Alkane composition diversity among populations of dwarf forms of Juniperus communis L.: Comparison between western Europe and northern American populations

Abstract

The cuticular wax composition of leaves has been analysed in three western European populations (Corsica, central Pyrenees, northern Alps) of Juniperus communis var. saxatilis Pall. (= J. nana Willd., nom illeg.) and in one population of J. communis L. var. depressa Pursh. from North America (Sierra Nevada). Gas chromatography shows the presence of 13 alkanes in all samples ranging from C23 to C35 with important intraspecific polymorphism in alkane content. The dominant alkanes range from C33 to C35. Alkanes C21 and C22 were found only in Corsica and Sierra Nevada populations. Canonical discriminant analysis separated the J. communis L. var. depressa Pursh. of the population of Sierra Nevada from other populations of J. communis var. saxatilis Pall. on the basis of their higher C31 content and the constant presence of C21 and C22 alkanes. J. communis var. saxatilis Pall. populations from the Pyrenees are close to northern Alps populations characterized by high concentrations of C33, C34 and C35 alkanes. This paper confirms the existence of Juniperus var. saxatilis Pall. in the Pyrenees (France). © The Linnean Society of London.