title: Effect of lanthanide chloride on photosynthesis and dry matter accumulation in tobacco seedlings.
abstract: To investigate the physiological effects of rare earth ions, we have studied the effect of LaCl3 on the photosynthetic light reactions in tobacco (Nicotiana tobacum). When treated with 5-20 mg/L LaCl3 in Hoagland solution by water culture, the dry matter accumulation of different parts in tobacco, the content of chlorophyll increased gradually, but decreased when the concentration of LaCl3 was > or = 50 mg/L. The optimum concentration for growth appeared to be about 20 mg/L of LaCl3 in nutrient solution. La3+ promoted the activities of the Hill reaction, Mg2(+)-ATPase, and stimulated the rate of photophosphorylation in chloroplast at low concentrations, but inhibited them at high concentrations. It is concluded that La3+ stimulated the growth of tobacco seedlings and accelerated the photosynthetic light reactions at suitable concentration in vivo.
authors.affiliation: Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.
authors.forename: W J
authors.initials: WJ
authors.lastname: Chen
authors.forename: Y
authors.initials: Y
authors.lastname: Tao
authors.forename: Y H
authors.initials: YH
authors.lastname: Gu
authors.forename: G W
authors.initials: GW
authors.lastname: Zhao
mesh_terms: D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism; D002412:Cations; D002734:Chlorophyll / Q000378:metabolism; D002736:Chloroplasts / Q000201:enzymology; D004305:Dose-Response Relationship, Drug; D007811:Lanthanum / Q000494:pharmacology*; D008027:Light; D010766:Phosphorylation / Q000187:drug effects; D010788:Photosynthesis / Q000187:drug effects*; D018521:Plant Physiological Phenomena; D010947:Plants, Toxic; D013997:Time Factors; D014026:Nicotiana / Q000187:drug effects* / Q000528:radiation effects*
chemical_list: D002412:Cations; C028521:lanthanum chloride; D002734:Chlorophyll; D007811:Lanthanum; D017301:Ca(2+) Mg(2+)-ATPase