冷蔵期間が促成ボタンの生育及び切花品質に及ぼす影響

Abstract

The present study was undertaken to establish forcing system for tree paeony. First, the flower bud differentiation and development in tree paeony (Paeonia suffruticosa Ardr. cv.′Hanakisoi′) was observed, and secondly the effects of the duration of cold storage on the flowering time and quality of cut flowers of forced tree paeony were investigated.1. The differentiation of leaves had already finished and the differentiation of petals had begun on Aug. 27. Stamens in a few sample plants and pistils in the majority of sample plants were going to form on Sept 27 and Oct. 18 respectively.2. As the storage at 0°C was prolonged, the sprouting and flowering became earlier. However, the number of days and cumulative temperature from sprouting to flowering differed little with the duration of 3 cold storage within 5 to 7 weeks.3. The flowering percentage was highest after 5 week storage and lowest after 7-week storage.4. The weight of cut flower and the number of petals did not differ significantly with the storage duration. However, the flower diameter was increased and the leaf area decreased with shortening the duration of cold storage. And especially, the development of lower leaves tended to be suppressed.5. Cut flowers looked well-balanced and were superior in figure after the trees were chilled during 6 to 7 weeks.These results show that the stage of flower bud development before cold storage and the temperature and duration of cold storage have a great influence on the flowering time, flowering percentage and the quality of cut flowers of forced tree paeony.