2005 Volume 68 Issue 5 Pages 705-708
Leaves size in longitudinal and transverse direction of dandelion (Taraxacum officinale Weber.) were measured in every two days after removal of whole above ground organs at natural day length and at dark conditions in pots culture. Area and dry weight of each leaf was estimated non-destructively by using allometric relations, which were made from sampling leaves. The light condition caused differences in re-growth of dandelions between at natural day length and at dark condition. Light-photosynthesis curve revealed that light saturated productivity of leaves was about 13.0 CO2 μmol/m²/sec. and that respiration rate as 0.49 CO2 μmol/m²/sec. Quantity balance of photosynthetic production was estimated for each leaf in every day. New leaf grew rapidly and reached the maximum size in 10 days after emergence. Surplus production kept nearly balanced zero throughout this period. The balance became surplus after leaf completed the growth. Production economy during the early stage in each leaf was a self-supporting process without depending source on other organs. A leaf got about 0.3g dry weight surplus production during the life span. It is considered that these characteristics of dandelion adapted to the grassland that disturbed frequently by mowing or trampling.
