Physiological and morphological effects of cadmium chloride, sodium chloride and their combinations in Ceratophyllum demersum L.

ABSTRACTPhD THESISPHYSIOLOGICAL AND MORPHOLOGICAL EFFECTS OF CADMIUMCHLORIDE, SODIUM CHLORIDE AND THEIR COMBINATIONS INCeratophyllum demersum L.Muhittin DOĞANUNIVERSITY OF ÇUKUROVAINSTITUTE OF NATURAL AND APPLIED SCIENCESDEPARTMENT OF BIOLOGYSupervisor: Assoc. Prof. Dr. Saadet SAYGIDEĞERYear: 2005, Page: 137Jury: Assoc. Prof. Dr. Saadet SAYGIDEĞERProf. Dr. Cengiz DARICIProf. Dr. Ferit KARGINAssoc. Prof. Dr. Elman İSKENDERAssoc. Prof. Dr. Levent ÖZTÜRKIn this study, some physiological and morphological changes were investigated inCeratophyllum demersum L. which is treated with different concentrations of Cd (0, 0.01, 0.1 and 1mg L-1) and NaCl (0, 20, 40 and 80 mM) and their combinations (0, 0.01+20, 0.1+40 and 1+80 mg L-1+ mM) during 96 hours.At low concentrations of Cd, NaCl and Cd+NaCl, considerable morphological changes didnot occur but leaf shedding and partial tissue softening were observed at high concentrations. In themacrophytes treated with 0, 0.01, 0.1 and 1 mg Cd L-1, Cd concentrations increased 15.4, 33.5 and160.0 fold, respectively, compared to control. On the otherhand, increase in Cd amount was found14.4 and 28.1 fold at 0.01+20 and 0.1+40 Cd+NaCl combinations, respectively. In the macrophyteapplied with individal NaCl at 80 mM concentration, Na concentration increased 2.31 fold and at0.1+40 Cd+NaCl treatment caused 1.92 fold increased. However, Cd and Na concentrations followingCd+NaCl application showed decreases when compared to individal Cd and NaCl treatments. It wasfound that micro- and macro-nutrient concentrations of macrophyte were affected by Cd and NaCl.Although macro-nutrient K concentrations increased by 49%-132% in the effect of Cd, decline wasdetermined after NaCl and Cd+NaCl treatments. P and N concentrations were determined to reducefollowing all three applications. Following Cd and NaCl applications micro-nutrient Mn increased,however, decrease was found in Cu and Zn concentrations of macrophyte tissues. There was nosignificant changes in Fe concentration of macrophyte tissues. Applied stress factors causedsignificant decline in chlorophyll-a and chlorophyll-b contents at high concentrations. In carotenoidcontent, however, no considerable change occured. Cd, NaCl and their combinations especially athigh concentrations caused decrease in total soluble carbohydrate and glucose amounts. Determinedincreases in the amounts of proline and cysteine aminoacids indicate their roles in response to Cd andNaCl toxicities. The maximum increases in reduced ascorbate contents were determined as 72%, 82%and 92% at concentrations of 1 mg Cd L-1, 40 mM NaCl and 0.1+40 mg L-1 + mM combination,respectively. On the otherhand, observed increases in lipid peroxidation show that oxidative damageoccurred in membranes resulting from Cd and NaCl stresses.Key words: Ceratophyllum demersum L., cadmium stress, NaCl stress, interaction, physiological andmorphological changes.II