title: Cd-Fe interactions: comparison of the effects of iron deficiency and cadmium on growth and photosynthetic performance in poplar.
abstract: To check the importance of Cd-induced iron deficiency in Cd stress, symptoms of Cd stress were compared with those of iron deficiency or the combination of these two stresses. Poplar plants grown in hydroponics with Fe-EDTA (e) or Fe-citrate (c) up to four-leaf stage were treated for two weeks either by the withdrawal of iron (Fedef), or supplying 10 μM Cd(NO3)2 in the presence (Cad) or absence of an iron source (Fedef + Cad). Cadmium and iron content of leaves developing under the stress was in the order of cCad > eCad > cFedef + Cad and cCad ≈ eFedef ≈ cFedef + Cad < eCad < cFedef, respectively. Growth inhibition was much stronger in Cad than Fedef plants. The inhibitory effects on CO2 fixation, maximal and actual efficiency of PSII, chlorophyll synthesis, as well as the stimulation of the accumulation of violaxanthin cycle components and increase in non-photochemical quenching were the strongest in cFedef+Cad plants, otherwise these parameters changed parallel to the iron deficiency of leaves. Tendency of changes in thylakoid composition were similar under Cad treatments and strong iron deficiency: particularly PSI and LHCII decreased. Therefore, the development of the photosynthetic apparatus under Cd stress was mainly influenced by the Cd-induced strong iron deficiency, while leaf growth was affected primarily by the presence of Cd.
authors.affiliation: Department of Plant Physiology and Molecular Plant Biology, Institute of Biology, Eötvös Loránd University, Budapest, Hungary. e_sarvari@ludens.elte.hu
authors.forename: Eva
authors.initials: E
authors.lastname: Sárvári
authors.forename: L
authors.initials: L
authors.lastname: Gáspár
authors.forename: A
authors.initials: A
authors.lastname: Solti
authors.forename: Ilona
authors.initials: I
authors.lastname: Mészáros
authors.forename: Gy
authors.initials: G
authors.lastname: Záray
authors.forename: F
authors.initials: F
authors.lastname: Fodor
mesh_terms: D002104:Cadmium / Q000378:metabolism*; D007501:Iron / Q000378:metabolism*; D010788:Photosynthesis; D018515:Plant Leaves / Q000254:growth & development* / Q000378:metabolism; D032107:Populus / Q000254:growth & development / Q000378:metabolism*
chemical_list: D002104:Cadmium; D007501:Iron