Effect of seed storage on seed germination and seedling quality of <i>Festulolium</i> in comparison with related forage grasses
Tests of seed germination, seed dormancy and seedling growth were performed on 0-, 6-, 20- and 30-months-old seed lots of Festulolium in comparison with Italian ryegrass (Lolium multiflorum) and meadow fescue (Festuca pratensis). Tests were performed on seeds harvested in 2 different years (2014 and 2015) resulting in no major difference between the years. Seed storage affected seed viability and dormancy and seedling growth in all 3 grasses. The maximum germination of Festulolium seeds was achieved 6 months after harvest (95% normal seedlings); germination decreased significantly thereafter. While maximum germination of L. multiflorum and F. pratensis seeds was also achieved following storage for 6 months, these germination rates (93 and 90%, respectively) were retained until at least 20 months in storage. After storage for 30 months, seed germination of Festulolium, L. multiflorum and F. pratensis had declined to 72, 79 and 83%, respectively. High germination in all species was associated with higher rates of seedling growth. In an artificial seed ageing test, a temperature of 41 °C (during 48 and 72 hours) was found to effectively rank seed lots for germination performance in all 3 grasses. This test seems to have application for use in the seed trade to identify seed lots which could deteriorate more rapidly in storage. Further studies are needed to verify this hypothesis.