Callus formation from potato tuber disks

Abstract

In vitro tissue culture systems that drive explants to undifferentiation produce the so-called callus. Under these conditions. diverse genetic changes can occur in the cells, thus leading to somaclonal variation. Such variation is highly attractive to breeding programs since it makes possible in vitro selection of superior characteristics, as compared to the original cultivars. 

The objective of this research was to determine the best culture media for callus generation in different potato genotypes. The starting materials were tuber disks from the cultivars Alpha, Norteña, Mondial and Clon AN-1; these were cultured in GerberR bottles with the media Engvild (1973), Murashige & Skoog (1962), Stantz & Steward (1959- B), and Lam (1975). The explants in culture media were located in an incubation room at 25°C and darkness during six weeks. Afterwards, the following quantitative variables were evaluated: callus fresh weight, callus dry weight, and difference between fresh and dry callus weight. The recorded qualitative variables were callus consistency and color. The results indicate that callus induction was successful with the four media and the four cultivars; among these the Clon AN-1 was outstanding. Medium Engvild (1973) -integrated by inorganic salts of M/S (1962), vitamins N & N, glycine, NAA, and kinetin— gave the best callus in all cultivars. Finally, the tuber disks of Clon AN-1 cultured in Engvild (1973) medium gave the callus with best fresh and dry weight, as well as with best consistency and color.