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Michel Labrecque - One of the best experts on this subject based on the ideXlab platform.
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Willows for the treatment of municipal wastewater performance under different irrigation rates
Ecological Engineering, 2015Co-Authors: Werther Guidi Nissim, Ahmed Jerbi, Benoit Lafleur, Remy Fluet, Michel LabrecqueAbstract:Abstract Willow cropping is increasingly spreading worldwide for various purposes including vegetation filter. Willow plantations are highly nutrient-demanding and site fertilization may be required to maintain soil fertility and nutrient balance. In this context, municipal wastewater could be a valuable source of nutrients (especially N and P) and water for plant growth. The aim of this study was to assess the performance of Willows to recycle municipal wastewater supplied at different rates. In particular, we sought to evaluate the quality of groundwater water collected under Willow and assess the effect of wastewater supply on Willow growth. Irrigation with wastewater had a positive effect on Willow growth and biomass yield. It was also estimated that Willows were able to remove nearly 90% of the N and 85% of the P found in the wastewater. This study shows that a Willow vegetation filter is very efficient at removing nutrients found in wastewater.
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phylogenetic relationships of american Willows salix l salicaceae
PLOS ONE, 2015Co-Authors: Aurelien Lauronmoreau, Frederic E Pitre, Michel Labrecque, George W Argus, Luc BrouilletAbstract:Salix L. is the largest genus in the family Salicaceae (450 species). Several classifications have been published, but taxonomic subdivision has been under continuous revision. Our goal is to establish the phylogenetic structure of the genus using molecular data on all American Willows, using three DNA markers. This complete phylogeny of American Willows allows us to propose a biogeographic framework for the evolution of the genus. Material was obtained for the 122 native and introduced Willow species of America. Sequences were obtained from the ITS (ribosomal nuclear DNA) and two plastid regions, matK and rbcL. Phylogenetic analyses (parsimony, maximum likelihood, Bayesian inference) were performed on the data. Geographic distribution was mapped onto the tree. The species tree provides strong support for a division of the genus into two subgenera, Salix and Vetrix. Subgenus Salix comprises temperate species from the Americas and Asia, and their disjunction may result from Tertiary events. Subgenus Vetrix is composed of boreo-arctic species of the Northern Hemisphere and their radiation may coincide with the Quaternary glaciations. Sixteen species have ambiguous positions; genetic diversity is lower in subg. Vetrix. A molecular phylogeny of all species of American Willows has been inferred. It needs to be tested and further resolved using other molecular data. Nonetheless, the genus clearly has two clades that have distinct biogeographic patterns.
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high biomass yield achieved by salix clones in sric following two 3 year coppice rotations on abandoned farmland in southern quebec canada
Biomass & Bioenergy, 2003Co-Authors: Michel Labrecque, Traian I TeodorescuAbstract:Abstract Two species of Willow, Salix discolor and S. viminalis , were planted in 1995 under short-rotation intensive culture on two abandoned farmland sites: sandy site (S1) and clay site (S2). After three seasons of growth the two species were coppiced. In the spring of the first season following coppicing, one dose of composted sludge equivalent to 100 kg of “available” N ha −1 was applied to some plots (T1) while others were left unfertilized (T0). The aims of the experiment were to compare the growth performance and nutrients exported by Willow species planted on marginal sites with different soil characteristics and to assess the impact of fertilization with wastewater sludge on yields during a second rotation cycle. Over three seasons, Willow height, diameter and aboveground biomass were greater for S. viminalis than for S. discolor on all fertilized plots. The best growth performance of two Willows were obtained on the clay site. S. viminalis , planted on the fertilized plots of the clay site, had the highest biomass yield (70.36 tDM ha −1 ) . The application of a dose of wastewater sludge ( 100 kg of “available” N ha −1 ) was not enough to satisfy all nutritional requirements of Willows for the period of growth. Over the second rotation the nutrients removed from the soil by Willows (in kg per ton of dry mass harvested) were: from 5.3 to 7.5 for N; from 0.6 to 0.9 for P; from 1.8 to 3 for K; from 4.2 to 7.2 for Ca and from 0.4 to 0.7 for Mg.
M H Pei - One of the best experts on this subject based on the ideXlab platform.
