EFFECT OF H2O2 ON THE in vitro TUBERIZATION OF Solanum tuberosum L.

Abstract

The production of potato crops (Solanum tuberosum L.) is limited by the lack of healthy, certified, and good quality seed. In vitro tuberization could satisfy this need. Growth regulators and molecules such as H2O2 have been used to induce microtubers. The objective of this investigation was to evaluate the effect of H2O2 as inducer of microtuberization in three subcultures. The hypothesis suggests H2O2 has an inducing effect on the in vitro tuberization of S. tuberosum in more than one subculture. The experimental design was a 2?6?3 factorial design, in which the main factors were: H2O2 treatment, observation days, and subcultures; each subculture had 12 experimental units with three replicates per treatment. Nodal explants of potato microplants were immersed in 5 mM of H2O2 for 1 h, and then they were incubated in a MS medium, during 30 d: this was the first subculture. One part of the microplants of this subculture were transferred to a tuberization medium, and another part was subcultured twice. The first subculture was submerged in H2O2. The inducing effect of H2O2 was observed in the microtuberization of the three subcultures. H2O2 stimulated the in vitro tuberization in the three subcultures during the observation days. The largest number of microtubers (MT) was recorded in subculture II; however, the inducing effect of H2O2 was observed in all three subcultures. The correlation between the weight and size of MT was positive (r2 ?0.63) and 64% of MT sprouted before the harvest. H2O2 could be included in MT intensive production systems.