Novoplansky Ariel
Mitrani Department of Desert Ecology, Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Midreshet Sede-Boker 84990, Israel.
New Phytol. 2003 Oct;160(1):111-118. doi: 10.1046/j.1469-8137.2003.00871.x.
• The performance of the whole plant is largely dependent on its ability to allocate limited resources to branches that perform best throughout its life. Here, the hypothesis that the fate of young branches is determined by their growth rates and not merely by their relative physical sizes or net photosynthetic outputs was tested. • The development of asymmetrical two-branch plants was followed after either one or both of the branches were restrained for short periods. • The larger branch was invariably dominant in unrestrained or bilaterally restrained plants. However, when the larger branch was restrained while the smaller branch was not, the branch hierarchy inverted despite the pronounced photosynthetic advantage of the larger branch over its smaller counterpart. • It is suggested that growth rates are more important than physical size or photosynthetic output in young plants, where they could serve as better predictors of the overall future performance of the branch. It is speculated that rate-sensitivity has been selected for when plastic responses cannot adequately track environmental changes in real time.
• 整株植物的表现很大程度上取决于其将有限资源分配给在其整个生命周期中表现最佳的枝条的能力。在此，对幼嫩枝条的命运由其生长速率决定而非仅仅由其相对物理大小或净光合产量决定这一假设进行了测试。
• 在一个或两个枝条被短期抑制后，观察不对称双枝植物的发育情况。
• 在未受抑制或双侧受抑制的植物中，较大的枝条总是占主导地位。然而，当较大的枝条被抑制而较小的枝条未被抑制时，尽管较大的枝条相对于较小的枝条具有明显的光合优势，但枝条等级却颠倒了。
• 这表明在幼嫩植物中，生长速率比物理大小或光合产量更重要，在幼嫩植物中，生长速率可以更好地预测枝条未来的整体表现。据推测，当可塑性反应不能充分实时跟踪环境变化时，速率敏感性就会被选择出来。
