The Effects of Sucrose and Hormone on In vitro Microtuberization of Three Potato Cultivars

The aim of this study was to evaluate the effects of cultivar, sucrose and hormone on in vitro microtuberization of potato (Solanum tuberosum L.). For this purpose, the experiment was done as a factorial based on completely randomized design with three replications on three potato cultivars so called Agria, Marfona and Satina. In this research, four levels of sucrose (40, 60, 80 and 100 g.l-1) were studied in combination with with two hormonal treatments (hormone free and medium containing 10 mg.l-1BAP and 0.5 mg.l-1NAA) on explants of these cultivars. The number, weight, diameter and eye of microtubers induced per plantlet were measured at 12 weeks after culture initiation. Analysis of variance showed significant differences between cultivars, sucrose and hormone levels for all traits. In this experiment, the highest values for all traits studied among cultivars belong to Satina, while Marfona had the lowest values for all of traits except number of microtubers that was better than Agria. Among the four concentrations of sucrose, the highest values for all traits studies was observed in the medium containing 80 g.l-1 sucrose, followed by mediums containing 60, 40 and 100 g.l-1 sucrose respectively. Although tuberization was initiated in the absence of hormone because of sucrose, nevertheless, the presence of hormone accelerated microtuberization. In general, results showed that the highest number, weight and diameter of microtuber and eye number were obtained in the Stina cultivar, 80 g.l-1 sucrose and hormonal combination10 mg.l-1BAP and 0.5 mg.l-1 NAA.