Zizania aquatica

Rooted aquatic plants, such as wild rice (Zizania aquatica), can accumulate up to 67 mg Pb/kg dry weight when cultured in tanks contaminated with high concentrations of powdered lead (equivalent to 7400 kg Pb/ha) however, this level is not considered hazardous to waterfowl feeding on wild rice (Behan et al. 1979). Lead content in plants collected from heavily hunted areas near refuges did not differ from those collected in the protected areas (Behan et al. 1979), which suggests that lead bioavailability to rooted aquatics is substantially lower from shot than from powdered lead. 

Seeds of many terrestrial species which fail to germinate below water quickly lose their viability when maintained under these conditions. Quite the opposite is the case with wild rice Zizania aquatica) however. Here, air drying of the grains for 90 days causes loss of viability, whereas after-ripening at low temperatures in stagnant water actually accelerates their subsequent rate of germination [116]. This represents an adaptation to habitat, for the grains of this particular wild rice... 

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