomposition.The speed of nutrient decomposition in mixed fine roots of the two species fell between the speed of the two pure samples.(2) During decomposition,the annual return amount of N,K and Mg in fine roots of black locust was highest,followed by the mixed fine roots of the two species,and then the fine roots of poplar.(3) The increased return amount of N in mixed fine roots could improve the N nutrient condition of poplar trees.The return amount of P in poplar Fine roots was greater than that of black locust,which could improve the P nutrient of black locust trees.The interaction of mutual supplements of N and P nutrient cycle of fine roots between these two species formed.

  7. Effects of Water Deficit and Increased Nitrogen Application in the Late Growth Stage on Physiological Characters of Anti-aging of Leaves in Different Hybrid Rice Varieties

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] This study aimed to explore the effects of water and fertilizer regulation on the function of leaves in the filling stage. [Method] Six hybrid rice vari- eties including prematurely aged types and non-prematurely aged ones were selected as experimental materials. Limiting water treatment (with soil water potential of about -25 kpa) and increasing nitrogen treatment (additional 10% of granular nitrogen fertiliz- er in addition to limiting water treatment) were applied after heading to analyse the rates of aging and physiological responses of anti-aging in different hybrid rice vari- eties under water deficit and increased nitrogen conditions taking regular water and fertilizer as control. [Result] The results showed that water deficit accelerated the leaf senescence, and prematurely aged types-'Zhongyou838', 'Tianyou998' and 'Long- ping601 '-were more markedly affected by water deficit, of which the rates of chloro- phyll degradation were 6%-8% higher compared to that in another three hybrids. In- creasing nitrogen treatment raised chlorophyll content and slowed down its degrada- tion. Water deficit caused the increase of abscisic acid (ABA) content to obviously varying degrees in leaves of six hybried rice varieties. Responses of ABA content in six hybried rice varieties to increased nitrogen fertilizer were not consistent. Except in 'Zhongyou838', ABA content in the other five hybrids had varying degrees of in- crease. The responses of the activity of antioxidant enzymes in different hybried rice varieties were inconsistent. In response to increased nitrogen fertilizer in combination with water deficit, the activity of each antioxidant enzyme changed differently. Water deficit enhanced the accumulation of malondialdehyde (MDA) in leaves of each hybrid rice. The correlation analysis showed that chlorophyll content was extremely signifi- cantly positively correlated to the resistance of each antioxidant enzyme; SOD activity in leaves also positively

  8. Increased abundance of insulin/insulin-like growth factor-I hybrid receptors in skeletal muscle of obese subjects is correlated with in vivo insulin sensitivity.

    Science.gov (United States)

    Federici, M; Porzio, O; Lauro, D; Borboni, P; Giovannone, B; Zucaro, L; Hribal, M L; Sesti, G

    1998-08-01

    We reported that in noninsulin-dependent diabetes melitus (NIDDM) patients expression of insulin/insulin-like growth factor I (IGF-I) hybrid receptors is increased in insulin target tissues. Whether this is a defect associated with NIDDM or represents a generalized abnormality associated with insulin resistant states is still unsettled. To address this, we applied a microwell-based immunoassay to measure abundance of insulin receptors, type 1 IGF receptors, and hybrid receptors in muscle of eight normal and eight obese subjects. Maximal insulin binding to insulin receptors was lower in obese than in control subjects (B/T = 1.8 +/- 0.20 and 2.6 +/- 0.30; P < 0.03, respectively) and was negatively correlated with insulinemia (r = -0.60; P < 0.01). Maximal IGF-I binding to type 1 IGF receptors was higher in obese than in controls (B/T = 1.9 +/- 0.20 and 0.86 +/- 0.10; P < 0.0001, respectively) and was negatively correlated with plasma IGF-I levels (r = -0.69; P < 0.003). Hybrid receptor abundance was higher in obese than in normal subjects (B/T = 1.21 +/- 0.14 and 0.44 +/- 0.06; P < 0.0003, respectively) and was negatively correlated with insulin binding (r = -0.60; P < 0.01) and positively correlated with IGF-I binding (r = 0.92; P < 0.0001). Increased abundance of hybrids was correlated with insulinemia (r = 0.70; P < 0.002) and body mass index (r = 0.71; P < 0.0019), whereas it was negatively correlated with in vivo insulin sensitivity measured by ITT (r = -0.67; P < 0.016). These results indicate that downregulation of insulin receptors or upregulation of type 1 IGF receptors because of changes in plasma insulin and IGF-I levels may result in modifications in hybrid receptor abundance.

