Anfodillo Tommaso, Petit Giai, Sterck Frank, Lechthaler Silvia, Olson Mark E
Dipartimento Territorio e Sistemi Agro-Forestali, Università degli Studi di Padova Legnaro, Italy.
Forest Ecology and Forest Management Group, Wageningen University Wageningen, Netherlands.
Front Plant Sci. 2016 Nov 9;7:1681. doi: 10.3389/fpls.2016.01681. eCollection 2016.
The term "stress" is an important but vague term in plant biology. We show situations in which thinking in terms of "stress" is profitably replaced by quantifying distance from functionally optimal scaling relationships between plant parts. These relationships include, for example, the often-cited one between leaf area and sapwood area, which presumably reflects mutual dependence between sources and sink tissues and which scales positively within individuals and across species. These relationships seem to be so basic to plant functioning that they are favored by selection across nearly all plant lineages. Within a species or population, individuals that are far from the common scaling patterns are thus expected to perform negatively. For instance, "too little" leaf area (e.g., due to herbivory or disease) per unit of active stem mass would be expected to incur to low carbon income per respiratory cost and thus lead to lower growth. We present a framework that allows quantitative study of phenomena traditionally assigned to "stress," without need for recourse to this term. Our approach contrasts with traditional approaches for studying "stress," e.g., revealing that small "stressed" plants likely are in fact well suited to local conditions. We thus offer a quantitative perspective to the study of phenomena often referred to under such terms as "stress," plasticity, adaptation, and acclimation.
“胁迫”一词在植物生物学中很重要，但含义模糊。我们展示了一些情况，即在这些情况下，用“胁迫”来思考可通过量化植物各部分之间功能最优比例关系的偏离程度而得到有益替代。这些关系包括，例如，叶面积与边材面积之间常被提及的关系，这大概反映了源组织和库组织之间的相互依赖，并且在个体内部和物种之间呈正相关。这些关系似乎对植物功能至关重要，以至于在几乎所有植物谱系中都受到选择青睐。因此，在一个物种或种群内，偏离常见比例模式的个体预计表现较差。例如，每单位活性茎质量的叶面积“过少”（如由于食草作用或疾病）预计会导致每呼吸成本的碳收入较低，从而导致生长减缓。我们提出了一个框架，该框架允许对传统上归因于“胁迫”的现象进行定量研究，而无需诉诸该术语。我们的方法与研究“胁迫”的传统方法形成对比，例如，揭示小型“受胁迫”植物实际上可能非常适合当地条件。因此，我们为研究常被用“胁迫”“可塑性”“适应性”和“驯化”等术语提及的现象提供了一个定量视角。
