APPLICATION OF CHEMOTAXONOMY OF LEAFY SPURGES (EUPHORBIA SPP) IN BIOLOGICAL-CONTROL

Triterpenoid profiles from latex of 56 accessions of European leafy spurges (Euphorbia spp.) were analyzed by gas - liquid chromatography. Qualitative and quantitative differences for components of the profiles were employed to distinguish between accessions. Triterpenoid profiles were diagnostic for the species, E. amygdaloides, E. agraria, E. cyparissias, E. lucida, and E. seguierana and were similar for each of these species in accessions collected from distant areas of Europe. By contrast, the 37 accessions of the E. esula complex were separated into 15 groups on qualitative and quantitative differences for components in the profiles. Identical profiles were detected among neighbouring accessions as well as those in collections from widely distant sites; conversely, different profiles also were identified for such collections. Profiles among these groups were compared with profiles of 39 United States (US) accessions of leafy spurge from Montana, Nebraska, North Dakota, and South Dakota. Profiles of US accessions, which were less variable than those from Europe, grouped into only 3 of the 15 European groups, whereas one US group could not be placed directly into a European group. This study demonstrates that latex analyses of European leafy spurges can distinguish between spurge populations and will identify potential plant sources of biocontrol agents for application against their leafy spurge counterparts in North America.