为探明荒漠植物沙柳（Salix psammophila）根围AM真菌时空异质性,2009年5月、8月和10月分别从内蒙古荒漠植物沙柳根围分0~10,11~20,21~30,31~40和41~50 cm 5个土层采集土壤样品,研究了AM真菌时空分布及与土壤因子的相关性.结果表明,沙...为探明荒漠植物沙柳（Salix psammophila）根围AM真菌时空异质性,2009年5月、8月和10月分别从内蒙古荒漠植物沙柳根围分0~10,11~20,21~30,31~40和41~50 cm 5个土层采集土壤样品,研究了AM真菌时空分布及与土壤因子的相关性.结果表明,沙柳根围AM真菌平均孢子密度为282个/100g,平均总定殖率0.642;从土壤中共分离AM真菌3属20种,其中球囊霉属（Glomus）15种、无梗囊霉属（Acaulospora）4种、盾巨孢囊霉属（Scutellospora）1种.AM真菌孢子密度、菌丝定殖率和丛枝定殖率随时间变化先升后降,最大值出现在8月;泡囊定殖率随时间变化先降后升,最大值出现在10月;随土壤深度增加,孢子密度和定殖率下降,最大孢子密度和最高定殖率均出现在10月份0~10 cm土层.孢子密度与土壤温度、pH极显著正相关,与土壤速效P极显著负相关;泡囊定殖率与土壤碱解N显著正相关;丛枝定殖率与土壤温度、湿度和pH极显著正相关,与土壤碱解N极显著负相关;菌丝定殖率与易提取球囊霉素极显著正相关.总球囊霉素和易提取球囊霉素与土壤碱解N和有机C极显著正相关.球囊霉素含量的动态变化能够综合反映土壤AM真菌分布和活动、有机C动态和养分循环进程,应作为荒漠土壤质量和功能评价的新指标进一步深入研究.展开更多
An in vitro gas production （GP） technique was used to investigate the effects of combining different doses of Salix babylonica extract （SB） with exogenous fibrolytic enzymes （EZ） based on xylanase （X） and cell...An in vitro gas production （GP） technique was used to investigate the effects of combining different doses of Salix babylonica extract （SB） with exogenous fibrolytic enzymes （EZ） based on xylanase （X） and cellulase （C）, or their mixture （XC; 1：1 v/v） on in vitro fermentation characteristics of a total mixed ration of corn silage and concentrate mixture （50：50, w/w） as substrate. Four levels of SB （0, 0.6, 1.2 and 1.8 mL g-1 dry matter （DM）） and four supplemental styles of EZ （1 μL g-1 DM; control （no enzymes）, X, C and XC （1：1, v/v） were used in a 4×4 factorial arrangement. In vitro GP （mL g-1 DM） were recorded at 2, 4, 6, 8, 10, 12, 24, 36, 48 and 72 h of incubation. After 72 h, the incubation process was stopped and supernatant pH was determined, and then filtered to determine dry matter degradability （DMD）. Fermentation parameters, such as the 24 h gas yield （GY24）, in vitro organic matter digestibility （OMD）, metabolizable energy （ME）, short chain fatty acid concentrations （SCFA）, and microbial crude protein production （MCP） were also estimated. Results indicated that there was a SBxEZ interaction （P〈0.0001） for the asymptotic gas production （b）, the rate of gas production （c）, GP from 6 to 72 h, GP2 （P=0.0095）, and GP4 （P=0.02）. The SB and different combination of enzymes supplementation influenced （P〈0.001） in vitro GP parameters after 12 h of incubation; the highest doses of SB （i.e., 1.8 mL g-1 DM）, in the absence of any EZ, quadratically increased （P〈0.05） the initial delay before GP begins （L） and GP at different incubation times, with lowering b （quadratic effect, P〈0.0001 ） and c （quadratic effect, P〈0.0001 ; linear effect, P=0.0018）. The GP was the lowest （P〈0.05） when the highest SB level was combined with cellulose. There were SBxEZ interactions （P〈0.001） for OMD, ME, the partitioning factor at 72 h of incubation （PF72）, GY24, SCFA, MCP （P=0.0143）, and pH （P=0.0008）. The OMD, ME, GY24 and SCFA with supplementation of SB extract at 1.8 mL g-1 DM were higher （P〈0.001） than the other treatments, however,PF72 was lower （quadratic effect, P=0.0194） than the other levels. Both C and X had no effect （P〉0.05） on OMD, pH, ME, GY24, SCFA and MP. The combination of SB with EZ increased （P〈0.001） OMD, ME, SCFA, PFz2 and GP24, whereas there was no impact on pH. It could be concluded that addition of SB extract, C, and X effectively improved the in vitro rumen fermentation, and the combination of enzyme with SB extract at the level of 1.2 mL g-1 was more effective than the other treatments.展开更多
