Shitaka Y, Hirose T
Biological Institute, Faculty of Science, Tohoku University, Aoba, 980, Sendai, Japan.
Oecologia. 1993 Sep;95(3):334-339. doi: 10.1007/BF00320985.
The effect of different dates of germination on the timing of flowering and the final reproductive yield was examined in a short-day annual plant Xanthium canadense (cocklebur). Delays in germination of 30 and 60 days deferred flower initiation by 2 and 9 days, respectively. Although plants that germinated later were smaller because of the shorter growing period, the reproductive yields did not show as much reduction as the vegetative biomass. The reproductive effort (RE, defined as the ratio of final reproductive yield to the vegetative biomass at the end of the growing season) increased 1.5 and 2.5 times with delays in germination of 30 and 60 days, respectively. A simple model of plant growth was used to analyse the factors involved in the control of RE, which depends only on the dry mass productivity and its partitioning in the reproductive phase, and is independent of the productivity and partitioning in the vegetative phase. Since relative allocation of dry mass to the reproductive part in the reproductive phase was similar for plants with different germination dates, the different REs could be ascribed mainly to differences in productivity of the vegetative parts in the reproductive period. The dependence of RE on plant size is discussed.
在短日照一年生植物加拿大苍耳中，研究了不同发芽日期对开花时间和最终繁殖产量的影响。发芽延迟30天和60天分别使开花起始推迟2天和9天。尽管后期发芽的植株因生长周期较短而较小，但繁殖产量的降低幅度不如营养生物量那么大。随着发芽延迟30天和60天，繁殖投入（RE，定义为生长季末最终繁殖产量与营养生物量之比）分别增加了1.5倍和2.5倍。使用一个简单的植物生长模型来分析控制繁殖投入所涉及的因素，繁殖投入仅取决于生殖阶段的干物质生产力及其分配，而与营养阶段的生产力和分配无关。由于不同发芽日期的植株在生殖阶段干物质向生殖部分的相对分配相似，不同的繁殖投入主要可归因于生殖期营养部分生产力的差异。文中还讨论了繁殖投入对植株大小的依赖性。
