The Cheng index distinguishes indica andjaponica rice based on six taxonomic traits.This index has been widely used for classifi- cation of indica and japonica varieties in China.In this study,a double haploid(DH)popu...The Cheng index distinguishes indica andjaponica rice based on six taxonomic traits.This index has been widely used for classifi- cation of indica and japonica varieties in China.In this study,a double haploid(DH)popula-tion derived from anther culture of ZYQ8/JX17 F,a typical inter-subspecies hybrid,was used to investigate the six taxonomictraits,i.e.leaf hairiness(LH),color of hullwhen heading(CHH),hairiness of hull(HH),length of the first and second panicle internode(LPI),length/width of grain(L/W),andphenol reaction(PH).The morphological in- dex(MI)was also calculated.Based on themolecular linkage map constructed from this展开更多
The archaeological site of the Sanxingdui may date back as far as 5,000 years ago. The typical profiles of Palaeo-Stagnic-Anthrosols near the ancient site were selected, which aimed to identify diagnostic horizons emp...The archaeological site of the Sanxingdui may date back as far as 5,000 years ago. The typical profiles of Palaeo-Stagnic-Anthrosols near the ancient site were selected, which aimed to identify diagnostic horizons employing methodology of soil taxonomic classification and to reveal the micromorphological properties of the paleosols. Under long-term anthropogenic mellowing, the discernible differentiation between anthrostagnic epipedon and its subhorizons as well as hydragric horizon and its subhorizons occurred in Paleo-Stagnie-Anthrosols at the archaeological site of the Sanxingdui. The mieromorphological properties diversified among each specific diagnostic subhorizon, e.g., the developed microstructure in cultivated subhorizon within anthrostagnic epipedon, closely arranged particles and considerable micropores beneficial to both of water conservation and filtration in plow subhorizon within anthrostagnic epipedon, and automorphic optical-orientation clays and calcareous corrosion in hydragric horizons. The findings above of micromorphological features related with diagnostic horizons are significant for soil taxonomic classification.展开更多
According to the literature data on the chemical composition of the Trichilia genus performed in this work, it can be concluded that 334 different compounds were isolated and identified, distributed in monoterpenes, s...According to the literature data on the chemical composition of the Trichilia genus performed in this work, it can be concluded that 334 different compounds were isolated and identified, distributed in monoterpenes, sesquiterpenes, diterpenes, triterpenes, steroids, limonoids, coumarins, flavonoids, lignans, phenolic acids, amino acids and lactones. Together with the structures of this compound, data from botanical classification and pharmaco-logical results from extracts and pure compounds on the Trichilia genus were also described. The compounds derived from terpenes pathway were more significant, corresponding to about 87.7% of isolated and identified compounds from various Trichilia species. Among the different terpenoid skeletons of this kind, limonoids were meanly reported, appearing a total of 33.9% of compounds isolated from several Trichilia species.展开更多
Arbuscular mycorrhizal fungi(AMF)are plant root symbionts that play key roles in plant growth and soil fertility.They are obligate biotrophic fungi that form coenocytic multinucleated hyphae and spores.Numerous studie...Arbuscular mycorrhizal fungi(AMF)are plant root symbionts that play key roles in plant growth and soil fertility.They are obligate biotrophic fungi that form coenocytic multinucleated hyphae and spores.Numerous studies have shown that diverse microorganisms live on the surface of and inside their mycelia,resulting in a metagenome when whole-genome sequencing(WGS)data are obtained from sequencing AMF cultivated in vivo.The metagenome contains not only the AMF sequences,but also those from associated microorganisms.In this study,we introduce a novel bioinformatics program,Spore-associated Symbiotic Microbes(SeSaMe),designed for taxonomic classification of short sequences obtained by next-generation DNA sequencing.A genus-specific usage bias database was created based on amino acid usage and codon usage of a three consecutive codon DNA 9-mer encoding an amino acid trimer in a protein secondary structure.The program distinguishes between coding sequence(CDS)and non-CDS,and classifies a query sequence into a genus group out of 54 genera used as reference.The mean percentages of correct predictions of the CDS and the non-CDS test sets at the genus level were 71% and 50% for bacteria,68% and 73% for fungi(excluding AMF),and 49% and 72% for AMF(Rhizophagus irregularis),respectively.SeSaMe provides not only a means for estimating taxonomic diversity and abundance but also the gene reservoir of the reference taxonomic groups associated with AMF.Therefore,it enables users to study the symbiotic roles of associated microorganisms.It can also be applicable to other microorganisms as well as soil metagenomes.SeSaMe is freely available at www.fungalsesame.org.展开更多