By screening sequence reads from the Salix suchowensis chloroplast （cp） genome that were generated by next-generation sequencing platforms, we assembled a complete circular pseudomolecule for the cp genome. This pse...By screening sequence reads from the Salix suchowensis chloroplast （cp） genome that were generated by next-generation sequencing platforms, we assembled a complete circular pseudomolecule for the cp genome. This pseudomolecule is 155,508 bp long and has a typical quadripartite structure that contains two single copy regions, a large single copy region （LSC, 84,385 bp）, and a small single copy region （SSC, 16,209 bp） separated by inverted repeat regions （IRs, 27,457 bp）. Gene annotation revealed that the S. suchowensis cp genome encoded 119 unique genes, including four ribosome RNA genes, 30 transfer RNA genes, 82 protein-coding genes, and three pseudogenes. Analysis of the repetitive sequences revealed 31 tandem repeats, 16 forward repeats, and five palindromic repeats. In addition, a total of 148 perfect microsatellites, which were characterized as A/T dominant in nucleotide composition, were detected. Significant shifting of the IR/SSC boundaries was revealed by comparing this cp genome with those of other rosid plants. We also constructed phylogenetic trees to demonstrate the phylogenetic position of S. suchowensis in Rosidae based on 66 orthologous protein-coding genes present in the cp genomes of 32 species. Sequencing 30 amplicons based on the pseudomolecule for experimental verification revealed 99.88% accuracy for the S. suchowensis cp genome assembly. Therefore, we assembled a high-quality pseudomolecule of the S. suchowensis cp genome, which is a useful resource for facilitating development of this shrub willow into a more productive bioenergy crop.展开更多
The microbial population in rotten living body of Salix matsudana caused by Trametes suaveolens (L.) was researched. 11 bacteria species (1 species of Bacillus, 2 species of Clostridium and 8 species of non-brood-cell...The microbial population in rotten living body of Salix matsudana caused by Trametes suaveolens (L.) was researched. 11 bacteria species (1 species of Bacillus, 2 species of Clostridium and 8 species of non-brood-cell bacteria), 1 species of Actinomyces that belongs to Lavendulac, 8 species of fungi and 6 species of Trichoderma were isolated from rotten trunk. The hyphae of Trametes suaveolens mainly existed between rotten sections and discoioration sections. In over-rotten section and healthy section the fungi (Trametes suaveolens) were not isolated. The microbes that lived in the discoloration section were the most in kinds and number and they were the pioneer microbes of wood rotting. Only after they dwelled in wood and eIiminated its rot-resistance,could wood-rotting fungi invade wood and caused wood-rotting.展开更多
The liquefied product of Salixpsammophila wood was separated by thin-layer chromatography （TLC） and column chromatography, and its structure was identified by nuclear magnetic resonance （NMR） spectra in our study....The liquefied product of Salixpsammophila wood was separated by thin-layer chromatography （TLC） and column chromatography, and its structure was identified by nuclear magnetic resonance （NMR） spectra in our study. The separation result indicates that the sample of liquefied S. psammophila contained at least two categories of components. The structure of the main components was guaiacyl C-1, C-2 of the hydroxyphenyl propane, i.e., the aromatic nucleus protons of lignin. Degradation and polycondensation reactions occurred when the S. psammophila wood was liquefied in phenol. Polycondensation reactions occurred among the depolymerization products from cellulose, the aromatic depolymerization products from lignin and the products of the displacement reactions between phenoxide ion and cellulose.展开更多
In order to extend the investigation of the characteristics of desert shrub liquefaction and the structure of liquefied desert shrubs, we studied the liquefaction of Salixpsammophila and Caragana intermedia in the pre...In order to extend the investigation of the characteristics of desert shrub liquefaction and the structure of liquefied desert shrubs, we studied the liquefaction of Salixpsammophila and Caragana intermedia in the presence of phenol and used FTIR analysis on unliquefied and liquefied S. psammophila and C. intermedia. The results showed that the liquefaction effects are enhanced with an increase in temperature, catalyst content and liquid ratio. FTIR analysis proved that more active functional groups appeared after S. psammophila and C. intermedia were liquefied in the presence of phenol. These results can provide a theoretical basis for the further utilization of liquefied S. psammophila and C. intermedia and the development of desert shrubs in a new utilization field.展开更多
