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The seed dispersal mechanisms of Salvia species are reviewed, with particular attention to quantitative or experimental evidence of dispersal. Despite having rather uniform fruit morphology. Salvia has several dispersal mechanisms: dispersal of mericarps by water (hydrochory), wind (anemochory), animals (zoochory) or gravity (barochory). Cases of mynnecochory are highlighted, along with dispersal by the plant itself via springy or hygroscopic pedicels. Despite having no visible means of dispersal, many Salvia species disperse for short to medium distances. Many gaps in our knowledge of dispersal exist, despite the fact that knowledge of dispersal mechanisms is critical in evaluating invasive potential, conservation status, usefulness in habitat restoration, and geographic distribution. Keywords Anemochory * Hydrochory * Lamiaceae * Salvia * Seed dispersal * Zoochory, Introduction Intraspecific gene flow is the means by which populations of sexually reproducing species establish genetic structure, i.e. maintain genetic diversity while at the same time preserve species coherence (Bohonak, [...]

Enzyme electrophoresis and restriction-fragment analysis of chloroplast DNA (cpDNA) and nuclear ribosomal DNA (rDNA) were used to test the hypothesis that both Helianthus neglectus and H. paradoxus are stabilized hybrid derivatives of H. annuus and H. petiolaris. The four species are annuals, diploid outcrossers, and have the same chromosome number. Helianthus annuus and H. petiolaris had the same allele in highest frequency for 16 of the 18 isozyme loci examined and had different majority alleles for only 6-Pgd3 and Pgi2. The two species had divergent rDNAs that could be distinguished by seven diagnostic restriction site mutations and three length mutations, and their cpDNAs could be differentiated by three diagnostic restriction site mutations. The alleles observed in H. neglectus were not a combination of those observed in H. annuus and H. petiolaris. Although H. neglectus had only one unique allele, it possessed none of the three alleles specific to H. annuus. In contrast, it had four of the seven alleles specific to H. petiolaris. Furthermore, H. neglectus had the same rDNA type as H. petiolaris and had the same cpDNA as that found in two populations of H. petiolaris ssp. fallax. These data allowed us to speculate that H. neglectus may be a recent derivative of H. petiolaris ssp. fallax, rather than a stabilized hybrid derivative as originally proposed. In contrast, H. paradoxus combined the alleles of H. annuus and H. petiolaris and had no unique alleles. At Adh2, H. paradoxus was monomorphic for an allele found only in H. petiolaris ssp. fallax, whereas at 6-Pgd3 and Pgi2, it was monomorphic for high frequency H. annuus alleles. Furthermore, H. paradoxus combined the rDNA repeat types of both proposed parents and had the chloroplast genome of H. annuus. These data provide compelling evidence that H. paradoxus, in contrast to H. neglectus, was derived via hybridization.