title: [Influence of different concentration Ni and Cu on the photosynthesis and chlorophyll fluorescence characteristics of Peganum harmala].
abstract: A pot experiment was conducted to study the influence of different concentration (0, 50, 100, 200, and 400 mg kg(-1)) Ni and Cu on the growth, photosynthesis, and chlorophyll fluorescence characteristics of Peganum harmala seedlings. With increasing concentration Ni in the medium, the seedlings growth parameters, photosynthetic pigment content, net photosynthetic rate (P(n)), stomatal conductance (G(s)), transpiration rate (T(r)), maximal photochemical efficiency of PS II (F(v)/F(m)), quantum efficiency of electric transport of PS II (phi (PS II)), and coefficient of photochemical quenching (q(P)) of P. harmala decreased significantly, while the intercellular CO2 concentration (C(i)) and the coefficient of non-photochemical quenching (q(N)) were in adverse. The decrease of P(n) under Ni stress was mainly caused by non-stomatal limitation. At 50 mg kg(-1) Cu, the growth parameters, photosynthetic pigment content, P(n), G(s), T(r), C(i), F(v)/F(m), phi(PS II), and q(P) reached their peak values; at 100 mg kg(-1) Cu, the growth parameters, chlorophyll a and b contents, P(n), G(s), T(r), C(i), and F(v)/F(m) were still slightly higher than the control; while with the further increasing Cu concentration in the medium, all the test indices except q(N) tended to decrease. The decrease of P(n) under Cu stress was mainly caused by stomatal limitation.
authors.affiliation: Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China. luyanu@126.com
authors.forename: Yan
authors.initials: Y
authors.lastname: Lu
authors.forename: Xin-rong
authors.initials: XR
authors.lastname: Li
authors.forename: Ming-zhu
authors.initials: MZ
authors.lastname: He
authors.forename: Yan-gui
authors.initials: YG
authors.lastname: Su
authors.forename: Fan-jiang
authors.initials: FJ
authors.lastname: Zeng
mesh_terms: D002734:Chlorophyll / Q000378:metabolism*; D003300:Copper / Q000633:toxicity*; D005453:Fluorescence; D009532:Nickel / Q000633:toxicity*; D032443:Peganum / Q000254:growth & development / Q000502:physiology*; D010788:Photosynthesis / Q000187:drug effects* / Q000502:physiology; D036226:Seedlings / Q000187:drug effects / Q000502:physiology; D012989:Soil Pollutants / Q000633:toxicity
chemical_list: D012989:Soil Pollutants; D002734:Chlorophyll; D003300:Copper; D009532:Nickel