Culture media in the in vitro cultivation of Dioscorea spp.

Abstract

The composition and physical state of the culture medium, as well as the effect of supplementation in different subcultures, are determining factors for the regeneration and good development of the in vitro explant. Therefore, this study aimed to study the effect of the culture medium on micropropagation during four subcultures, depending on the growth variables of the genotypes Dioscorea alata L., D. alata var. purpurea (Roxb.) A. Pouchet, and D. rotundata. Nodal segments of 1 cm length of plants previously cultivated in vitro were introduced into 10 mL of MS culture media supplemented with 100 mg L-1 of inositol, 20 mg L-1 of cysteine, 0.20 mg L-1 of ANA, 0.08 mg L-1 of AG3 and 0.05 mg L-1 of BAP and 2GGC basic, both in solid and liquid states plus 3 g L-1 of activated charcoal and 30 g L-1 of sucrose and the pH adjusted by 5.8 before autoclaving. At every 30 days of in vitro culture, development variables, percentage of responsive explants, and the number of calluses were evaluated. The MS and solid 2GGC media are the most suitable for the multiplication of the genotypes D. alata and D. alata var. purpurea. For the D. rotundata genotype, the solid MS medium is the most suitable for its in vitro multiplication.