2011-05-10 (火) 10:30
(Room: A809 )
Cost of reproduction and compensative responses for reproduction in Gagea lutea
Cost of reproduction in perennial plants highly depends on the type of resource budget.
Compensation of reproductive cost by the photosynthesis of reproductive organs has also been reported in many studies.
Furthermore, photosynthetic carbon gain often varies during a reproductive period, indicating that resource availability for reproduction may also vary within a reproductive period if current photosynthetic products are used for fruit development.
Using Gagea lutea as the focal species, we assessed cost of reproduction and compensative responses by examining the changes in bulb size, leaf longevity and carbon accumulation per plant during a whole growth season among reproductive intact, flower removal, and vegetative plants.
Bulb growth was negatively influenced by flower production and fruit production, indicating a trade-off between current reproduction and future growth.
The removal of bract significantly reduced seed production, while removal of basal leaf did not influence seed production so much.
This indicates the importance of current photosynthesis by the bract for seed production.
In addition, fruit-producing plants extended leaf longevity resulting in more carbon fixation compared to plants without fruits.
Such a compensative response may reduce the cost of reproduction in this species.