To bridge the specific subject areas in plant systematics and evolution, encompassing evolutionary, phylogenetic, and genomic and biogeographically studies, this compendium reviews the current field of biosystematics, particularly the evolution of natural biota, and how plant biosystematics can contribute to the welfare of humans. A wide ranging biosystematic interest puts emphasis with the help of cytological and cytogenetic methods on getting to know chromosome variation within the family, genus and species connected with the phenomena of hybridization and polyploidization.