Influence of Media Composition and Genotype on Potato (Solanum tuberosum L.) Microtuberization
Potato (Solanum tuberosum L.) is one of the most important crops in the world. Providing virus free, early generation seeds is a major potato production problem. Production of early generation potato minitubers under greenhouse conditions still have the risk of insect contamination and virus transmission. In vitro microtuberization provides an alternative method in the production of clean seed. The purpose of this study was to determine the optimum media for microtuber production in four potato genotypes, i.e. AOTX98202-1RU, ATX9202-3RU, ATTX98468-5R/Y and ATTX98518-5P/Y. The four genotypes were cultured in Murashige and Skoog (MS) media with addition of 6% sucrose, with or without 2 g L-1 phytagel, and with or without 10 mg L-1 kinetin. Two nodal cuttings were cultured in each vessel with five replications. Culture were incubated with 16 h/day light and 23 °C for two weeks, and then moved to a cooler growth room at 16 °C for two weeks, followed by incubation in the dark at 16 °C for 6 weeks, and observed for 10 weeks. Result shows that genotypes responded differently to the media. 2 g L-1 phytagel + 10 mg L-1 kinetin treatment (T4) was an effective treatment to enhance microtuber growth in genotype ATTX98468-5R/Y and ATTX98518-5P/Y. ATTX98468-5R/Y in T4 media produced the highest number of microtubers (4.2 microtubers/vessel), while ATTX98518-5P/Y produced the heaviest average fresh weight (363.6 mg). Results suggest the importance of developing specific protocols for each genotype for optimum production of microtubers.
Keywords: genotype, in vitro, kinetin, microtuber, phytagel