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genetic improvement of Willow for bioenergy and biofuels
Journal of Integrative Plant Biology, 2011Co-Authors: A. Karp, M H Pei, Steve Hanley, Sviatlana O Trybush, W J Macalpine, I ShieldAbstract:Willows (Salix spp.) are a very diverse group of catkin-bearing trees and shrubs that are widely distributed across temperate regions of the globe. Some species respond well to being grown in short rotation coppice (SRC) cycles, which are much shorter than conventional forestry. Coppicing reinvigorates growth and the biomass rapidly accumulated can be used as a source of renewable carbon for bioenergy and biofuels. As SRC Willows re-distribute nutrients during the perennial cycle they require only minimal nitrogen fertilizer for growth. This results in fuel chains with potentially high greenhouse gas reductions. To exploit their potential for renewable energy, Willows need to be kept free of pests and diseases and yields need to be improved without significantly increasing the requirements for fertilizers and water. The biomass composition needs to be optimized for different end-uses. Yields also need to be sustainable on land less productive for food crops to reduce conflicts over land use. Advances in understanding the physiology and growth of Willow, and in the identification of genes underlying key traits, are now at the stage where they can start to be used in breeding programs to help achieve these goals.
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interactions between melamspora larici epitea pathotypes and the mycoparasite sphaerellopsis filum from Willow rusts
Forest Pathology, 2010Co-Authors: M H Pei, C Ruiz, T Hunter, C BayonAbstract:Summary Five pathotypes of the Willow rust Melamspora larici-epitea were inoculated with 12 isolates of Sphaerellopsis filum derived from Melampsora species/forms occurring on Willows. On average, 20.5% uredinial pustules produced S. filum pycnidia and rust spore production was reduced by 38.4% on leaf discs inoculated with S. filum. Some rust isolates were more readily infected by S. filum than others while some S. filum isolates caused higher levels of infections than other S. filum isolates. In general, the suppressive effects of these S. filum isolates on rust spore production were similar on the majority of rust pathotypes tested. There appeared to be a positive link between the rust pustule area and the rate of infection by S. filum. Sphaerellopsis filum inoculum densities were positively correlated with the reduction in rust spore production but not with the number of rust pustules. Implications from the results were discussed in relation to the deployment of S. filum in biological control of Willow rust in Willow mixture plantations which harbour more diverse rust pathotypes compared with monocultures.
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occurrence of melampsora rusts in biomass Willow plantations for renewable energy in the united kingdom
Biomass & Bioenergy, 1999Co-Authors: M H Pei, T Hunter, C RuizAbstract:The natural occurrence of Melampsora rusts in biomass Willow plantations for renewable energy was investigated at four sites in the UK during 1992–1994. Three sites, located at Long Ashton, south west England, Loughgall, Northern Ireland, and Craibstone, Scotland, were rust/clone trials that contained standard 24 Willow clones and the fourth site at Markington, northern England, had a similar range of Willows. Larch-alternating M. epitea (M. larici-epitea) was found to be most prevalent. Melampsora capraearum was predominant on S. caprea hybrids and the stem-infecting form occurred mainly on S. viminalis ‘Bowles Hybrid’. To identify different pathotypes in larch-alternating M. epitea, field rust samples were tested for pathogenicity in the laboratory using eight Willow differentials. A total of 12 pathotypes were identified. More pathotypes were found at Long Ashton, Loughgall and Markington, where extensive, long-term Willow plantings were grown, than at Craibstone, where the planting was more isolated. A major breakdown of rust resistance in S. ×mollissima ‘Q83’ in the UK in 1992 was caused by the emergence of a new pathotype. Our results also suggest that the larch-alternating M. epitea found in UK biomass Willow plantations may consist of genetically separate populations. This would provide an opportunity to plant Willow clones that harbour different mating populations, in mixed plantations in order to enhance the property of mixtures to suppress rust.
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identity and host alternation of some Willow rusts melampsora spp in england
Fungal Biology, 1993Co-Authors: M H Pei, D J Royle, T HunterAbstract:Six species of Melampsora: M. salicis-albae, M. larici-pentandrae, M. amygdalinae, M. capraearum, M. ribesii-viminalis and M. epitea , were identified among 26 Willow leaf samples collected mainly in SW England. Identification of species was based on the morphology of the uredinial and telial stages as well as on the results of inoculations of the aecial hosts. M. epitea occurred alone in 18 leaf samples, and together with M. ribesii-viminalis in one further sample. Basidiospores produced from teliospores of the autoecious M. amygdalinae infected Salix triandra (a species of tree Willows). All other species were heteroecious, with M. larici-pentandrae, M. capraearum and M. epitea producing spermogonia and aecia on Larix decidua (European larch), and less readily on L. kaempferi (Japanese larch). M. ribesii-viminalis and a form of M. epitea from S. purpurea , occasionally formed spermogonia but not aecia on Ribes spp. M. epitea, M. capraearum , and M. ribesii-viminalis occurred on cultivars of shrub Willows which are favoured for short-rotation, coppiced energy cropping in the U.K.
