EFFECTS OF BULB STORAGE TEMPERATURES AND DURATION ON THE FLOWERING OFNARCISSUS-TAZETTA VAR CHINENSIS

The effects of various storage temperatures on Narcissus bulbs and the ir duration of storage on the initiation and development of flower bud s were investigated. Special attention was paid to the retardation of flowering. 1. The development of flower buds progressed most rapidly a t 20 degrees C, followed by 25 degrees or 15 degrees C and 30 degrees C. For bulbs stored at 15 degrees or 20 degrees C, the mean flowering date was earlier, but flowering percentage and the number of florets w ere smaller than in those at 25 degrees C, whereas bulb storage at 30 degrees C delayed flowering. Therefore, a temperature of 25 degrees C was considered to be optimal for storage. 2. The temperature range bet ween 15 degrees and 20 degrees C was optimum for the development of fl ower buds between the carpel formation stage and flowering. At 25 degr ees C flower buds ceased to develop and became blasted. 3. Flowering w as retarded when bulbs were transferred to 5 degrees or 10 degrees C a nd stored for up to 11 months. After cold storage, bulbs should be kep t at 30 degrees C for 3 weeks to initiate flower buds and then at 25 d egrees C for 12 weeks to promote further development; thereafter they should be grown at 15 degrees similar to 20 degrees C.