ZLV Online

Abstract

The objective of our study was to determine the effect of different pre-chilling periods (3, 4, 5, 6, and 7 weeks) and temperature (20 °C or 20/30 °C) on germination and emergence of three, European silver fir seed lots. Pre-chilling was done on moist filter paper at 3 °C for 3, 4, 5, 6, and 7 weeks and afterward the seeds were germinated for 28 days at 20 °C or 20/30 °C in a germination cabinet. In April, seeds pre-chilled for 3, 6, and 7 weeks were also sown outdooors in a commercial potting mix. Dormant (without chilling) seeds were sown outside in March, six weeks earlier than chilled seeds. Pre-chilling for 6 or 7 weeks significantly increased germination rate compared to 3 or 4 weeks while germination capacity of seeds pre-chilled for various periods did not differ. Higher, but not statistically significant germination occurred for all three seed lots pre-chilled 3 or 4 weeks and germinated at 20/30 °C (62–85%) compared to 20 °C (54–78%). Emergence of chilled seeds (38–68%) did not differ significantly from non-stratified seeds sown 6 weeks earlier (40–63%), but pre-chilled seeds emerged within 9 weeks, while non-stratified seeds needed 15 weeks. Chilling for 6 or 7 weeks accelerated emergence compared to 3 weeks chilling.