Soil salinization is a serious ecological problem worldwide and information regarding the salt tolerance mechanisms of Salix is scarce.To elucidate the dynamic changes in the molecular mechanisms of Salix under salt s...Soil salinization is a serious ecological problem worldwide and information regarding the salt tolerance mechanisms of Salix is scarce.To elucidate the dynamic changes in the molecular mechanisms of Salix under salt stress,we generated gene expression profiles and examined changes in the expression of those genes.RNA-Seq was used to produce six cDNA libraries constructed from the leaves of Salix ×jiangsuensis CL‘J2345’treated with NaCl for 0,2,6,12,24 and 48 h.In total,249 million clean reads were assembled into 12,739 unigenes,all of which were clustered into 10 profiles based on their temporal expression patterns.KEGG analysis revealed that as an early defense response,the biosynthesis pathways of cutin,suberin and wax,which are involved in cell wall structure,were activated beginning at 2 h.The expression of secondary metabolism genes,including those involved in the phenylpropanoid,flavonoid,stilbenoid,diarylheptanoid and gingerol pathways,peaked at 6 h and 24 h;the upregulated genes were mainly involved in plant hormone pathways and beta-alanine,galactose and betalain metabolism.We identified roles of key phytohormones and found ETH to be the major signaling molecule activating TFs at 12 h;ETH,ABA,IAA and SA were the key molecules at 24 h.Moreover,we found that the upregulated genes were associated with elevated levels of amino acids,sucrose,inositol,stress proteins and ROS-scavenging enzymes,contributing to the maintenance of water balance.This research constitutes the first detailed analysis of salt stress-related mechanisms in Salix and identifies potential targets for genetic manipulation to improve yields.展开更多
Salix L.(willow)is the largest genus of the family Salicaceae and plays an important role in riparian habitats,wetlands and in shrub tundra.Due to the diff erent implications for the species belonging to this family,i...Salix L.(willow)is the largest genus of the family Salicaceae and plays an important role in riparian habitats,wetlands and in shrub tundra.Due to the diff erent implications for the species belonging to this family,it is fundamental to identify molecular tools characterizing relevant clones.A set of six multilocus and multiallelic simple sequence repeat(SSRs)markers are presented,leading to 390 polymorphic fragments considered as single dominant markers and able to discriminate successfully 92 S.alba L.from 24 Salix spp.The polymorphic fragments have been used to perform genetic diversity studies,and to investigate population structures and cluster analysis in a germplasm collection.The results highlight the capability of the six SSRs to be powerful genetic resources in applied forestry research,both to distinguish S.alba clones from Salix spp.and to perform genetic population studies for breeding programs.展开更多
文摘为探明荒漠植物沙柳（Salix psammophila）根围AM真菌时空异质性,2009年5月、8月和10月分别从内蒙古荒漠植物沙柳根围分0~10,11~20,21~30,31~40和41~50 cm 5个土层采集土壤样品,研究了AM真菌时空分布及与土壤因子的相关性.结果表明,沙柳根围AM真菌平均孢子密度为282个/100g,平均总定殖率0.642;从土壤中共分离AM真菌3属20种,其中球囊霉属（Glomus）15种、无梗囊霉属（Acaulospora）4种、盾巨孢囊霉属（Scutellospora）1种.AM真菌孢子密度、菌丝定殖率和丛枝定殖率随时间变化先升后降,最大值出现在8月;泡囊定殖率随时间变化先降后升,最大值出现在10月;随土壤深度增加,孢子密度和定殖率下降,最大孢子密度和最高定殖率均出现在10月份0~10 cm土层.孢子密度与土壤温度、pH极显著正相关,与土壤速效P极显著负相关;泡囊定殖率与土壤碱解N显著正相关;丛枝定殖率与土壤温度、湿度和pH极显著正相关,与土壤碱解N极显著负相关;菌丝定殖率与易提取球囊霉素极显著正相关.总球囊霉素和易提取球囊霉素与土壤碱解N和有机C极显著正相关.球囊霉素含量的动态变化能够综合反映土壤AM真菌分布和活动、有机C动态和养分循环进程,应作为荒漠土壤质量和功能评价的新指标进一步深入研究.
