Meeting Report: Botanical Congress, Hamburg, 2007

Abstract

An overview on plant science in Germany was presented when the German Botanical Society held its biannual meeting ‘‘Botanikertagung 2007’’ in Hamburg, 3-7 September 2007. This meeting marked the 125th anniversary of the society. Although this conference traditionally attracts plant scientists from Germany, many renowned international speakers gave plenary or invited lectures. Several sessions addressed plant hormones and related metabolic or developmental processes. The sessions ‘‘Phytohormones—Metabolism and Function I and II,’’ ‘‘Sensing: Receptors and Signalling I and II,’’ and ‘‘Developmental Biology I and II,’’ each covered different fields but all gave interesting updates and summaries of recent research. The sessions consisted of up to ten scientific talks with discussions and were accompanied by poster presentations. The ‘‘Phytohormones—Metabolism and Function’’ session was opened by the invited speaker E. Prinsen (University of Antwerp), who discussed bacterial auxin and cytokinin biosynthesis and presented insights on the controlled auxin and cytokinin production by bacterial strains ranging from pathogens over plant growth-promoting rhizobacteria to obligate symbionts. The next two contributions addressed the topics ‘‘IAA Modified Proteins and Their Potential Role in Auxin Homeostasis’’ (C. Seidl, University of Dresden) and ‘‘Inositol-Phospholipids as Multifunctional Effectors’’ (I. Heilmann, University of Gottingen). A comprehensive overview of ‘‘Gibberllins Regulating Pumpkin Development’’ was given in the invited talk of T. Lange (TU Braunschweig), who elucidated organ-specific GA biosynthesis in young shoot tissues of pumpkin emphasizing the role of the rate-limiting GA 20-oxidation and GA 3oxidation. The second part of the session was opened by T. Werner (FU Berlin), who highlighted ‘‘Cytokinin Catabolism Regulating Plant Development.’’ T. Werner summarized work in which cytokinin oxidases/dehydrogenase genes were used to create plants with constitutively or tissuespecific reduced cytokinin contents, thus revealing different roles of cytokinins in root and shoots. Furthermore, loss-of-function mutants uncovered the fact that individual AtCKX genes regulate meristematic activities of shoot and root meristems in a redundant manner. The subsequent talk by J. Ludwig-Muller (University of Dresden) addressed ‘‘GH3 Proteins from Physcomitrella Linking Auxin and Jasmonate Homeostasis.’’ The topic ‘‘Jasmonates as Inducers of Calcium Signals in the Nucleus of Plants’’ was presented by A. Mithofer (MPI Chemische Okologie, Jena). F. Bittner (TU Braunschweig) presented ‘‘Mitochondria and Iron as Novel Players in ABA Biosynthesis.’’ The Phytohormone session was closed by the invited lecture of M. Sauter (University of Kiel) on ‘‘Phytosulfokine-a Regulating Root Growth and Reproductive Processes in Arabidopsis.’’ Phytosulfokine-a (PSK-a) is a pentapeptide that ubiquitously occurs in higher plants and can act as a growth factor. Promotor:GUS studies of the precursor genes as well as of the receptor gene AtPSKR1 revealed expression in roots. The relevance of PSK-a as a root-growth-signaling compound was further demonstrated by AtPSKR1 receptor knockout plants as well as by application of synthetic PSK-a. Receptor knockout plants also revealed the role of PSK-a signaling in seed formation. K. von Schwartzenberg (&) H. Luthen University Hamburg, Biozentrum Klein Flottbek und Botanischer Garten, Ohnhorststr. 18, 22609 Hamburg, Germany e-mail: kvschwartzenberg@botanik.uni-hamburg.de