SEED GERMINATION OF LILIUM x FORMOLONGI AS INFLUENCED BY TEMPERATURE AND PLANT GROWTH REGULATORS
Seed germination of L. x formolongi Thunb., 'Snow Line' as influenced by presowing treatment at 5°C or with plant growth regulators and constant and alternating germination temperatures was investigated to obtain uniform seedlings. Seed germination was promoted at constant 17°C (test 1) or 14°C (test 2) and inhibited at constant 26°C (test 1) or to 29°C (test 2). Pre-treatment at 5°C did not overcome inhibition of seed germination induced by high temperatures. When seeds were exposed to alternating temperatures (29°C for 1 week followed by 14°C), germination percentage and the number of uniform seedlings was increased (Test 4). However, this response was not observed when seeds were exposed to 26°C and then germinated at 17°C (Test 3). Treatments with plant growth regulators did not affect germination either at 14°C or 29°C. To obtain uniform seedling populations, seeds should be germinated seeds at 14°C with pre-treatment at 29°C for 1 week. The ineffectiveness of a pre-treatment at 5°C on germination and inhibition of germination at >20°C suggests that L. x formolongi seeds exhibit imposed secondary dormancy by high temperatures during germination.
Roh, Mark S. and Sim, Y. (1996). SEED GERMINATION OF LILIUM x FORMOLONGI AS INFLUENCED BY TEMPERATURE AND PLANT GROWTH REGULATORS. Acta Hortic. 414, 243-250