We studied the molecular mechanism of the quality traits of wood formation in larch.We used the immature latewood cells of two Japanese larch(Larix kaempferi)clones with significant differences in density and in micro...We studied the molecular mechanism of the quality traits of wood formation in larch.We used the immature latewood cells of two Japanese larch(Larix kaempferi)clones with significant differences in density and in microfibrillar angle(MFA)as materials to analyze their gene expression profiles.A total of 1735 differentially expressed genes were detected in immature latewood cells of the two clones,among which,971 were up-regulated and 764 were down-regulated.Digital gene expression profiling analysis revealed that genes encoding transcription factor members NAC66 and R2R3-MYB4,microtubule-associated protein,actin-related protein,cell wall protein members,arabinogalactan protein,Fasciclin-like arabinogalactan protein and glycine-rich protein,and several cell-wall-synthesis genes affected wood density and MFA by regulating latewood formation at transcriptional level.Our study results represent a basis for selection of quality traits and genetic improvement of larch wood.展开更多
Larch wood is structurally classifi ed in many countries as one of conifers with the highest load-bearing capacity(strength class of C30).The Spanish visual classifi cation regulation only assigns a strength class to ...Larch wood is structurally classifi ed in many countries as one of conifers with the highest load-bearing capacity(strength class of C30).The Spanish visual classifi cation regulation only assigns a strength class to 4 pine woods:Laricio pine(Pinus nigra Arn.var.Salzmannii),Silvestre pine(Pinus sylvestris L.),Radiata pine(Pinus radiata D.Don),and Pinaster pine(Pinus pinaster Ait.).This work adds to the number of structurally characterised species by creating a visual classifi cation table for Japanese larch wood(Larix kaempferi(Lamb.)Carr.)which diff erentiates between 2 visual classes,MEG-1 and MEG-2.Characteristic strength values were calculated for each class(fk,MEG-1=31.80 MPa,f k,MEG-2=24.55 MPa),mean module of elasticity(E 0,mean,MEG-1=13,082 MPA,E 0,mean,MEG-2=12,320 MPA)and density(ρk,MEG-1=456.6 kg m−3,ρk,MEG-2=469.1 kg m−3),before fi nally assigning a strength class of C30 to visual class MEG-1,and a strength class of C24 to visual class MEG-2.展开更多
基金supported by the Special Fund for Forest Scientific Research in the Public Welfare(201504104)the Fundamental Research Funds for the Central Non-profit Research Institution of CAF(CAFYBB2017ZA001)
文摘We studied the molecular mechanism of the quality traits of wood formation in larch.We used the immature latewood cells of two Japanese larch(Larix kaempferi)clones with significant differences in density and in microfibrillar angle(MFA)as materials to analyze their gene expression profiles.A total of 1735 differentially expressed genes were detected in immature latewood cells of the two clones,among which,971 were up-regulated and 764 were down-regulated.Digital gene expression profiling analysis revealed that genes encoding transcription factor members NAC66 and R2R3-MYB4,microtubule-associated protein,actin-related protein,cell wall protein members,arabinogalactan protein,Fasciclin-like arabinogalactan protein and glycine-rich protein,and several cell-wall-synthesis genes affected wood density and MFA by regulating latewood formation at transcriptional level.Our study results represent a basis for selection of quality traits and genetic improvement of larch wood.
基金We thanks to Basque centre of research and applied innovation in vet(TKNIKA),Centre for services and promotion of Castilla y León forestry and its industry(CESEFOR),D.Bixente Dorronsoro,Gipuzkoa provincial council,and Commercial services of the wood of Guipuzkoa(SECOMA).Larranaga sawmill(Azpeitia).
文摘Larch wood is structurally classifi ed in many countries as one of conifers with the highest load-bearing capacity(strength class of C30).The Spanish visual classifi cation regulation only assigns a strength class to 4 pine woods:Laricio pine(Pinus nigra Arn.var.Salzmannii),Silvestre pine(Pinus sylvestris L.),Radiata pine(Pinus radiata D.Don),and Pinaster pine(Pinus pinaster Ait.).This work adds to the number of structurally characterised species by creating a visual classifi cation table for Japanese larch wood(Larix kaempferi(Lamb.)Carr.)which diff erentiates between 2 visual classes,MEG-1 and MEG-2.Characteristic strength values were calculated for each class(fk,MEG-1=31.80 MPa,f k,MEG-2=24.55 MPa),mean module of elasticity(E 0,mean,MEG-1=13,082 MPA,E 0,mean,MEG-2=12,320 MPA)and density(ρk,MEG-1=456.6 kg m−3,ρk,MEG-2=469.1 kg m−3),before fi nally assigning a strength class of C30 to visual class MEG-1,and a strength class of C24 to visual class MEG-2.