Contributions to the Molecular Biology of Kelp

Genetic relatedness between various kelp (Order Laminariales, Class Phaeophyceae, Division Heterokontophyta) taxa was investigated using DNA sequencing and PCR-typing. The rDNA ITS1 region of gametophytes generated by a naturally occurring apparent kelp hybrid of Macrocystis C. Agardh and Pelagophycus Areschoug were sequenced to determine parentage. All gametophytes examined had only Macrocystis rDNA suggesting either a non-hybrid, or more complicated hybridization than pure equal parental contribution occurred. Laboratory-generated intergeneric hybrids of Alaria Greville and Lessoniopsis Reinke were examined for parentage based on rDNA regions amplified using PCR. Both parental rDNA types were visible in one identified possible hybrid and non-hybrids were easily distinguished. Actin introns in both Alaria and Nereocystis Postels & Ruprecht were characterized and sequenced, representing the first actin intron sequences examined in the Heterokontophyta. The second actin intron fiom individuals of three Alaria species, spanning a geographic range of hundreds of kilometres, were sequenced to quantify variation and to examine individual relatedness for usage in studies of gene flow and population subdivision. Relatedness seemed to correlate with oceanographic distance but not with accepted species boundaries.