<em>In vitro</em> flowering - literature review

Abstract

In vitro flowering can be induced at different stages during development of in vitro plants by changes in chemical and physical factors related to the tissue culture process. Among the physical factors, photoperiod and temperature have been studied more detailed. Their inductive effect may vary in different species. Some physical factors can also be replaced by chemical stimuli. The chemical factors more frequently described in the literature are some growth regulators and the sucrose/nitrogen ratio. Cytokinins may induce flower development from various organs, but high concentrations can inhibit flowering and cause sprouting of vegetative buds. Gibberellins and polyamines (mostly spermidine) have a positive effect on flower induction. While, ethylene and auxin seem to be powerful inhibitors of in vitro flowering. However, auxins seem to be necessary during the early stages of floral development. An increase in the concentration of sucrose in the culture medium favor development of flowers in vitro, whereas a high concentration of nitrogen can stimulate vegetative growth of explants. Nevertheless, if the nitrogen concentration is too low, explants do not develop well. The aim of this literature review is to discuss most common factors related to in vitro flowering and to list the most relevant scientific literature about the subject from 1980 on. Key words: flower induction, growth regulators, inducers, tissue culture Abreviaturas: 2,4-D Ácido 2,4-diclorofenoxiacético, 2iP 2–isopentiladenina, ABA Ácido abscísico, AC Agua de coco, AG3 Ácido giberélico, AIA Ácido indol acético, AIB Ácido indol butírico, ANA Ácido naftalen acético, BAP Benciladenina, CAct Carbón activado, CasHid Caseína hidrolizada, DSDPs Plantas de día corto desplazado, GAx Giberelina x, LDPs Plantas de día largo, MES Ácido 2 (N-morfolino) etanosulfónico, MS Murashige y Skoog (1962), MT Murashige y Tucker (1969), PSF Plantas sensibles al fotoperíodo, Put Putrescina, PVP Polivinilpirrolindona, SAM S-adenosil-L-metionina, SAMDC S-adenosil-L-metionina descarboxilasa, SDPs Plantas de día corto, Spd Espermidina, Spm Espermina, TDZ Tidiazuron