title: The endogenous hormones in soybean seedlings under the joint actions of rare earth element La(III) and ultraviolet-B stress.
abstract: The dynamic state of endogenous hormone content in soybean seedlings was investigated for a further demonstration of alleviating the damage of the ultraviolet ultraviolet-B (UV-B) radiation in the La(III)-treated soybean seedlings under UV-B stress. Using hydroponics culture, the effects of lanthanum(III) on the contents of endogenous hormone under elevated ultraviolet-B radiation (280–320 nm) was studied. The results showed that the content of indole-3-acetic acid (IAA) in soybean seedlings decreased initially and then increased when the seedlings underwent UV-B treatment during the stress and convalescent period; this was compared with a control; acetic acid oxidase (IAAO) activity increased at first (first to fifth day) and then decreased (sixth to 11th day). A similar change of abscisic acid content and IAAO content in soybean seedlings occurred; gibberellic acid (GA) content decreased during the experiment compared with control. The content of IAA and GA in soybean seedlings with La(III) + UV-B treatment was higher than those of UV-B treatment; IAAO activity and GA content in soybean seedlings with La (III) + UV-B treatment were lower than those of UV-B treatment. It suggested that the regulative effect of La(III) at the optimum concentration on endogenous hormone improved the ability of plant stress resistance, and its protective effect against low UV-B radiation was superior to high UV-B radiation. The defensive effect of La(III) on soybean seedlings under UV-B stress was carried out on the layer of defense system.
authors.affiliation: School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, People's Republic of China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Peng
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhou
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D005875:Gibberellins / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism; D007811:Lanthanum / Q000494:pharmacology*; D036226:Seedlings / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects*; D013025:Glycine max / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects*; D014466:Ultraviolet Rays
chemical_list: D005875:Gibberellins; D007210:Indoleacetic Acids; D007811:Lanthanum; C030737:indoleacetic acid; D000040:Abscisic Acid; C007842:gibberellic acid