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キーワード:
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要旨:
Carbohydrates provide the building blocks for plant structures as well as versatile resources for
metabolic processes. The nonstructural carbohydrates (NSC), mainly sugars and starch, fulfil
distinct functional roles, including transport, energy metabolism and osmoregulation, and
provide substrates for the synthesis of defence compounds or exchange with symbionts involved
in nutrient acquisition or defence. At the whole-plant level, NSC storage buffers the asynchrony
of supply and demand on diel, seasonal or decadal temporal scales and across plant organs.
Despite its central role in plant function and in stand-level carbon cycling, our understanding of
storage dynamics, its controls and response to environmental stresses is very limited, even after a
century of research. This reflects the fact that often storage is defined by what we can measure,
that is, NSC concentrations, and the interpretation of these as a proxy for a single function,
storage, rather than the outcome of a range of NSC source and sink functions.Newisotopic tools
allow direct quantification of timescales involved in NSC dynamics, and show that NSC-C fixed
years to decades previously is used to support tree functions. Here we review recent advances,
with emphasis on the context of the interactions between NSC, drought and tree mortality.
