Cut Flower Quality Exposed to Sudden Abnormal Temperature During Long Term Storage of Lily Bulbs

The objective of this study was to investigate the effect of artificially low time/temperature treatments during normal bulb storage at -1.5 degrees C on quality of cut flowers of Oriental hybrid lily. Lily bulbs harvested in autumn were stored for up to 8 months at -1.5 degrees C to study the feasibility of providing quality cut flower production year-round. However, occasional mechanical breakdown problems to conventional low temperature storage rooms can affect quality of bulbs exposed to abnormal low and/or high temperatures that can follow such breakdowns. Bulbs of the oriental hybrid lily 'Casa Blanca' bulbs were exposed to -3, -5, 15, 20 degrees C for 3, 5, 7 d, respectively, on 30 March. and 30 May. The critical threshold duration at given temperatures that affected bulb quality was 7 d at -3 degrees C, 3 d at -5 degrees C, 7 d at 15 degrees C and 5 d at 20 degrees C. Growth and flowering was inversely affected as the duration at these abnormal temperatures increased and growth inhibition, death of plants, and leaf malformation was observed when flowers were forced.