During post-harvest maturation, different species vary in the length of dormancy breaking or germination increases. Seed dormancy and slow seedling development often limit establishment of forage grass stands. Seed germination and seedling vigour of Italian ryegrass (Lolium italicum A. Braun, Synonym Lolium multiflorum L.), cocksfoot (Dactylis glomerata L.) and timothy (Phleum pretense L.) were observed after harvest and storage. After harvest in June, seeds were stored under standard storage conditions and sampled every 30 days after harvest (DAH), up to 270 DAH, and then every 60 days up to 990 DAH. At each date, seeds were tested for final germination percentage and for seedling vigour traits. Timothy seeds had a maximum germination (88%) and the best seedlings vigour at 90 DAH, which implies that early autumn (September-October) is the best sowing period for freshly harvested seeds of timothy. Timothy seed germination was poor from 270 DAH (73%). The best germination and vigour of Italian ryegrass and cocksfoot seedlings were between 270 and 330 DAH, which equates to spring sowing time (March-April) in the succeeding year. Cocksfoot and Italian ryegrass seeds maintained satisfactory germination levels up to 630 DAH (81%) and 810 DAH (81%), respectively. The data can serve for the determination of a proper storage duration management between harvest and sowing of the tested species under ambient conditions of south-eastern Europe.Index terms: Forage grasses, post-harvest maturation, seed dormancy. RESUMODurante o armazenamento, diferentes espécies comportam-se diferentemente quanto à dormência e crescimento de plântulas. A dormência o desenvolvimento lento das plântulas limitam a época do plantio das gramíneas forrageiras plurianuais. A germinação de sementes e o crescimento das plântulas de azevem italiano (Lolium italicum A. Braun sin. Lolium multiflorum L.), Dactilis (Dactilis glomerata L.) e de timoteo (Phleum pratense L.) foi pesquisada durante a maturação pós-colheita e a silagem. Após a colheita, em junho, sementes foram armazenadas em condições tradicionais e analisadas a cada 30 dias após a colheita, até 270 dias e, em seguida, a cada 60 dias até 990 dias. Nessa pesquisa, avaliou-se a germinação final e o vigor das plântulas. As sementes de timoteo obtiveram germinação máxima (88%) e o melhor crescimento das plântulas após 90 dias de armazenamento, indicando que o melhor período para o plantio das sementes colhidas em junho é o inicio de outono (setembro-outubro). A germinação de sementes de timoteo reduziu nos 270 dias (73%) seguintes. A melhor germinação, e crescimento da plântula do azevem italiano e do dactilis ocorreu entre 270 e 330 dias, indicando que a melhor época para plantio é na primavera (março-abril), do ano seguinte. As sementes de dactilis e azevem italiano mantiveram germinação satisfatória até 630 dias (81%) e 810 dias (81%), respectivamente. Essa pesquisa pode servir para determinação de gerenciamento adequado de duração de armazenamento entre a colheita e o plantio das esp...

In the past few years in Europe grass seed production declines. This tendency is especially pronounced in meadow fescue. Seed shedding and therefore yield losses are the problem in seed production. This can be reduced if seed of higher moisture contents is harvested. The impacts of drying temperatures of 70, 60, 50, 40 and 22°C on changes in dormancy and germination of seed harvested with moisture contents of 45, 35 and 25% were observed in the present study. The analysis was done immediately after seed drying, then three months later and eight months later. Seeds with the moisture content of 45% that were dried at 70°C were not dormant at all after harvest, but seeds were damaged, which resulted in reduced germination. Drying temperatures of 40°C and 50°C resulted in maximum germination of seed harvested with 45% moisture after three months. After eight months the best germination of all seeds was obtained at 22°C and 40°C. The seed ageing test confirmed faster deterioration of seeds harvested with higher moisture contents. Seed harvested with 25% moisture and dried at 22°C is the most suitable seed for longer storage.

After-ripening is a complex enzymatic and biochemical process resulting in the breakage of non-deep physiological dormancy. The experiment was set up to identify the minimum duration of storage after harvest for completion of afterripening in meadow (Festuca pratensis Huds.), tall (Festuca arundinacea Schreb.) and red fescue (Festuca rubra L.). The seeds were stored under ware-house conditions for 0, 30, 60, 90, 120, 150, 180, 210 and 240 days after harvest (DAH). After the storage periods, the seeds were tested for germination and the primary root length, shoot length and seedlings biomass were measured. The final counts in all three species amounted to 60-65% germination immediately after harvest, suggesting a medium level of embryonic dormancy. The after-ripening during storage improved the final germination in all three species with decreasing intensity. In meadow fescue, the final germination was significantly improved up to 150 DAH, while the seedling size did not change significantly. In tall and red fescue, after-ripening significantly improved the final germination up to 120 DAH, while the seedling size variables reached maximum values after 150 DAH. The obtained data can serve for the determination of proper storage duration management between harvest and sowing (autumn/spring) of the tested fescue species under agro-ecological conditions of south-eastern Europe.Additional key words: autumn and spring sowing, biomass, root length, seedling dormancy-breaking effect, shoot length. ResumenComunicación corta. Efecto del periodo de post-maduración sobre la germinación de semillas y crecimiento de plántulas en tres especies de festuca La post-maduración es un proceso enzimático y bioquímico complejo que resulta en la rotura de la latencia fisiológica poco profunda. El experimento se estableció para identificar el tiempo mínimo de almacenamiento después de la cosecha para la terminación de la post-maduración en festuca de prados (Festuca pratensis Huds.), festuca alta (Festuca arundinacea Schreb.) y festuca roja (Festuca rubra L.). Las semillas se almacenaron durante 0, 30, 60, 90, 120, 150, 180, 210 y 240 días después de la cosecha (DAH). Después de los períodos de almacenamiento, se analizó la germinación de las semillas y se midieron la longitud de la raíz primaria, la longitud del vástago y la biomasa de las plán-tulas. Las tres especies tuvieron 60-65% de germinación inmediatamente después de la cosecha, lo que indica un nivel medio de latencia de embriones. La post-maduración durante el almacenamiento mejoró la germinación final en las tres especies, con una intensidad decreciente. En F. pratensis la germinación final aumentó considerablemente hasta 150 DAH, mientras que el tamaño de plántulas no cambió significativamente. En F. arundinacea y F. rubra la postmaduración mejoró significativamente la germinación final hasta 120 DAH, mientras que el tamaño de las plántulas alcanzó valores máximos después de 150 DAH. Los datos obtenidos pueden servir para una gestión adecuada de la duración de almac...

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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.