Direct Demonstration of Nectar Reabsorption in the Flowers of Grevillea robusta (Proteaceae)
Автор антэкологических публикаций
, 1995. V. 9. No. 4. P. 584–588 (5).
1. The question of whether flowers reabsorb nectar was investigated in Grevillea robusta (Proteaceae), which bears large inflorescences with copious dilute nectar exposed to the atmosphere. 2. Each flower secreted nectar for 2 days and secretion rates were strongly dependent on temperature. 3. Reabsorption of nectar was shown indirectly, as has been done for other species, by comparing the accumulated nectar (standing crop) with the much greater cumulative rate of secretion measured during repeated sampling. 4. Experimental manipulation of nectar volumes and concentrations permitted the direct demonstration of nectar reabsorption under field conditions, shown by a decrease in sugar content of overfilled flowers. This occurred from both a high volume and a high concentration. 5. The results indicate active regulation of nectar sugar content by the flowers, with a balance between secretion, evaporation and reabsorption.