title: Label Distribution in Tissues of Wheat Seedlings Cultivated with Tritium-Labeled Leonardite Humic Acid.
abstract: Humic substances (HS) play important roles in the biotic-abiotic interactions of the root plant and soil contributing to plant adaptation to external environments. However, their mode of action on plants remains largely unknown. In this study the HS distribution in tissues of wheat seedlings was examined using tritium-labeled humic acid (HA) derived from leonardite (a variety of lignites) and microautoradiography (MAR). Preferential accumulation of labeled products from tritiated HA was found in the roots as compared to the shoots, and endodermis was shown to be the major control point for radial transport of label into vascular system of plant. Tritium was also found in the stele and xylem tissues indicating that labeled products from tritiated HA could be transported to shoot tissues via the transpiration stream. Treatment with HA lead to an increase in the content of polar lipids of photosynthetic membranes. The observed accumulation of labeled HA products in root endodermis and positive impact on lipid synthesis are consistent with prior reported observations on physiological effects of HS on plants such as enhanced growth and development of lateral roots and improvement/repairs of the photosynthetic status of plants under stress conditions.
authors.affiliation: Lomonosov Moscow State University, Department of Soil Science, Leninskie Gory 1-12, 119991, Moscow, Russia.|Bach Institute of Biochemistry, Research Center of Biotechnology of RAS, 33, bld. 2 Leninsky Ave., Moscow 119071, Russia.
authors.forename: Natalia A
authors.initials: NA
authors.lastname: Kulikova
authors.affiliation: Lomonosov Moscow State University, Department of Soil Science, Leninskie Gory 1-12, 119991, Moscow, Russia.
authors.forename: Dmitry P
authors.initials: DP
authors.lastname: Abroskin
authors.affiliation: Lomonosov Moscow State University, Department of Chemistry, Leninskie Gory 1-3, 119991, Moscow, Russia.
authors.forename: Gennady A
authors.initials: GA
authors.lastname: Badun
authors.affiliation: Lomonosov Moscow State University, Department of Chemistry, Leninskie Gory 1-3, 119991, Moscow, Russia.
authors.forename: Maria G
authors.initials: MG
authors.lastname: Chernysheva
authors.affiliation: Lomonosov Moscow State University, Department of Chemistry, Leninskie Gory 1-3, 119991, Moscow, Russia.
authors.forename: Viktor I
authors.initials: VI
authors.lastname: Korobkov
authors.affiliation: Lomonosov Moscow State University, Department of Biology, Leninskie Gory 1-12, 119991, Moscow, Russia.
authors.forename: Anton S
authors.initials: AS
authors.lastname: Beer
authors.affiliation: Zelinskii Institute of Organic Chemistry of RAS, 119991, Moscow, Russia.
authors.forename: Eugenia A
authors.initials: EA
authors.lastname: Tsvetkova
authors.affiliation: Komarov Botanical Institute of RAS, 2 Professor Popov str., St. Petersburg, 197376, Russia.
authors.forename: Svetlana V
authors.initials: SV
authors.lastname: Senik
authors.affiliation: Bach Institute of Biochemistry, Research Center of Biotechnology of RAS, 33, bld. 2 Leninsky Ave., Moscow 119071, Russia.
authors.forename: Olga I
authors.initials: OI
authors.lastname: Klein
authors.affiliation: Lomonosov Moscow State University, Department of Chemistry, Leninskie Gory 1-3, 119991, Moscow, Russia.
authors.forename: Irina V
authors.initials: IV
authors.lastname: Perminova
mesh_terms: D000222:Adaptation, Physiological; D006812:Humic Substances / Q000032:analysis*; D007553:Isotope Labeling; D008903:Minerals / Q000378:metabolism*; D010788:Photosynthesis; D018517:Plant Roots / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism; D058526:Plant Vascular Bundle; D036226:Seedlings / Q000378:metabolism*; D013312:Stress, Physiological; D014908:Triticum / Q000378:metabolism*; D014316:Tritium / Q000378:metabolism
chemical_list: D006812:Humic Substances; D008903:Minerals; C568542:leonardite; D014316:Tritium