Perrin Magali, Rossi Sergio, Isabel Nathalie
Département des Sciences Fondamentales, Université du Québec à Chicoutimi, Chicoutimi, QC, Canada.
Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.
Tree Physiol. 2017 May 1;37(5):593-603. doi: 10.1093/treephys/tpx019.
Bud and cambial phenology represent the adaptation of species to the local environment that allows the growing season to be maximized while minimizing the risk of frost for the developing tissues. The temporal relationship between the apical and radial meristems can help in the understanding of tree growth as a whole process. The aim of this study was to compare cambial phenology in black spruce (Picea mariana (Mill.) B.S.P.) provenances classified as early and late bud flushing. The different phases of cambial phenology were assessed on wood microcores sampled weekly from April to October in 2014 and 2015 from 61 trees growing in a provenance trial in Quebec, Canada. Trees showing an early bud flush also exhibited early reactivation of xylem differentiation, although an average difference of 12 days for buds corresponded to small although significant differences of 4 days for xylem. Provenances with early bud flush had an early bud set and completed xylem formation earlier than late bud flush provenances. No significant difference in the period of xylem formation and total growth was observed between the flushing classes. Our results demonstrate that the ecotype differentiation of black spruce provenances represented by the phenological adaptation of buds to the local climate corresponds to specific growth dynamics of the xylem.
芽和形成层物候反映了物种对当地环境的适应性，这种适应性使得生长季节得以最大化，同时将发育中组织遭受霜冻的风险降至最低。顶端分生组织和径向分生组织之间的时间关系有助于从整体过程理解树木生长。本研究的目的是比较被归类为早芽萌动和晚芽萌动的黑云杉（Picea mariana (Mill.) B.S.P.）种源的形成层物候。在2014年和2015年4月至10月期间，每周从加拿大魁北克一个种源试验中生长的61棵树上采集木微芯，评估形成层物候的不同阶段。早芽萌动的树木也表现出木质部分化的早期重新激活，尽管芽的平均差异为12天对应于木质部的4天虽小但显著的差异。早芽萌动的种源比晚芽萌动的种源有更早的芽休眠，并更早完成木质部形成。在萌动类别之间，木质部形成期和总生长量没有观察到显著差异。我们的结果表明，以芽对当地气候的物候适应为代表的黑云杉种源的生态型分化对应于木质部特定的生长动态。