文摘The Cheng index distinguishes indica andjaponica rice based on six taxonomic traits.This index has been widely used for classifi- cation of indica and japonica varieties in China.In this study,a double haploid(DH)popula-tion derived from anther culture of ZYQ8/JX17 F,a typical inter-subspecies hybrid,was used to investigate the six taxonomictraits,i.e.leaf hairiness(LH),color of hullwhen heading(CHH),hairiness of hull(HH),length of the first and second panicle internode(LPI),length/width of grain(L/W),andphenol reaction(PH).The morphological in- dex(MI)was also calculated.Based on themolecular linkage map constructed from this
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No KZCX2-YW-409)
文摘The archaeological site of the Sanxingdui may date back as far as 5,000 years ago. The typical profiles of Palaeo-Stagnic-Anthrosols near the ancient site were selected, which aimed to identify diagnostic horizons employing methodology of soil taxonomic classification and to reveal the micromorphological properties of the paleosols. Under long-term anthropogenic mellowing, the discernible differentiation between anthrostagnic epipedon and its subhorizons as well as hydragric horizon and its subhorizons occurred in Paleo-Stagnie-Anthrosols at the archaeological site of the Sanxingdui. The mieromorphological properties diversified among each specific diagnostic subhorizon, e.g., the developed microstructure in cultivated subhorizon within anthrostagnic epipedon, closely arranged particles and considerable micropores beneficial to both of water conservation and filtration in plow subhorizon within anthrostagnic epipedon, and automorphic optical-orientation clays and calcareous corrosion in hydragric horizons. The findings above of micromorphological features related with diagnostic horizons are significant for soil taxonomic classification.
基金The authors are thankful to FAPERJ,Fundacao Carlos Chagas Filho de AmparoàPesquisa do Estado do Rio de Janeiro(N˚do Processo E-26/111.898/2012)for financial support.
文摘According to the literature data on the chemical composition of the Trichilia genus performed in this work, it can be concluded that 334 different compounds were isolated and identified, distributed in monoterpenes, sesquiterpenes, diterpenes, triterpenes, steroids, limonoids, coumarins, flavonoids, lignans, phenolic acids, amino acids and lactones. Together with the structures of this compound, data from botanical classification and pharmaco-logical results from extracts and pure compounds on the Trichilia genus were also described. The compounds derived from terpenes pathway were more significant, corresponding to about 87.7% of isolated and identified compounds from various Trichilia species. Among the different terpenoid skeletons of this kind, limonoids were meanly reported, appearing a total of 33.9% of compounds isolated from several Trichilia species.
文摘Arbuscular mycorrhizal fungi(AMF)are plant root symbionts that play key roles in plant growth and soil fertility.They are obligate biotrophic fungi that form coenocytic multinucleated hyphae and spores.Numerous studies have shown that diverse microorganisms live on the surface of and inside their mycelia,resulting in a metagenome when whole-genome sequencing(WGS)data are obtained from sequencing AMF cultivated in vivo.The metagenome contains not only the AMF sequences,but also those from associated microorganisms.In this study,we introduce a novel bioinformatics program,Spore-associated Symbiotic Microbes(SeSaMe),designed for taxonomic classification of short sequences obtained by next-generation DNA sequencing.A genus-specific usage bias database was created based on amino acid usage and codon usage of a three consecutive codon DNA 9-mer encoding an amino acid trimer in a protein secondary structure.The program distinguishes between coding sequence(CDS)and non-CDS,and classifies a query sequence into a genus group out of 54 genera used as reference.The mean percentages of correct predictions of the CDS and the non-CDS test sets at the genus level were 71% and 50% for bacteria,68% and 73% for fungi(excluding AMF),and 49% and 72% for AMF(Rhizophagus irregularis),respectively.SeSaMe provides not only a means for estimating taxonomic diversity and abundance but also the gene reservoir of the reference taxonomic groups associated with AMF.Therefore,it enables users to study the symbiotic roles of associated microorganisms.It can also be applicable to other microorganisms as well as soil metagenomes.SeSaMe is freely available at www.fungalsesame.org.
