Utility of RAPD Markers in Evaluating the Status of the Hawaiian Tree Fern Cibotium x heleniae

Randomly amplified polymorphic DNA (RAPD) markers provide data consistent with the conclusion based on morphological characters that the recently named taxon Cibotium x heleniae is indeed of hybrid origin. This assertion is supported by (1) placement of C. x heleniae intermediate to the parent taxa, as determined by genetic similarity data; (2) location of C. x heleniae individuals on a clade intermediate to the parent species in the cladistic analysis; and (3) clustering of the C. x heleniae individuals between clusters of parental individuals in principal components analysis. Additivity of parental genetic markers in the putative hybrid ranged from 54 to 64%, providing additional though modest support for the hypothesized origin of C. x heleniae. Our results indicate that RAPD data can be of considerable value in assessing potential hybridity of individuals in naturally occurring populations.