Novel bioreactor technology for mass propagation of potato microtubers

Potato (Solanum tuberosum L. ssp. tuberosum) microtubers were produced in vitro with Liquid Lab™ Rocker system. A thin-layer liquid culture was applied together with a regular pitch in autoclavable simple plastic vessels. All cultures were carried out at room temperature without contamination problems. Each cultivar tested (Asterix, Timo, Van Gogh, Velox) formed microtubers in the Liquid Lab system. The mean number of microtubers per vessel (50 explants) varied between 30 (cv. Asterix in 8 weeks tuber induction) and 75 microtubers (cv. Velox in 11 weeks tuber induction). Majority (63%) of the microtubers was sufficient by size and weight (above 200 mg) for further storage at dormancy (4°C). The cv. Velox yielded the highest number of microtubers with cultivation capacity. As a result of prolonged microtuber induction of 2–3 weeks, more microtubers with competence for cultivation were obtained per cultivar, except for cv. Van Gogh. Still, the mean weight of Van Gogh microtubers was significantly higher after prolonged microtuber induction (0.67 g) than after short induction (0.51 g). In conclusion, Liquid Lab™ Rocker system is a novel, efficient and rapid system for mass propagation of potato.