How plants cope with water stress in the field.: Photosynthesis and growth
How plants cope with water stress in the field.: Photosynthesis and growth
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DOI：
10.1093/aob/mcf105
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发表时间：
2002-06-01
期刊：
影响因子：
4.2
通讯作者：
Pinheiro, C
中科院分区：
文献类型：
--
作者：
Chaves, MM;Pereira, JS;Pinheiro, C
植物在其生命周期中经常遭受土壤和大气水分亏缺的时期。今后，即使在今天的干旱/半干旱地区以外，这种现象的发生频率也可能增加。植物缺水的反应是复杂的，涉及有害的和/或适应性的变化，并在现场条件下，这些反应可以协同或拮抗修改叠加的其他压力。这种复杂性说明使用的例子，木本和草本植物的物种主要是从地中海型生态系统，从避免干旱的策略，如在冬季/春季的一年生植物或在深根多年生植物，硬叶植物的抗逆性。物种之间的差异，可以追溯到不同的能力，水收购，而不是在一个给定的水状态的新陈代谢的差异，进行了说明。根的变化：成苗率或茎中储备的暂时积累伴随着氮和碳代谢的改变，其精细调节在很大程度上仍然未知。在叶水平上，激发能通过光合C代谢以外的过程耗散是水分胁迫条件下的重要防御机制，并伴随着光化学的下调，从长远来看，碳代谢。(C)2002年《植物学年鉴》（Annals of Botany Company）
Plants are often subjected to periods of soil and atmospheric water deficit during their life cycle. The frequency of such phenomena is likely to increase in the future even outside today's arid/semi-arid regions. Plant responses to water scarcity are complex, involving deleterious and/or adaptive changes, and under field conditions these responses can be synergistically or antagonistically modified by the superimposition of other stresses. This complexity is illustrated using examples of woody and herbaceous species mostly from Mediterranean-type ecosystems, with strategies ranging from drought-avoidance, as in winter/spring annuals or in deep-rooted perennials, to the stress resistance of sclerophylls. Differences among species that can be traced to different capacities for water acquisition, rather than to differences in metabolism at a given water status, are described. Changes in the root : shoot ratio or the temporary accumulation of reserves in the stem are accompanied by alterations in nitrogen and carbon metabolism, the fine regulation of which is still largely unknown. At the leaf level, the dissipation of excitation energy through processes other than photosynthetic C-metabolism is an important defence mechanism under conditions of water stress and is accompanied by down-regulation of photochemistry and, in the longer term, of carbon metabolism. (C) 2002 Annals of Botany Company.