Quality and viability of seeds were tested for six species of the genu
s Hibbertia (Fam.: Dilleniaceae). Hibbertia seeds of good quality are
heavier, of darker colouration, enclosed by a pulpy aril and sink to t
he bottom of a water container during the 'floating test'. However, se
ed quality testing only detects the obviously dead seeds, while the te
trazolium test has the potential to reveal actual viability of a seed.
Development of the tetrazolium test is considered to be particularly
valuable since seed dormancy mechanisms delay germination in many nati
ve Australian plant species in addition to species of the genus Hibber
tia.