SULFIDE UTILIZATION AND INJURIES IN HYPOXIC ROOTS AND RHIZOMES OF COMMON REED (PHRAGMITES-AUSTRALIS)

The presented investigations have been carried out in order to estimat e toxic sulphide levels and to examine detoxification capabilities in roots and rhizomes of the common reed (Phragmites australis). Undergro und organs of common reed are sensitive towards sulphide above 1 mM ap plied exogenously under hypoxia. However, certain tolerance may be ach ieved by sulphide detoxification. Accumulated sulphide is partially us ed for the synthesis of npn-toxic thiols, mainly glutathione: But the detoxification capacity of the fw in roots and 300 underground organs is limited. Maximum concentrations of thiols are about 60 nmol/g(-1) n mol/g(-1) fw in rhizomes. Energy metabolism is considerably affected b y low sulphide concentrations of 1 mM for 4 days, and immediately dist urbed by increased concentrations up to 6 mM sulphide. Adenylate energ y charge, total adenylates, posthypoxic respiration, and fermentation capacity decrease significantly. Roots are more sensitive than rhizome s.