Studies on the flower bud differentiation and development in freesia

Abstract

1. There are some opinions not coincident in re-lation to the method of forcing, especially on the time and the method of low temperature treatment in freesia. Therefore, these experiments were con-ducted to find out the effects of low temperature upon the flower bud formation and flowering in the plant. 2. The materials used were the corms of F. refracta var. alba, which were transported from Ha-chijio Island. 3. The corms of the plant were divided into two groups; one (A) had no treatment before they were planted on every 3 rd day of the month from August to December, and the other (B) had cold storage, which comprised various methods of low tempera-ture treatment by plots, before they were planted. 4. In the plots of group A, the flower bud for-mation occurred from October 24 to December 23, when the average minimum temperatures of 10 days of the months were 2°C to 10°C. and the height of the plants were 3.1 to 22.8cm, according to the planting time. 5. The flowers began to bloom from January 23 to March 16 according to the planting time. And the percentage of flowering, number of flowers per plant, height of plants, number of leaves were all reduced, the percentage of malformed flower were increased and the term of harvest prolonged, as the plants were planted later. 6. In the plots of group B, the flower bud initia-tion occurred from September 14 to November 3, when the height of plants were 13. 1 to 23.6cm, and the flowers began to bloom from December 1 to February 6, according to treatments. 7. The most superior treatment in the time of flower bud initiation and flowering was 10°C for 50 days wet storage, and the next was 10°C for 40 days wet storage. But the percentage of flowering, num-ber of flowers per plant, height of plants, number of leaves were less and the term of harvest prolong-ed more than the other treatments. And the other four treatments; 3°C for 30 days dry storage, 15°C for 30 days dry storage, 10°C for 20 days wet sto-rage, and 10°C for 20 days then 3°C for 20 days wet storage, did not hasten the time of flowering as the plants of group A.