SURVEY OF JUNIPERUS COMMUNIS (CUPRESSACEAE) L. VARIETIES FROM THE WESTERN UNITED STATES USING RAPD FINGERPRINTS

RAPD fingerprints were generated from seven wild populations of Juniperus communis L. to assess whether molecular data support subdivision into vars. saxatilis, jackii and sibirica, members of California Floristic Province, and depressa, a component of the Great Basin Floristic Province. Results from UPGMA and Neighbor Joining cluster analyses showed little correspondence between RAPD-derived distances and varietal boundaries. Juniperus communis var. jackii, in particular, was highly heterogeneous, lending support to the hypothesis that the characteristic growth habit of this serpentine dweller (elongated, sparsely branched lateral branches) is environmentally induced. In contrast to the RAPD results, nucleotide sequences of the ITS1 region of nuclear ribosomal DNA were identical in four of five var. jackii individuals sequenced, and the fifth exhibited three base substitutions.