Interactive effect of genotype and medium on microtuberization of potatoes (Solanum tuberosum L.) grown in vitro

This work investigates the interactive effect of six culture media and three photoperiods (darkness, 16h/8h, 8h/16h) on the microtuberization of four potato varieties (Spunta, Désirée, Kondor and Bartina). The objective is to determine the best tuberization under these growing conditions. The measured parameters which are related to the suitability of the tuberization characteristics are: the morphological aspects (shape, position) and the biometric ones (number and diameter of tubers). The obtained results permit to valorize the meristems that constitute the starting explant, and their good organogenetic skills to provide the first generation of micropropagation with healthy vitroplants in a sufficient quantity. Thus, the grown vitroplants on the medium (MS/2+BAP+COU) presented the best values which are related to the percentage of tuberization, the number of microtubercles / vitroplants and weight of tubers. Moreover, the Bartina genotype showed a remarkable superiority over its media and under a 16h/8h photoperiod except for the diameter of the tubers, where this genotype had the best diameter over the medium (MS/2+KIN) under an 8h photoperiod.