A. Karp - One of the best experts on this subject based on the ideXlab platform.
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g fibre cell wall development in Willow stems during tension wood induction
Journal of Experimental Botany, 2015Co-Authors: C Gritsch, Steven J Hanley, R A C Mitchell, Peter R Shewry, A. KarpAbstract:Willows (Salix spp.) are important as a potential feedstock for bioenergy and biofuels. Previous work suggested that reaction wood (RW) formation could be a desirable trait for biofuel production in Willows as it is associated with increased glucose yields, but Willow RW has not been characterized for cell wall components. Fasciclin-like arabinogalactan (FLA) proteins are highly up-regulated in RW of poplars and are considered to be involved in cell adhesion and cellulose biosynthesis. COBRA genes are involved in anisotropic cell expansion by modulating the orientation of cellulose microfibril deposition. This study determined the temporal and spatial deposition of non-cellulosic polysaccharides in cell walls of the tension wood (TW) component of Willow RW and compared it with opposite wood (OW) and normal wood (NW) using specific antibodies and confocal laser scanning microscopy and transmission electron microscopy. In addition, the expression patterns of an FLA gene (SxFLA12) and a COBRA-like gene (SxCOBL4) were compared using RNA in situ hybridization. Deposition of the non-cellulosic polysaccharides (1–4)-β-D-galactan, mannan and de-esterified homogalacturonan was found to be highly associated with TW, often with the G-layer itself. Of particular interest was that the G-layer itself can be highly enriched in (1–4)-β-D-galactan, especially in G-fibres where the G-layer is still thickening, which contrasts with previous studies in poplar. Only xylan showed a similar distribution in TW, OW, and NW, being restricted to the secondary cell wall layers. SxFLA12 and SxCOBL4 transcripts were specifically expressed in developing TW, confirming their importance. A model of polysaccharides distribution in developing Willow G-fibre cells is presented.
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functional screening of Willow alleles in arabidopsis combined with qtl mapping in Willow salix identifies sxmax4 as a coppicing response gene
Plant Biotechnology Journal, 2014Co-Authors: Jemma Salmon, Sally Ward, Steven J Hanley, Ottoline Leyser, A. KarpAbstract:Willows (Salix spp.) are important biomass crops due to their ability to grow rapidly with low fertilizer inputs and ease of cultivation in short-rotation coppice cycles. They are relatively undomesticated and highly diverse, but functional testing to identify useful allelic variation is time-consuming in trees and transformation is not yet possible in Willow. Arabidopsis is heralded as a model plant from which knowledge can be transferred to advance the improvement of less tractable species. Here, knowledge and methodologies from Arabidopsis were successfully used to identify a gene influencing stem number in coppiced Willows, a complex trait of key biological and industrial relevance. The strigolactone-related More AXillary growth (MAX) genes were considered candidates due to their role in shoot branching. We previously demonstrated that Willow and Arabidopsis show similar response to strigolactone and that transformation rescue of Arabidopsis max mutants with Willow genes could be used to detect allelic differences. Here, this approach was used to screen 45 SxMAX1, SxMAX2, SxMAX3 and SxMAX4 alleles cloned from 15 parents of 11 mapping populations varying in shoot-branching traits. Single-nucleotide polymorphism (SNP) frequencies were locus dependent, ranging from 29.2 to 74.3 polymorphic sites per kb. SxMAX alleles were 98%-99% conserved at the amino acid level, but different protein products varying in their ability to rescue Arabidopsis max mutants were identified. One poor rescuing allele, SxMAX4D, segregated in a Willow mapping population where its presence was associated with increased shoot resprouting after coppicing and colocated with a QTL for this trait.
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genetic improvement of Willow for bioenergy and biofuels
Journal of Integrative Plant Biology, 2011Co-Authors: A. Karp, M H Pei, Steve Hanley, Sviatlana O Trybush, W J Macalpine, I ShieldAbstract:Willows (Salix spp.) are a very diverse group of catkin-bearing trees and shrubs that are widely distributed across temperate regions of the globe. Some species respond well to being grown in short rotation coppice (SRC) cycles, which are much shorter than conventional forestry. Coppicing reinvigorates growth and the biomass rapidly accumulated can be used as a source of renewable carbon for bioenergy and biofuels. As SRC Willows re-distribute nutrients during the perennial cycle they require only minimal nitrogen fertilizer for growth. This results in fuel chains with potentially high greenhouse gas reductions. To exploit their potential for renewable energy, Willows need to be kept free of pests and diseases and yields need to be improved without significantly increasing the requirements for fertilizers and water. The biomass composition needs to be optimized for different end-uses. Yields also need to be sustainable on land less productive for food crops to reduce conflicts over land use. Advances in understanding the physiology and growth of Willow, and in the identification of genes underlying key traits, are now at the stage where they can start to be used in breeding programs to help achieve these goals.