  9. COMPARISON OF APMP PULP CHARACTERISTICS OF JUVENILE TRIPLOID CHINESE WHITE POPLAR IN SALINE SOIL WITH THAT OF NORMAL 5-YEAR POPLAR

    Institute of Scientific and Technical Information of China (English)

    Hongchun Zou; Guomin Tan; Qun Li; Zimin Zhang

    2004-01-01

    In the paper, differences between the juvenile Triploid Chinese White Poplar TCWP in saline soil and 5-year TCWP in normal soil are compared in terms of their APMP-pulping properties. The results show that the saline planting environment does not show obvious effects on pulping properties of juvenile TCWP.

  10. Identification of growth phenotype-related genes in Aspergillus oryzae by heterologous macroarray and suppression subtractive hybridization

    NARCIS (Netherlands)

    Biesebeke, R. te; Levin, A.; Sagt, C.; Bartels, J.; Goosen, T.; Ram, A.; Hondel, C. van den; Punt, P.

    2005-01-01

    Aspergillus oryzae requires polarized growth for colonization of solid substrates, and this growth phenotype differs from that seen in liquid medium. Various experimental approaches were used to identify genes that are differentially expressed when A. oryzae is grown on wheat kernels and in a wheat-

  11. Identification of growth phenotype-related genes in Aspergillus oryzae by heterologous macroarray and suppression subtractive hybridization

    NARCIS (Netherlands)

    Biesebeke, R. te; Levin, A.; Sagt, C.; Bartels, J.; Goosen, T.; Ram, A.; Hondel, C. van den; Punt, P.

    2005-01-01

    Aspergillus oryzae requires polarized growth for colonization of solid substrates, and this growth phenotype differs from that seen in liquid medium. Various experimental approaches were used to identify genes that are differentially expressed when A. oryzae is grown on wheat kernels and in a wheat-

  12. Identification of growth phenotype-related genes in Aspergillus oryzae by heterologous macroarray and suppression subtractive hybridization

    NARCIS (Netherlands)

    Biesebeke, R. te; Levin, A.; Sagt, C.; Bartels, J.; Goosen, T.; Ram, A.; Hondel, C. van den; Punt, P.

    2005-01-01

    Aspergillus oryzae requires polarized growth for colonization of solid substrates, and this growth phenotype differs from that seen in liquid medium. Various experimental approaches were used to identify genes that are differentially expressed when A. oryzae is grown on wheat kernels and in a

  13. Evaluation of Bioenergy Crop Growth and the Impacts Of Bioenergy Crops on Streamflow, Tile Drain Flow and Nutrient Losses Using SWAT

    Science.gov (United States)

    Guo, T.; Raj, C.; Chaubey, I.; Gitau, M. W.; Arnold, J. G.; Srinivasan, R.; Kiniry, J. R.; Engel, B.

    2016-12-01

    Bioenery crops are expected to produce large quantities of biofuel at a national scale to meet US biofuel goals. It is important to study bioenergy crop growth and the impacts on water quantity and quality to identify environment-friendly and productive biofeedstocks. In this study, SWAT2012 with a new tile drainage routine (DRAINMOD routine) and improved perennial grass and tree growth simulation was used to model long-term annual biomass yields, streamflow, tile flow, sediment load, total nitrogen, nitrate load in flow, nitrate in tile flow, soluble nitrogen, organic nitrogen, total phosphorus, mineral phosphorus and organic phosphorus under various bioenergy scenarios in an extensively agricultural watershed in the Midwestern US. The results showed that simulated annual crop yields matched with observed county level values for corn and soybeans, and were reasonable for Miscanthus, switchgrass and hybrid poplar. Removal of 38% of corn stover (66,439 Mg/yr) with Miscanthus production on highly erodible areas and marginal land (19,039 Mg/yr) provided the highest biofeedstock production. Streamflow, tile flow, erosion and nutrient losses were reduced under bioenergy crop scenarios of Miscanthus, switchgrass, and hybrid poplar on highly erodible areas, marginal land. Corn stover removal did not result in significant water quality changes. The increase in sediment load and nutrient losses under corn stover removal could be offset with production of other bioenergy crops. The study showed that corn stover removal with bioenergy crops both on highly erodible areas and marginal land could provide more biofuel production relative to the baseline, and was beneficial to hydrology and water quality at the watershed scale, providing guidance for further research on evaluation of bioenergy crop scenarios in a typical extensively tile-drained watershed in the Midwestern U.S.

