Southwick A K, Southwick E E
Biological Station, University of Michigan, 49769, Pellston, MI, USA.
Oecologia. 1983 Jan;56(1):121-125. doi: 10.1007/BF00378227.
In common milkweed (Asclepias syriaca), flower nectar volumes, concentration and sugar production varied according to the age of the sampled blossoms. In individual blossoms, nectar production peaked daily at 0800 hr. Peak production during the life of the flower occurred on the second day of flowering, 50 h after anthesis, and nectar production ceased after 120 h. The amount and quality of nectar were affected by microclimatic conditions and varied between clones. However, the same secretory patterns were found in all flowers studied. This age dependent nectar secretion combined with the sequential mode of flowering found on a single stem, results in substantial reward for extended periods to nectar feeders.
在普通马利筋（乳草属植物）中，花蜜的体积、浓度和糖分产量会根据所采花朵的年龄而有所不同。在单朵花中，花蜜产量在每天08:00达到峰值。花朵一生中的产量峰值出现在开花的第二天，即开花后50小时，120小时后花蜜分泌停止。花蜜的数量和质量受微气候条件影响，且在不同克隆体之间存在差异。然而，在所有研究的花朵中都发现了相同的分泌模式。这种与年龄相关的花蜜分泌，加上在单个茎干上发现的连续开花模式，使得花蜜采集者在较长时间内都能获得可观的回报。
