Effect of explant type and concentration of 2,4-dichlorophenoxyacetic acid on callus formation in Morus albaL.

Abstract

The objective of the work was to evaluate the effect of explant type and concentration of 2,4-
dichlorophenoxyacetic acid on callus formation, in Morus alba L. As explant sources leaf blades, stems and
petioles were used , obtained from cuttings which produced growths under laboratory conditions. The basal
culture medium was constituted by MS salts and vitamins (1962), with different concentrations of 2,4-D (0; 0,5;
1,0 and 2,0 mg.L-1). A completely randomized experimental design was used. Callus formation in all explant
types started in the first 15 days after the in vitro establishment. Callogenesis only occurred in the culture
media with 2,4-D. The callus formation zone, callus color and texture depended on the explant type used. The
increase of 2,4-D concentration in the culture medium increased callus size, with the best results in the
concentrations 1,0 and 2,0 mg.L-1.