Paclobutrazol (PBZ), [2RS, 3RS]-1-[4-chlorophenyl]-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl) pentan-3-ol, consists of a triazole ring and a benzene ring-chloro linked to a carbon chain open. It is a plant growth regulator widely used in many crops in order to produce fruit throughout the year by inhibiting gibberellin synthesis; a hormone responsible for the vegetative plant growth. The biennial bearing is very serious problem in fruit crop production. Therefore, application of paclobutrazol is most widely studied in view of its high potential for controlling plant growth and development of fruit crops in general. It inhibits gibberellin biosynthesis at kaurene stage and has proved to be reduction of vegetative growth, promising for flower initiation in shoot bud, giving early and profuse flowering, increases fruit yield and improving quality regularly in alternate bearing cultivars. The growth regulating properties of paclobutrazol are mediated by changes in the levels of important plant hormones including the Gibberellins (GAs), Abscisic Acid (ABA) and Cytokinins (CK). Paclobutrazol (PBZ) affects the isoprenoid pathway, and alters the levels of plant hormones by inhibiting gibberellin synthesis and increasing cytokinins level. When gibberellins synthesis is inhibited, more precursors in the terpenoid pathway accumulate and that resulted to the production of abscisic acid. PBZ has been used to provide plant protection against numerous abiotic stresses such as chilling, water deficit stress, flooding and salinity. The main aim of this review is to focus upon contemporary information about paclobutrazol in fruit production. Its agronomic management includes it as an emerging technology to reduce vigour, promote flower induction and flower development in fruit trees with increased economic returns. Its use is banned in some countries because of concerns about residues that can cause harmful effects on the environment. Therefore, the aim of this article was to collect, analyse and summarise relevant information on the use of PBZ in fruit tree production and its possible risks to the environment. Usually it is applied as a soil application in the month of September-November in case of mango.
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