Organismic and environmental controls of bud growth in tropical trees.
Organismic and environmental controls of bud growth in tropical trees.
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热带树木芽生长的有机和环境控制。
DOI：
10.1079/9780851994475.0087
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
J. Crabbe
中科院分区：
文献类型：
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作者：
R. Borchert;J. Viémont;J. Crabbe
树木的生长几乎都是周期性的，而不是连续的。在热带和温带树木中，芽的生长期与芽的休眠期交替进行。在适应温带气候的木本植物中，已经发现了各种类型的休眠，这些植物的生长季节相对较短，温度和光照周期的年变化很大，这强烈地同步了营养和生殖树木的发育（图7.1A; crabb<s:1>， 1994年：表1；crabb<s:1>和Barnola， 1996年：图6.1）。在热带地区，月平均温度的变化通常小于1 - 2°C，光周期的年变化为1小时或更短（图7.2）。因此，气候季节性主要取决于旱季的持续时间和严重程度。例如，在哥斯达黎加瓜纳卡斯特的半落叶热带森林（这里讨论的大多数研究都是在那里进行的），在5-6个月的旱季中，年降水量通常不到5%（图7.2）。与冬季寒冷相比，严重的季节性干旱不会强烈地同步热带树木的周期性发育，在干旱季节营养芽或花芽断裂是常见的（图7.1B）。在热带森林中，树木的周期性发育甚至更不同步
Periodic rather than continuous growth is almost universal among trees. In tropical as in temperate trees periods of shoot growth (flushing) alternate with periods of bud rest or dormancy. Various types of dormancy have been identified in woody plants adapted to temperate climates with a relatively short growing season and large annual variations in temperature and photoperiod which strongly synchronize vegetative and reproductive tree development (Fig. 7.1A; Crabbé, 1994: Table 1; Crabbé and Barnola, 1996: Fig. 6.1). In the tropics monthly mean temperatures often vary by < 1–2°C and annual variation in photoperiod is 1 h or less (Fig. 7.2). Climatic seasonality is therefore mainly determined by duration and severity of the dry season. For example, in the semideciduous tropical forest of Guanacaste, Costa Rica, where most research to be discussed here was done, less than 5% of annual precipitation normally falls during the 5–6 month-long dry season (Fig. 7.2). In contrast with winter cold, severe seasonal drought does not strongly synchronize periodic development of tropical trees, and bud break in vegetative or flower buds during the dry season is common (Fig. 7.1B). Periodic tree development is even less synchronized in tropical forests with a short