Key message

In Sakhalin fir trees from nine different source elevation provenances, we found genetic differentiation of traits related to mechanical reinforcement, hydraulic efficiency, and photosynthetic capacity.

Abstract

Climatic conditions change with elevation and trees must cope with the resulting variation in stresses. Thus, trees may differentiate into elevational ecotypes with genetic-based variations in morphological and physiological traits. To explore genetically differentiated traits related to elevational adaptation, needles and stems were analyzed in 43-year-old Sakhalin fir [Abies sachalinensis (Fr. Schm.) Masters] trees which derived from nine source elevations (230–1250 m above sea level) and grown in a nursery plantation at 230 m above sea level. Trees from a high-elevation provenance showed greater mechanical reinforcement in needles and stems. Needles from high-elevation provenances were shorter and thicker, and developed more sclerenchyma in transfusion tissue. Shorter and thicker stems and larger reaction wood portions were also found. Moreover, needles and stems from high-elevation provenance trees also exhibited xylem traits associated with higher hydraulic efficiency and lower hydraulic safety. In the midrib xylem, the theoretical conductivity was greater due to higher number of tracheids. Pit architecture of stem-xylem tracheid indicated a higher hydraulic efficiency, but lower hydraulic safety due to larger pit apertures. Furthermore, high-elevation provenance trees exhibited a thicker bark, which may reduce water losses and act as a water reservoir in winter. Leaf nitrogen content and stomata number per needle were higher in high-elevation provenance trees, both of which were related to high photosynthetic capacity. Overall, the data suggested genetic differentiation of traits related to various trade-offs and optimization for mechanical resistance, hydraulic efficiency, and photosynthetic capacity at high elevation in Sakhalin fir.

中文翻译：

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萨哈林冷杉（Abies sachalinensis）对形态和解剖性状的早期适应。

关键信息

在来自九个不同来源海拔高度的萨哈林州杉树中，我们发现了与机械增强，水力效率和光合能力相关的性状的遗传分化。

抽象

气候条件随海拔的升高而变化，树木必须应对由此产生的压力变化。因此，树木的形态和生理特征可能会因遗传变异而分化为海拔生态型。为了探索与海拔高度适应相关的遗传分化性状，对43岁的萨哈林冷杉[ Abies sachalinensis]的针和茎进行了分析。（Fr. Schm。）（大师）]源自9个海拔高度（海拔230–1250 m）并生长在海拔230 m的苗圃中的树木。高海拔来源的树木在针和茎上显示出更大的机械增强作用。来自高海拔种源的针头越来越短，越来越粗，在输血组织中形成了更多的硬化。还发现茎短而粗，反应木部分更大。此外，高海拔种源树的针叶和茎还表现出木质部特征，与较高的水力效率和较低的水力安全性有关。在中肋木质部中，由于较高的气管数量，理论电导率更高。茎-木质部气管的坑结构表明较高的水力效率，但由于较大的坑孔而降低了水力安全性。此外，高海拔种树的树皮较厚，可以减少水的流失并在冬季充当蓄水库。高海拔种源树的叶片氮含量和每针气孔数较高，这都与高光合能力有关。总体而言，数据表明与萨哈林冷杉高海拔地区的各种折衷有关的性状的遗传分化和机械阻力，水力效率和光合能力的优化。