Vernalization and Growing Degree-day Requirements for Flowering of Thalictrum delavayi `Hewitt's Double'

• Published in: HortScience Vol. 34; no. 1; pp. 59 - 61
• Main Authors: Huang, Ning, Funnell, Keith A, MacKay, Bruce R
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Alexandria, VA American Society for Horticultural Science 01.02.1999
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Biology and morphogenesis of the reproductive apparatus. Photoperiodism, vernalisation; Economic plant physiology; Flowering, floral biology, reproduction patterns; Fundamental and applied biological sciences. Psychology; Growth and development; Plant physiology and development; Vegetative and sexual reproduction, floral biology, fructification; Temperature; Cold; Ranunculaceae; Ornamental crop; Environmental factor; Requirement; Induced flowering; Storage; Dicotyledones; Vernalization; Angiospermae; Flowering; Spermatophyta
• ISSN: 0018-5345; 2327-9834
• DOI: 10.21273/HORTSCI.34.1.59

Vernalization and growing degree-day (GDD) requirements of Thalictrum delavayi Franch. `Hewitt's Double' were investigated by exposing crowns to cold storage for 0, 3, 6, 9, 12, or 15 weeks at 8 °C, and subsequently planting in a heated greenhouse under long-day conditions. Cumulative vernalization of crowns was complete after 6 weeks of cold storage at 8 °C. The time to flower, including time at 8 °C, was 3338 GDD (base temperature of 0 °C) without vernalization and 2802 GDD after complete vernalization. Commercial recommendations for rapid and predictable flowering of T. delavayi `Hewitt's Double' should include cold storage of crowns for a minimum of 6 weeks at 8 °C as part of the 2802 GDD during vernalization and forcing.