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estimating root biomass in salix viminalis salix schwerinii cultivar olof using the electrical capacitance method
Plant Biosystems, 2010Co-Authors: Frederic E Pitre, Nicholas J B Brereton, S Audoire, G M Richter, I Shield, A. KarpAbstract:Abstract Non‐destructive assessment of root systems is important in order to understand and optimise the potential of resource capture and allocation by the plant. We studied the relationships between electrical capacitance (EC) and the below‐ and above‐ground biomass of Willows. Cuttings of Salix viminalis × Salix schwerinii cv. Olof were maintained in pots and root development was followed up using a portable capacitance meter over the course of 2.5 months. Pot observations were compared with excavation of two‐year‐old established trees. A strong significant linear relationship (R 2 = 0.81, p < 0.001) was obtained between EC and root biomass (dry weight [DW]) for the pot experiment. EC also showed good correlations with stem and leaf biomass, as well as with stem height. In the excavated Willow trees, there was a strong logarithmic relationship between EC and root biomass (R 2 = 0.66, p < 0.001). These results suggest that EC is a good estimator of below‐ground biomass in Willow and may become useful in...
Timothy A Volk - One of the best experts on this subject based on the ideXlab platform.
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Hot Water Extraction Improves the Characteristics of Willow and Sugar Maple Biomass With Different Amount of Bark
Frontiers Media S.A., 2018Co-Authors: Obste Therasme, Timothy A Volk, Mark H. Eisenbies, Antonio M. Cabrera, Thomas E. AmidonAbstract:Shrub Willows are being developed as a short rotation woody crop (SRWC) that can grow on marginal agricultural land. Willow has a high net energy ratio (energy produced/ fossil fuel energy consumed), low greenhouse gas footprint and high carbohydrate production potential. Willow biomass can be combined with forest biomass, but Willow often has a higher proportion of bark that creates challenges because it increases the ash content and decreases the melting point. Hot water extraction is a pretreatment that has been shown to improve the quality of chipped material while producing a marketable stream of byproducts. This study evaluated how the amount of bark (0, 33, 66, and 100%) on three Willow cultivars and sugar maple impact the output of hot water extraction in terms of mass removal and extract composition, as well as its influence on the heating value, ash and elemental content. The hot water extraction process resulted in ash content up to 50% for sugar maple and Willow, but there was variation among the Willow varieties. The heating value after hot water extraction was about 5% higher because of the removal of mostly hemicelluloses, which have relatively low heating value. HWE led to significant reductions of calcium, potassium, magnesium and sulfur contents. The hot water extraction provides a fermentable sugar stream and other coproducts after multiple separation and treatment steps, and improves the characteristics of Willow and sugar maple biomass for combined heat and power. This paper demonstrates how biomass with higher bark content can generate a useable sugar stream while improving the quality of the biomass for combined heat and power by managing its ash content while simultaneously producing other valuable products
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the characterization of Willow salix l varieties for use in ecological engineering applications co ordination of structure function and autecology
Ecological Engineering, 2009Co-Authors: Yulia A Kuzovkina, Timothy A VolkAbstract:Abstract The rapid development of innovative and highly specialized ecotechnologies targeting site-specific problems and pollutants requires precisely tailored designs. The proper selection of remedial plant genotypes that possess the correct structure and function to effectively address a specific problem is a vital step in the design of ecological engineering applications because numerous essential traits must be evaluated to maximize the effectiveness of each installation. Knowledge about the biology of Willow species from decades of research as a perennial biomass crop has recently been applied to resolving an array of environmental and ecological problems. Here, essential characteristics of Salix varieties that are pertinent to ecological engineering are described and related to particular ecotechnologies. We identified thirty-six agronomical, physiological, and ecological attributes of Willow that provide a framework for species selection and assist in the identification of site-specific functional types of Willows for land reclamation, phytoremediation, bioengineering, and agroforestry.
