Culture medium and growth regulators on <i>in vitro</i> multiplication of <i>Psidium guajava</i> L.

Abstract

Guava (Psidium guajava L.) cultivar `Dwarf Cuban Red 18-40 EEA' has high yields. For large-scale propagation, micropropagation is a possible solution. The aim of this study was to determine the effect of two culture media, two cytokinins and an analog brasinoesteoides (DI-31) in the in vitro multiplication of this cultivar. Two culture media (MS and WPM), three concentrations of benzylaminopurine (BAP) (0.5, 1.0, 1.5 mg l-1), three of kinetin (0.5, 1.0, 1.5 mg l-1) and two DI-31 (0.01 and 0.02 mg l-1) were evaluated. The variables evaluated were: number of shoots, number of leaves, shoot length and multiplication coefficient. It was found that the type of culture medium influenced the shoot multiplication of guava. The number of shoots, shoot length and multiplication coefficient were determined by the type and concentration of cytokinin added to the culture medium. With the use of WPM culture medium with 1 mg l-1 BAP It was obtained the highest values of the variables evaluated. The use of DI-31 promoted the shoot growth without affecting the multiplication coefficient. Key words: benzylaminopurine, DI-31, kinetin, guava, micropropagation, multiplication phase