Seed Morphology and Protein Patterns (SDS-PAGE) as a Mean in Classification of Some Taxa of the Subfamily Mimosoideae (Fabaceae)

Aims: This study is developed to discuss whether the plant morphology and seed characters (macro and micromorphological and protein pattern) can provide an additional fundamental tool helping in explanation of the taxonomic trends at specific and infra-specific level within the 47 studied taxa belonging to subfamily Mimosoideae (Fabaceae) and to compare the proposed taxonomic treatment based on numerical analysis (dendrogram) with other previous and current systems of classification.
Methodology: The macro and micromorphological characters of the whole plant and seed as well as seed protein pattern of 47 taxa of subfamily Mimosoideae, family Fabaceae were investigated (using LM, SEM and Stereomicroscope and SDS-PAGE technique respectively). The taxa under investigation represent three tribes, seven genera and 46 species including three subspecies. The macro and micromorphological criteria (219 attributes) and seed protein pattern attributes (38 bands) extracted were numerically analyzed using NTsys-Pc program (version 2.02).
Results: The taxonomic treatment of the Mimosoideae taxa under investigation were based on the numerical analysis of 257 macro-, micromorphology of whole plant and seed protein attributes. The dendrogram interprets the similarities and dissimilarities between the investigated taxa. The dendrogram revealed that the taxa under investigation were split into two main series and 25 groups. The splitting Series I includes 12 groups which represented by 20 of the studied Acacia species. Series II includes 13 groups which represented by 15 sp. of Acacia and the species of other six studied genera, group 17 as well as group 21 contain species from different genera. The specific and infra-specific relationships were discussed and compared with some current systems of classification.
Conclusion: There is no difference of opinion about the phyletic position of the Acacieae which is always considered a link between Mimoseae and Ingeae. However different affinities of the genus Acacia taken as a natural unit have been suggested. The tribe Mimoseae represents the polymorphic and older core of Mimosoideae.