The physiological mechanism(s) of needle abscission resistance in root detached balsam fir

香脂杉根离体抗针脱落的生理机制

• 批准号: 364061-2007
• 负责人: Lada, Rajasekaran
• 金额: $ 3.03万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=528110
• 关键词: physiological; mechanism; needle; abscission; resistance

Needle loss in Balsam fir threatens the survival of the 97 million dollar Atlantic Canada Christmas Tree and Greenery industry. The exact cause of needle drop is not known. Clones with high needle abscission resistance are yet to be identified and developed. The anatomical, physiological mechanisms of needle abscission resistance in root detached (RD) Balsam fir are yet to be uncovered. The initiators, the signals and the modulators of needle abscission are also not known. This project will identify the clones with enhanced needle abscission resistance and discover the initiators, signals and the mechanism and the modulators of needle abscission and regulation. We propose that needle drop in RD Balsam fir is initiated by multiple stresses (dehydration, mechanical and extreme temperatures), triggering complex yet unknown cellular signals, involving multiple plant hormones and/or certain volatiles, promoting a cascade of senescence reactions, resulting in dissolution of certain cell wall components at the point of attachment, promoting abscission. This project will lead to several discoveries relating to causal factor, signals, needle abscission physiology and needle abscission resistance mechanism(s) of RD Balsam fir. An understanding of these processes will help to screen and identify the genotypes with enhanced needle abscission resistance and develop technologies to control needle loss contributing directly to the sustainability of the Christmas tree industry to retain its competitive position and contribute to Canadian bioeconomy and human resource development.

香脂冷杉的针叶损失威胁着价值 9700 万美元的加拿大大西洋地区圣诞树和绿化产业的生存。针掉落的确切原因尚不清楚。具有高抗针脱落性的克隆尚待鉴定和开发。根离体（RD）香脂冷杉抵抗针脱落的解剖学和生理机制尚未被揭示。针脱落的引发剂、信号和调节剂也是未知的。该项目将鉴定具有增强针脱落抗性的克隆，并发现针脱落和调控的启动子、信号以及机制和调节剂。我们认为，RD 香脂冷杉中的针头掉落是由多种应力（脱水、机械和极端温度）引发的，触发复杂但未知的细胞信号，涉及多种植物激素和/或某些挥发物，促进一系列衰老反应，导致附着点某些细胞壁成分溶解，促进脱落。该项目将带来与 RD 香脂冷杉的因果因素、信号、针脱落生理学和针脱落抵抗机制相关的多项发现。了解这些过程将有助于筛选和识别具有增强针脱落抵抗力的基因型，并开发控制针脱落的技术，直接有助于圣诞树行业的可持续性，以保持其竞争地位，并为加拿大生物经济和人力资源开发做出贡献。