Manipulation of bolting and flowering in celery (Apium graveolens L. var. dulce). I. Effects of chilling during germination and seed development

SummaryChilling imbibed seeds of celery cv. New Dwarf White for six and eight weeks at 5°C induced flowering subsequently at a minimum glasshouse temperature of 15°C in ca. 50% of the treated plants. The longer chilling treatment induced flowering at a lower leaf number. Promotion of flowering by chilling imbibed seed was only apparent when plants were subsequently grown in a glasshouse at a minimum temperature of 15°C. Complete devernalization occurred when plants raised from chilled imbibed seed were grown at a minimum temperature of 20°C. These plants then initiated leaves normally without any flowering or bolting. Cv. Celebrity showed no vernalization response when chilled as imbibed seed. Chilling seed at different stages of development on the mother plant for four and eight weeks at 5°C in a growth room proved to be ineffective in vernalizing the progeny. Low-temperature treatments applied in growth rooms during seed production decreased the percentage both of seeds germinating and of seedlings emer...