Line-scatter plots in chemotaxonomy of Genista L. Section Spartioides Spach in Western Europe

Abstract

Abstract Isoflavone patterns of Genista species from the section Spartioides in west Europe were reported. Orobol-8- C -glucoside, isoprunetin-7- O -glucoside, genistein-8- C -glucoside, genistein-6- C -glucoside, genistein-7- O -glucoside and a further, unknown isoflavone glycoside were detected in different amounts and proportions in most of the analysed Genista species. Line-scatter plots were developed to visualise the chemotaxonomic significance of the detected isoflavone glycosides. With these plots the influence of up to six characters could be demonstrated in one diagram. Line-scatter plots fill a gap between the widely used scatter plots and graphical presentations based on multivariate analysis of a large number of characters. The isoflavone patterns of the Genista specimens presented in line-scatter plots showed small intraspecific variation compared to their interspecific variation. In Genista chemotaxonomy, isoflavone patterns are useful additional characters on the species and partly on the subspecies level. This was confirmed in discriminant analysis. Together with other chemotaxonomic data (quinolizidine alkaloids), morphological, cytological, biogeographical and phytosociological characters, isoflavone patterns provided data for a species concept within the section. Further-more, the proposed subdivision of the section into the subsections Chamaespartum and Spartioides was supported by the clear differences of their isoflavone patterns. Isoflavones allowed a more detailed subdivision of the section Spartioides than alkaloid data.