  14. Dissecting nutrient-related co-expression networks in phosphate starved poplars

    Science.gov (United States)

    Kavka, Mareike; Polle, Andrea

    2017-01-01

    Phosphorus (P) is an essential plant nutrient, but its availability is often limited in soil. Here, we studied changes in the transcriptome and in nutrient element concentrations in leaves and roots of poplars (Populus × canescens) in response to P deficiency. P starvation resulted in decreased concentrations of S and major cations (K, Mg, Ca), in increased concentrations of N, Zn and Al, while C, Fe and Mn were only little affected. In roots and leaves >4,000 and >9,000 genes were differently expressed upon P starvation. These genes clustered in eleven co-expression modules of which seven were correlated with distinct elements in the plant tissues. One module (4.7% of all differentially expressed genes) was strongly correlated with changes in the P concentration in the plant. In this module the GO term “response to P starvation” was enriched with phosphoenolpyruvate carboxylase kinases, phosphatases and pyrophosphatases as well as regulatory domains such as SPX, but no phosphate transporters. The P-related module was also enriched in genes of the functional category “galactolipid synthesis”. Galactolipids substitute phospholipids in membranes under P limitation. Two modules, one correlated with C and N and the other with biomass, S and Mg, were connected with the P-related module by co-expression. In these modules GO terms indicating “DNA modification” and “cell division” as well as “defense” and “RNA modification” and “signaling” were enriched; they contained phosphate transporters. Bark storage proteins were among the most strongly upregulated genes in the growth-related module suggesting that N, which could not be used for growth, accumulated in typical storage compounds. In conclusion, weighted gene coexpression network analysis revealed a hierarchical structure of gene clusters, which separated phosphate starvation responses correlated with P tissue concentrations from other gene modules, which most likely represented

  15. Production potential of 36 poplar clones grown at medium length rotation in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Ulrik Brauner; Madsen, Palle; Hansen, Jon Kehlet

    2014-01-01

    group's potential for use in Northern Europe and comparable growth conditions. Based on two trials with randomized block designs, 36 clones from 4 species and 5 groups of species hybrids, measurements of height and diameter were used for estimating biomass production for rotation lengths of 5 and 13...

  16. Hybridization and extinction.

    Science.gov (United States)

    Todesco, Marco; Pascual, Mariana A; Owens, Gregory L; Ostevik, Katherine L; Moyers, Brook T; Hübner, Sariel; Heredia, Sylvia M; Hahn, Min A; Caseys, Celine; Bock, Dan G; Rieseberg, Loren H

    2016-08-01

    Hybridization may drive rare taxa to extinction through genetic swamping, where the rare form is replaced by hybrids, or by demographic swamping, where population growth rates are reduced due to the wasteful production of maladaptive hybrids. Conversely, hybridization may rescue the viability of small, inbred populations. Understanding the factors that contribute to destructive versus constructive outcomes of hybridization is key to managing conservation concerns. Here, we survey the literature for studies of hybridization and extinction to identify the ecological, evolutionary, and genetic factors that critically affect extinction risk through hybridization. We find that while extinction risk is highly situation dependent, genetic swamping is much more frequent than demographic swamping. In addition, human involvement is associated with increased risk and high reproductive isolation with reduced risk. Although climate change is predicted to increase the risk of hybridization-induced extinction, we find little empirical support for this prediction. Similarly, theoretical and experimental studies imply that genetic rescue through hybridization may be equally or more probable than demographic swamping, but our literature survey failed to support this claim. We conclude that halting the introduction of hybridization-prone exotics and restoring mature and diverse habitats that are resistant to hybrid establishment should be management priorities.

  17. Impacts of transgenic poplar-cotton agro-ecosystems upon target pests and non-target insects under field conditions.

    Science.gov (United States)

    Zhang, D J; Liu, J X; Lu, Z Y; Li, C L; Comada, E; Yang, M S

    2015-07-27

    Poplar-cotton agro-ecosystems are the main agricultural planting modes of cotton fields in China. With increasing acres devoted to transgenic insect-resistant poplar and transgenic insect-resistant cotton, studies examining the effects of transgenic plants on target and non-target insects become increasingly important. We systematically surveyed populations of both target pests and non-target insects for 4 different combinations of poplar-cotton eco-systems over 3 years. Transgenic Bt cotton strongly resisted the target insects Fall webworm moth [Hyphantria cunea (Drury)], Sylepta derogata Fabrieius, and American bollworm (Heliothis armigera), but no clear impact on non-target insect cotton aphids (Aphis gossypii). Importantly, intercrops containing transgenic Pb29 poplar significantly increased the inhibitory effects of Bt cotton on Fall webworm moth in ecosystem IV. Highly resistant Pb29 poplar reduced populations of the target pests Grnsonoma minutara Hubner and non-target insect poplar leaf aphid (Chaitophorus po-pulialbae), while Fall webworm moth populations were unaffected. We determined the effects of Bt toxin from transgenic poplar and cotton on target and non-target pests in different ecosystems of cotton-poplar intercrops and identified the synergistic effects of such combinations toward both target and non-target insects.

  18. Fertilization effects on biomass production, nutrient leaching and budgets in four stand development stages of short rotation forest poplar

    DEFF Research Database (Denm