Urabe, J. Kyoto University, urabe@ecology.kyoto-u.ac.jp
Sterner, R. University of Minnesota, stern007@maroon.tc.umn.edu

To examine if responses of life history traits to differences in food quality is the same as differences in food quantity, Daphnia obtusa were reared individually with food (Scenedesumus acutus) of different C:N:P ratio. Food conditions examined were 1 mgC/l of N and P rich algae (H-MON: C:N:P=110:16:1), 1 mgC/l of N deficient algae (H-LON: 270:18:1), 1 mgC /l of P deficient algae (H-LOP: 1100:100:1) and 0.2 mgC/l of N and P rich algae (L-MON). Daphnia fed on H-LON and H-LOP showed longer maturation time, smaller maturation size and smaller brood size than those fed on H-MON. Such response was similar to those fed on L-MON. Compared with Daphnia fed on L-MON, however, those fed on LON and LOP showed higher body growth rate after maturation. In addition, Daphnia fed on LON and LOP produced smaller eggs with lower amount of yolk. Furthermore, 40-60% of eggs produced by Daphnia fed on LON and LOP failed to develop normally and were aborted. These results demonstrate that life history was quite different between Daphnia fed on small quantity of high quality food and large quality of low quality food.
Day: Tuesday, Feb. 2
Time: Poster
Location: Sweeney Center
Code: SS49TU1363S