Estimation of mating system parameters in Hedysarum coronarium L. (Leguminoseae, Fabaceae)

Appropriate knowledge of genetic variation and mating systems is necessary to optimise conservation and utilisation of genetic resources. The present study provides estimates of mating system parameters in three natural popul ations of Hedysarum coronarium, using isozyme markers. There was no detecta ble variation among populations of single- and multilocus outcrossing rates (t(s), t(m)), which did not differ significantly from complete outcrossing . However, in pooled populations, estimates of t(s) (0.820 +/- 0.073) and t (m) (0.830 +/- 0.069) were both significantly different from the unity. The fixation index (F) and the biparental inbreeding rate, given by the differ ence between t(m) and t(s), were not significantly different from zero. t(m ) and t(s), estimated at the seedling stage, were both smaller than those d etermined at the adult phase, indicating some inbreeding depression acting between these two stages.