New Aspects of Plant Growth Regulators

This chapter gives an overview of PGRs, their current use and new developments. It is a summary of available knowledge and a tool for deeper and more intense analyses of specific items. The literature given at the end includes reviews and specialist summaries. Internet links provide detailed and up-to-date overviews, such as chemical structures, including the chemical names [1], chemistry, use and environmental aspects [2-4], and summarized overviews [5, 6]. 

Classically, there are five main categories of naturally occurring PGR, the auxins (lAA, NAA, IBA, 2,4-dichlorophenoxyacetic add), gibbereHins (GA), cytoM-nins (kinetin, benzyladenin, zeatin), ethylene, and growth inhibitors like abscisic acid (ABA). 

Ethylene effects were firstly described by Nejebulov 1901 [9], but ethylene as a hormone could be identified only after gas chromatography was established in 

Modem Crop Protection Compounds. Edited by W. Kramer and U. Sdiirmer Copyright 2007 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 978-3-527-31496-6 

Indote-bLrtyw cid (IBA) Ban yladaniii Mepiquat Ctilorida Probaxadiona calajprrt  

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In the past year, reviews on 1,8-naphthyridines, perimidines, polyazaphen-anthrenes, 3-azabicyclo[3.3.1]nonanes, and 1,2- and 2,1-benzothiazines have appeared. Reviews on specialist aspects of pyridine chemistry are devoted to the reactions of newly available pyridines, a,a -disubstituted pyridines, the reactions of pyridines with nucleophiles, the electrochemistry of IjT-disubstituted 4,4 -bipyridinium ions (the viologens such as paraquat), dihydropyridines, and 4-aryl-dihydropyridines (a new class of calcium antagonists). Reviews have been published on the cyclization of oximes and amides to quinolines and isoquinolines, quinoline- and isoquinoline-diones, benzo[fl ]- and benzo[c]-quinolizinium ions, azachrysene preparation, quinazolines with plant-growth-regulating and biocidal activities, quinazolines in pharmaceutical research, isotopic hydrogen exchange in... 

Bryant JA (1976) The cell cycle. In Bryant JA (ed) Molecular aspects of gene expression in plants. Academic Press, London New York, pp 177-216 Buggeln RG (1976) Auxin, an endogenous regulator of growth in algae J Phycol 12 355-358... 

R. Bearder, Plant hormones and other growth substances - their background, structures and occurrence, "Encycopedla of Plant Physiology, New Series, Vol. 9, Hormonal Regulation of Development I Molecular Aspects," J. MacMillan, ed., Sprlnger-Verlag, Berlin (1980). 

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