Influence of storage and pre-sowing treatment of southern sweet-grass seeds on their germination and initial growth of seedlings
Introduction: Southern sweet-grass (Hierochloë australis /Schrad./ Roem. et Schult., Poaceae) is a perennial tuft-grass occurring in North-Eastern part of Europe. Its leaves are collected from wild growing plants as an aromatic raw material used in alcohol industry. Due to overharvest, attempts to introduce the plant into cultivation have been undertaken. Objective: This work aims to assess the influence of southern sweetgrass seeds (spikelets) storage and pre-sowing treatment on their germination and the initial growth of seedlings. Methods: The seeds were assessed directly after harvest and after 6, 18 and 30 months of storage. The investigated parameters, i.e. 1000 seed weight, moisture content, germinability and viability of seeds (tetrazoline test) were determined according to ISTA. Results: After 30 months of storage, the germinability of seeds decreased from 42.6 (after harvest) to 4.6% but their viability remained high (70.9%). Stratification, short rinse of stratified seed in H2SO4 and application of KNO3 or GA3 had increased the seeds germination (over 70%). Conclusion: Southern sweetgrass seeds become dormant shortly after maturing. The improvement of germination requires the application of combined treatments, i.e. stratification, scarification and growth-promoting substances.