Effect of selected environmental factors on the seed germination of the invasive species Polygala myrtifolia (Polygalaceae) in Australia

Context Polygala myrtifolia L. has become a significant environmental weed in Australia, where it invaded coastal ecosystems temperate regions and there is high risk of extensive further spread. Knowledge seed-germination behaviour essential to understand the potential future impact this species.Aims We investigated effects selected factors dormancy on P. seed germination emergence improve management strategies.Methods Seeds were exposed light, temperature, pH, salinity, osmotic burial depth treatments assess responses, viability.Key results Non-dormant seeds readily germinated percentages (93.0–95.0%) under specific day–night temperatures 25°C–15°C regardless light conditions across all soil pH (75.0–100.0%). Salinities tolerated up 100mMNaCl (70.0% germination) before sharply declining. Germination reduced from 98.3% 40.0% at potentials −0.4MPa −0.6MPa respectively. Emergence was greatest surface (48.33%) absent depths 8cm.Conclusions during autumn, winter spring soils any pH. The species unlikely invade areas salinity; however, moderately tolerant low moisture germination.Implications There invading sensitive because its success. Preventing dispersal ensuring seedlings are controlled critical reducing impact. recommend that cultivation sale should be prohibited Australia prevent