Research note:: Effect of scarification and growing medium on seed germination of Desmanthus bicornotus

Desmanthus bicornotus is an herbaceous species with wide environmental adaptation and potential for reclamation and argoforestry systems. Little is known about the germination requirements of D. bicornotus and propagation methods are needed to further study the potential and future use of the species. Four scarification treatments (mechanical scarification and immersion in concentrated sulphuric acid for 10, 30 and 60 minutes) were tested under growth chamber and glasshouse conditions. Highest germination rates were obtained with acid scarification for 30 minutes under growth chamber conditions (99%) and for 10 minutes under glasshouse conditions (49%). Mechanical scarification was also efficient in promoting germination for growth chamber conditions (57%) but not for glasshouse conditions (12%) and was labour-intensive. Lowest germination was observed for untreated seeds in a growth chamber (3%) and for seeds scarified with sulphuric acid for 60 minutes under glasshouse conditions (2%). Our results suggest that short acid-scarification times ( < 10 minutes) would be most appropriate for propagating the species because damage to the seeds caused by longer exposure to acid would be reduced.