Flowering in celeriac (Apium graveolens L. var. rapaceum (Mill.) DC.): effects of photoperiod

Apium Plants: Beyond Simple Food and Phytopharmacological Applications

“…All varieties of celery, including A. graveolens, grow in climate conditions with a long, cool season and monthly mean temperatures of 15-21 • C, and therefore cultivation usually starts during autumn or early winter [36,46,47]. All varieties need abundant moisture during their growing, otherwise their roots can be small and hard.…”

“…Such conditions are preferable when plants are meant for seed or dry fruit production where earliness in flowering induction is sought after [48]. Apart from the temperature, the photoperiod and plant growth stage are also important for flowering initiation [47], while according to Pressman and Negbi [49], long days after a chilling period increase bolting incidence and flower stalk elongation. Leafy types are considered more sensitive to freezing temperatures, as well as heat and water stress conditions than root celery [35,36,39].…”

“…Propagation of plants is carried out by direct sowing of seeds (especially in the case of celeriac) or by transplanting after sowing in seed beds or seed trays. According to Baninasab [53], light exposure and temperatures higher than 20 • C and below 25 • C significantly increased germination rate and the percentage of germinated seeds of wild celery, indicating that soil temperature and exposure of seeds to light are crucial for plant propagation [47,48,54,55]. Seed germination may also be improved by thermal treatment (15 • C) and pre-sowing hydration of seeds followed by a slow drying process [56].…”