基金financial support from the IAEA, Vienna, Austria, Research Contract number MEX16307 within the D3.10.27 Coordinated Research Project
文摘An in vitro gas production （GP） technique was used to investigate the effects of combining different doses of Salix babylonica extract （SB） with exogenous fibrolytic enzymes （EZ） based on xylanase （X） and cellulase （C）, or their mixture （XC; 1：1 v/v） on in vitro fermentation characteristics of a total mixed ration of corn silage and concentrate mixture （50：50, w/w） as substrate. Four levels of SB （0, 0.6, 1.2 and 1.8 mL g-1 dry matter （DM）） and four supplemental styles of EZ （1 μL g-1 DM; control （no enzymes）, X, C and XC （1：1, v/v） were used in a 4×4 factorial arrangement. In vitro GP （mL g-1 DM） were recorded at 2, 4, 6, 8, 10, 12, 24, 36, 48 and 72 h of incubation. After 72 h, the incubation process was stopped and supernatant pH was determined, and then filtered to determine dry matter degradability （DMD）. Fermentation parameters, such as the 24 h gas yield （GY24）, in vitro organic matter digestibility （OMD）, metabolizable energy （ME）, short chain fatty acid concentrations （SCFA）, and microbial crude protein production （MCP） were also estimated. Results indicated that there was a SBxEZ interaction （P〈0.0001） for the asymptotic gas production （b）, the rate of gas production （c）, GP from 6 to 72 h, GP2 （P=0.0095）, and GP4 （P=0.02）. The SB and different combination of enzymes supplementation influenced （P〈0.001） in vitro GP parameters after 12 h of incubation; the highest doses of SB （i.e., 1.8 mL g-1 DM）, in the absence of any EZ, quadratically increased （P〈0.05） the initial delay before GP begins （L） and GP at different incubation times, with lowering b （quadratic effect, P〈0.0001 ） and c （quadratic effect, P〈0.0001 ; linear effect, P=0.0018）. The GP was the lowest （P〈0.05） when the highest SB level was combined with cellulose. There were SBxEZ interactions （P〈0.001） for OMD, ME, the partitioning factor at 72 h of incubation （PF72）, GY24, SCFA, MCP （P=0.0143）, and pH （P=0.0008）. The OMD, ME, GY24 and SCFA with supplementation of SB extract at 1.8 mL g-1 DM were higher （P〈0.001） than the other treatments, however,PF72 was lower （quadratic effect, P=0.0194） than the other levels. Both C and X had no effect （P〉0.05） on OMD, pH, ME, GY24, SCFA and MP. The combination of SB with EZ increased （P〈0.001） OMD, ME, SCFA, PFz2 and GP24, whereas there was no impact on pH. It could be concluded that addition of SB extract, C, and X effectively improved the in vitro rumen fermentation, and the combination of enzyme with SB extract at the level of 1.2 mL g-1 was more effective than the other treatments.
基金supported by the Key Forestry Public Welfare Project(201304102)the Natural Science Foundation of China(31400564 and 315005533)+1 种基金enabled by the Innovative Research Team of the Educational Department of Chinathe PAPD(Priority Academic Program Development)program at Nanjing Forestry University
文摘By screening sequence reads from the Salix suchowensis chloroplast （cp） genome that were generated by next-generation sequencing platforms, we assembled a complete circular pseudomolecule for the cp genome. This pseudomolecule is 155,508 bp long and has a typical quadripartite structure that contains two single copy regions, a large single copy region （LSC, 84,385 bp）, and a small single copy region （SSC, 16,209 bp） separated by inverted repeat regions （IRs, 27,457 bp）. Gene annotation revealed that the S. suchowensis cp genome encoded 119 unique genes, including four ribosome RNA genes, 30 transfer RNA genes, 82 protein-coding genes, and three pseudogenes. Analysis of the repetitive sequences revealed 31 tandem repeats, 16 forward repeats, and five palindromic repeats. In addition, a total of 148 perfect microsatellites, which were characterized as A/T dominant in nucleotide composition, were detected. Significant shifting of the IR/SSC boundaries was revealed by comparing this cp genome with those of other rosid plants. We also constructed phylogenetic trees to demonstrate the phylogenetic position of S. suchowensis in Rosidae based on 66 orthologous protein-coding genes present in the cp genomes of 32 species. Sequencing 30 amplicons based on the pseudomolecule for experimental verification revealed 99.88% accuracy for the S. suchowensis cp genome assembly. Therefore, we assembled a high-quality pseudomolecule of the S. suchowensis cp genome, which is a useful resource for facilitating development of this shrub willow into a more productive bioenergy crop.
