Search Results

You are looking at 1 - 3 of 3 items for

  • Author or Editor: Bruce R. MacKay x
Clear All Modify Search

Vernalization and growing degree-day requirements of Thalictrum delavayi `Hewitt's Double' were determined to improve the production scheduling of this cut flower crop. Two-year-old crowns of T. delavayi `Hewitt's Double', lifted in the fall, were exposed to cold storage for 0, 3, 6, 9, 12, or 15 weeks at 8 ± 1°C. After storage, the containerized plants were grown at Massey Univ., Palmerston North (40°20.S) in a greenhouse heated at 15°C and vented at 20°C, under a natural photoperiod (11 h increasing to 13 h) plus a 4-h night interruption between 2200 and 0200 HR. As buds continued to develop during storage at 8°C, growing degree-days calculations were made over both storage and greenhouse forcing periods. All plants flowered, but T. delavayi `Hewitt's Double' nevertheless showed a quantitative vernalization requirement, being fully saturated after 6 weeks of cold storage at 8°C. With a base temperature of 0°C, time to flowering reduced from 3338 degree-days without vernalization to an average 2804 degree-days subsequent to the saturation of the vernalization response (6 to 15 weeks of vernalization). Flower yield averaged between three and five stems per plant, with stem lengths ranging between 140 and 200 cm. Differences in flower yield and quality among storage durations were minor and not commercially significant.

Free access

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.

Free access

Major reform of the undergraduate degree program in the Faculty of Agricultural and Horticultural Sciences at Massey University has resulted in greater emphasis being placed on developing attributes of lifelong learning in our students. Translating this particular goal into transparent educational practice in the horticulture courses required us to overturn the existing teaching paradigm. The traditional content-focused, principles first, integration second strategy of the existing horticulture curriculum was replaced at the 100 level by a new course that melded the discipline of horticulture with attributes needed for lifelong learning. Using action learning strategies, principles of horticulture were presented in context, with students encouraged to apply and analyze them in the wholeness of the discipline. Students critically reflected on their experiences through writing-to-learn exercises, class or group discussion, oral presentations, and experientially through their laboratories. By incorporating our students' experiences with these strategies, we successfully achieved our goal of the students' learning and relating theprinciples of horticulture to the whole discipline. Although the students understood our goals in engaging them in writing-to-learn and group activities, they did not appear to recognize the educational processes in which they participated throughout the course. It seems that in forming the foundation for lifelong learning in applied science, greater attention must be given to making our mental models of the education process more transparent to the students.

Full access