EFFECTS OF ACTIVATED-CHARCOAL EFFECTS ON INDUCTION AND DEVELOPMENT OFMICROTUBERS IN POTATO (SOLANUM-TUBEROSUM L)

The aim of this research was to compare hormone-free medium with media with regulator substances (activated charcoal, cytokinins, polyamine biosynthesis inhibitor and chlorocholine chloride) used for microtuber induction and development. Explants of cvs Monalisa, Primura and Spun ta were multiplied by subculturing nodal segments on plant growth regu lator-free Murashige & Skoog (1962) (MS) medium. When the plantlets ha d 6-8 nodes, single-node stem segments were excised and transferred to eight tuberisation media, each consisting of MS basal components supp lemented with sucrose (8% w/v) and various regulator substances. The c ontrol was a regulator-free medium including only sucrose. Results wer e expressed as the number and weight of microtubers per nodal explant. The cultivars showed wide variations in the mean weight of microtuber s, ranging from 44.6 mg (Primura) to 77.5 mg (Spunta), and nearly all plants produced tubers. Medium containing activated charcoal gave the highest rate of tuberisation and the largest microtubers. It thus play ed a role in optimising conditions for rapid, mass tuberisation of the se cultivars, and produced large microtubers for field planting.