Abstract:

The effects of anoxic sediment condition and light intensity on turion germination and sprout physiology of 〖WTBX〗Potamogeton crispus〖WTBZ〗 L.were studied.The anoxic condition of sediment was simulated by adding sucrose into sediment to stimulate the anaerobic mineralization of organic matters.The results showed that sediment anoxic condition reduced the accumulated turion germination rate of 〖WTBX〗Potamogeton crispus〖WTBZ〗 L.，low light intensity can enhance the inhibitory effect.However，low light intensity was favorable for predating the turion germination.Total chlorophyll (Chlt) and soluble protein(Pr)content of the sprouts increased up to the maximum(mean 250 and 1928mg/g FW) in the 01% addition treatment and then decreased with the increasing sediment anoxia，whereas the free amino acid(FAA) increased with the anxic level(up to 024 mg/g FW in the 10% addition treatment).However，low light intensity reduced the FAA content.The sediment anoxia had no significant effect on soluble carbohydrate(SC) content which whereas decreased with light intensity.The superoxide dismutase(SOD) activity increased with the sediment anoxia(in the control，01% and 05% addition treaments) then decreased down to the minimum in the 10% addition treatment.The peroxidases(POD) activity was kept declining with the anxic level.It was concluded that the turion germination of 〖WTBX〗P.crispus〖WTBZ〗 can be affected significantly by the sediment anoxia and the effects may be more important than that of the low light intensity.Slight sediment anoxia is favorable for physiology of the sprouts，but more severe sediment anoxia press the carbon/nitrogen balance and other physiological activities.Moreover，sediment anoxia and light intensity have significant influences on the antioxidative enzymes of the sprouts.

Key words: sediment anoxia/light availability/Potamogeton crispus   L./turion germination/physiology