Taxonomic investigation was carried out on six (6) varieties of Mangifera indica (Julie, Broken, Peter, Kerosene, Opioro and Big fibre) using chemosystematics evidence. Extracts obtained from the leaf of each variety ...Taxonomic investigation was carried out on six (6) varieties of Mangifera indica (Julie, Broken, Peter, Kerosene, Opioro and Big fibre) using chemosystematics evidence. Extracts obtained from the leaf of each variety were phyto-chemically screened and quantified. Gravimetric and spectroscopic approaches were adopted in the quantification of active principles common to all the six varieties. Binary matrices computed from qualitative assessment were analysed to yield a dendrogram using the Average Linkage Method. Quantitative values were subjected to appropriate descriptive and inferential statistical analysis. All varieties possessed alkaloid except Big-fibre. Peter and Kerosene varieties lacked saponin, an active principle present in other varieties. Anthraquinone was present in all except in Julie and Opioro. Five out of the six varieties lacked phlobatannin. All varieties had tannin, steroid, flavonoid and reducing sugar. Tannin was lowest in Big-fibre (0.43%) but highest in Opioro (2.41%). Steroid ranged from 3.8% in Opioro to 9.0% in Julie with a standard deviation of 1.84. Julie variety recording the lowest composition in flavonoid (0.01%) and reducing sugar (0.04%) components was notable. Comparison of the mean values of phytochemicals has shown a statistically significant difference (p = 0.0005) with a large F-value (18.244). Using the LSD mean separation, steroid was the most remarkable phytochemical contributing to the significant differences. Dendrogram revealed very close relationship between Julie and Opioro varieties. The remaining four were divergent and distinct although Broken and Peter varieties arose from the same ancestral lineage with Julie and Opioro. However, Big-fibre and Kerosene varieties were clearly different from rest belonging to a different phylogenetic ancestor. With these remarkable differences, they ought to be given special taxonomic and systematic review for appropriate nomenclatural assignment. The six varieties of Mangifera indica investigated are thus clearly partitioned and therefore recommended to be circumscribed. This approach is maiden, and considered innovative as it is employed in this study for the first time in the taxonomy of Mangifera.展开更多
The taxonomic and nomenclatural history of the genus Ganoderma and related basidiomycetes is reviewed and compared to recent studies on its molecular phylogeny.A basidiomycete belonging to the genus Ganoderma can ofte...The taxonomic and nomenclatural history of the genus Ganoderma and related basidiomycetes is reviewed and compared to recent studies on its molecular phylogeny.A basidiomycete belonging to the genus Ganoderma can often rather easily be recognised in the field from the macromorphological characters of the sporocarp.The most important species and lineages can also be discriminated well by molecular phylogeny.However,the application of incongruent species concepts and the frequent misapplication of European names by chemists and other non-taxonomists have created confusion in the scientific literature.The identity of the species reported in the course of mycochemical studies can often not be verified,since no voucher material was retained.In this review,an overview on the most important types of specific chemotaxonomic traits(i.e.,secondary metabolites of the basidiomes and mycelia)reported from the genus is provided.Albeit certain triterpenoids such as ganoderic and lucidenic acids,steroids(e.g.ergosterol)and triterpenes(e.g.friedelin)appear to have some chemotaxonomic value at the generic rank,their relevance for species discrimination remains to be assessed.We propose that all important names in Ganoderma should be,as required,epitypified by fresh collections for which living cultures should be made available and that these should be examined by a combination of morphological,chemotaxonomic and molecular phylogenetic methods to attain a more stable taxonomy.展开更多
文摘Taxonomic investigation was carried out on six (6) varieties of Mangifera indica (Julie, Broken, Peter, Kerosene, Opioro and Big fibre) using chemosystematics evidence. Extracts obtained from the leaf of each variety were phyto-chemically screened and quantified. Gravimetric and spectroscopic approaches were adopted in the quantification of active principles common to all the six varieties. Binary matrices computed from qualitative assessment were analysed to yield a dendrogram using the Average Linkage Method. Quantitative values were subjected to appropriate descriptive and inferential statistical analysis. All varieties possessed alkaloid except Big-fibre. Peter and Kerosene varieties lacked saponin, an active principle present in other varieties. Anthraquinone was present in all except in Julie and Opioro. Five out of the six varieties lacked phlobatannin. All varieties had tannin, steroid, flavonoid and reducing sugar. Tannin was lowest in Big-fibre (0.43%) but highest in Opioro (2.41%). Steroid ranged from 3.8% in Opioro to 9.0% in Julie with a standard deviation of 1.84. Julie variety recording the lowest composition in flavonoid (0.01%) and reducing sugar (0.04%) components was notable. Comparison of the mean values of phytochemicals has shown a statistically significant difference (p = 0.0005) with a large F-value (18.244). Using the LSD mean separation, steroid was the most remarkable phytochemical contributing to the significant differences. Dendrogram revealed very close relationship between Julie and Opioro varieties. The remaining four were divergent and distinct although Broken and Peter varieties arose from the same ancestral lineage with Julie and Opioro. However, Big-fibre and Kerosene varieties were clearly different from rest belonging to a different phylogenetic ancestor. With these remarkable differences, they ought to be given special taxonomic and systematic review for appropriate nomenclatural assignment. The six varieties of Mangifera indica investigated are thus clearly partitioned and therefore recommended to be circumscribed. This approach is maiden, and considered innovative as it is employed in this study for the first time in the taxonomy of Mangifera.
基金We are grateful to Jens H.Petersen and Thomas Læssøe,who kindly allowed us to publish images of Ganoderma from their website(www.mycokey.com),and to David L.Hawksworth and Scott Redhead for valuable discussions.Moreover,we greatly appreciate the help of Y.-L.Yao(Beijing)and co-workers in locating the specimens that are depicted in Fig.4.
文摘The taxonomic and nomenclatural history of the genus Ganoderma and related basidiomycetes is reviewed and compared to recent studies on its molecular phylogeny.A basidiomycete belonging to the genus Ganoderma can often rather easily be recognised in the field from the macromorphological characters of the sporocarp.The most important species and lineages can also be discriminated well by molecular phylogeny.However,the application of incongruent species concepts and the frequent misapplication of European names by chemists and other non-taxonomists have created confusion in the scientific literature.The identity of the species reported in the course of mycochemical studies can often not be verified,since no voucher material was retained.In this review,an overview on the most important types of specific chemotaxonomic traits(i.e.,secondary metabolites of the basidiomes and mycelia)reported from the genus is provided.Albeit certain triterpenoids such as ganoderic and lucidenic acids,steroids(e.g.ergosterol)and triterpenes(e.g.friedelin)appear to have some chemotaxonomic value at the generic rank,their relevance for species discrimination remains to be assessed.We propose that all important names in Ganoderma should be,as required,epitypified by fresh collections for which living cultures should be made available and that these should be examined by a combination of morphological,chemotaxonomic and molecular phylogenetic methods to attain a more stable taxonomy.
