CHARACTERISTIC LICHEN PRODUCTS IN CULTURES OF CHEMOTYPES OF THE RAMALINA-SILIQUOSA COMPLEX

Sixteen characteristic aromatic lichen products were identified in alga-free fungal cultures derived from single-spore isolates of four chemotypes of the Ramalina siliquosa species complex. The chemistries of many cultures are more complex than those of natural thalli. The compounds identified include the major beta-orcinol depsidones that characterize the chemotypes as well as biogenetically reasonable precursors not yet proved in natural thalli. Single-spore progeny from natural thalli can be assigned to chemotype without being lichenized with an alga. This result simplifies the use of secondary-product chemistry as a genetic marker to assess the limits of gene flow between chemotypes in natural populations.