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renewable energy from Willow biomass crops life cycle energy environmental and economic performance
Critical Reviews in Plant Sciences, 2005Co-Authors: Gregory A Keoleian, Timothy A VolkAbstract:Short-rotation woody crops (SRWC) along with other woody biomass feedstocks will play a significant role in a more secure and sustainable energy future for the United States and around the world. In temperate regions, shrub Willows are being developed as a SRWC because of their potential for high biomass production in short time periods, ease of vegetative propagation, broad genetic base, and ability to resprout after multiple harvests. Understanding and working with Willow's biology is important for the agricultural and economic success of the system. The energy, environmental, and economic performance of Willow biomass production and conversion to electricity is evaluated using life cycle modeling methods. The net energy ratio (electricity generated/life cycle fossil fuel consumed) for Willow ranges from 10 to 13 for direct firing and gasification processes. Reductions of 70 to 98 percent (compared to U.S. grid generated electricity) in greenhouse gas emissions as well as NOx, SO2, and particulate emiss...
T Hunter - One of the best experts on this subject based on the ideXlab platform.
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interactions between melamspora larici epitea pathotypes and the mycoparasite sphaerellopsis filum from Willow rusts
Forest Pathology, 2010Co-Authors: M H Pei, C Ruiz, T Hunter, C BayonAbstract:Summary Five pathotypes of the Willow rust Melamspora larici-epitea were inoculated with 12 isolates of Sphaerellopsis filum derived from Melampsora species/forms occurring on Willows. On average, 20.5% uredinial pustules produced S. filum pycnidia and rust spore production was reduced by 38.4% on leaf discs inoculated with S. filum. Some rust isolates were more readily infected by S. filum than others while some S. filum isolates caused higher levels of infections than other S. filum isolates. In general, the suppressive effects of these S. filum isolates on rust spore production were similar on the majority of rust pathotypes tested. There appeared to be a positive link between the rust pustule area and the rate of infection by S. filum. Sphaerellopsis filum inoculum densities were positively correlated with the reduction in rust spore production but not with the number of rust pustules. Implications from the results were discussed in relation to the deployment of S. filum in biological control of Willow rust in Willow mixture plantations which harbour more diverse rust pathotypes compared with monocultures.
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occurrence of melampsora rusts in biomass Willow plantations for renewable energy in the united kingdom
Biomass & Bioenergy, 1999Co-Authors: M H Pei, T Hunter, C RuizAbstract:The natural occurrence of Melampsora rusts in biomass Willow plantations for renewable energy was investigated at four sites in the UK during 1992–1994. Three sites, located at Long Ashton, south west England, Loughgall, Northern Ireland, and Craibstone, Scotland, were rust/clone trials that contained standard 24 Willow clones and the fourth site at Markington, northern England, had a similar range of Willows. Larch-alternating M. epitea (M. larici-epitea) was found to be most prevalent. Melampsora capraearum was predominant on S. caprea hybrids and the stem-infecting form occurred mainly on S. viminalis ‘Bowles Hybrid’. To identify different pathotypes in larch-alternating M. epitea, field rust samples were tested for pathogenicity in the laboratory using eight Willow differentials. A total of 12 pathotypes were identified. More pathotypes were found at Long Ashton, Loughgall and Markington, where extensive, long-term Willow plantings were grown, than at Craibstone, where the planting was more isolated. A major breakdown of rust resistance in S. ×mollissima ‘Q83’ in the UK in 1992 was caused by the emergence of a new pathotype. Our results also suggest that the larch-alternating M. epitea found in UK biomass Willow plantations may consist of genetically separate populations. This would provide an opportunity to plant Willow clones that harbour different mating populations, in mixed plantations in order to enhance the property of mixtures to suppress rust.
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identity and host alternation of some Willow rusts melampsora spp in england
Fungal Biology, 1993Co-Authors: M H Pei, D J Royle, T HunterAbstract:Six species of Melampsora: M. salicis-albae, M. larici-pentandrae, M. amygdalinae, M. capraearum, M. ribesii-viminalis and M. epitea , were identified among 26 Willow leaf samples collected mainly in SW England. Identification of species was based on the morphology of the uredinial and telial stages as well as on the results of inoculations of the aecial hosts. M. epitea occurred alone in 18 leaf samples, and together with M. ribesii-viminalis in one further sample. Basidiospores produced from teliospores of the autoecious M. amygdalinae infected Salix triandra (a species of tree Willows). All other species were heteroecious, with M. larici-pentandrae, M. capraearum and M. epitea producing spermogonia and aecia on Larix decidua (European larch), and less readily on L. kaempferi (Japanese larch). M. ribesii-viminalis and a form of M. epitea from S. purpurea , occasionally formed spermogonia but not aecia on Ribes spp. M. epitea, M. capraearum , and M. ribesii-viminalis occurred on cultivars of shrub Willows which are favoured for short-rotation, coppiced energy cropping in the U.K.