文摘The microbial population in rotten living body of Salix matsudana caused by Trametes suaveolens (L.) was researched. 11 bacteria species (1 species of Bacillus, 2 species of Clostridium and 8 species of non-brood-cell bacteria), 1 species of Actinomyces that belongs to Lavendulac, 8 species of fungi and 6 species of Trichoderma were isolated from rotten trunk. The hyphae of Trametes suaveolens mainly existed between rotten sections and discoioration sections. In over-rotten section and healthy section the fungi (Trametes suaveolens) were not isolated. The microbes that lived in the discoloration section were the most in kinds and number and they were the pioneer microbes of wood rotting. Only after they dwelled in wood and eIiminated its rot-resistance,could wood-rotting fungi invade wood and caused wood-rotting.
基金supported by grants 200508010603 and 200711020504 from the key pro-ject of the Natural Science Foundation of the InnerMongolia Autonomous Region
文摘The liquefied product of Salixpsammophila wood was separated by thin-layer chromatography （TLC） and column chromatography, and its structure was identified by nuclear magnetic resonance （NMR） spectra in our study. The separation result indicates that the sample of liquefied S. psammophila contained at least two categories of components. The structure of the main components was guaiacyl C-1, C-2 of the hydroxyphenyl propane, i.e., the aromatic nucleus protons of lignin. Degradation and polycondensation reactions occurred when the S. psammophila wood was liquefied in phenol. Polycondensation reactions occurred among the depolymerization products from cellulose, the aromatic depolymerization products from lignin and the products of the displacement reactions between phenoxide ion and cellulose.
基金This study was financially supported by the Natural Science Foundation of Inner Mongolia(No.200508010603).
文摘In order to extend the investigation of the characteristics of desert shrub liquefaction and the structure of liquefied desert shrubs, we studied the liquefaction of Salixpsammophila and Caragana intermedia in the presence of phenol and used FTIR analysis on unliquefied and liquefied S. psammophila and C. intermedia. The results showed that the liquefaction effects are enhanced with an increase in temperature, catalyst content and liquid ratio. FTIR analysis proved that more active functional groups appeared after S. psammophila and C. intermedia were liquefied in the presence of phenol. These results can provide a theoretical basis for the further utilization of liquefied S. psammophila and C. intermedia and the development of desert shrubs in a new utilization field.
基金The work was supported by the National Natural Science Foundation of China(31400572)the Jiangsu Provincial Natural Science Foundation(BK20141039)National Natural Science Foundation of China(31300556).
文摘Soil salinization is a serious ecological problem worldwide and information regarding the salt tolerance mechanisms of Salix is scarce.To elucidate the dynamic changes in the molecular mechanisms of Salix under salt stress,we generated gene expression profiles and examined changes in the expression of those genes.RNA-Seq was used to produce six cDNA libraries constructed from the leaves of Salix ×jiangsuensis CL‘J2345’treated with NaCl for 0,2,6,12,24 and 48 h.In total,249 million clean reads were assembled into 12,739 unigenes,all of which were clustered into 10 profiles based on their temporal expression patterns.KEGG analysis revealed that as an early defense response,the biosynthesis pathways of cutin,suberin and wax,which are involved in cell wall structure,were activated beginning at 2 h.The expression of secondary metabolism genes,including those involved in the phenylpropanoid,flavonoid,stilbenoid,diarylheptanoid and gingerol pathways,peaked at 6 h and 24 h;the upregulated genes were mainly involved in plant hormone pathways and beta-alanine,galactose and betalain metabolism.We identified roles of key phytohormones and found ETH to be the major signaling molecule activating TFs at 12 h;ETH,ABA,IAA and SA were the key molecules at 24 h.Moreover,we found that the upregulated genes were associated with elevated levels of amino acids,sucrose,inositol,stress proteins and ROS-scavenging enzymes,contributing to the maintenance of water balance.This research constitutes the first detailed analysis of salt stress-related mechanisms in Salix and identifies potential targets for genetic manipulation to improve yields.
基金the Project“RGV-FAO”(The Italian Ministry of Agricultural,Food and Forestry Policies-MiPAAF D.M.18862/06).
文摘Salix L.(willow)is the largest genus of the family Salicaceae and plays an important role in riparian habitats,wetlands and in shrub tundra.Due to the diff erent implications for the species belonging to this family,it is fundamental to identify molecular tools characterizing relevant clones.A set of six multilocus and multiallelic simple sequence repeat(SSRs)markers are presented,leading to 390 polymorphic fragments considered as single dominant markers and able to discriminate successfully 92 S.alba L.from 24 Salix spp.The polymorphic fragments have been used to perform genetic diversity studies,and to investigate population structures and cluster analysis in a germplasm collection.The results highlight the capability of the six SSRs to be powerful genetic resources in applied forestry research,both to distinguish S.alba clones from Salix spp.and to perform genetic population studies for breeding programs.
