Abstract:
The potential of cassava starch as an alternative and cheap gelling agent for potato in vitro culture
micro-propagation media was investigated. A two-factor experiment in randomized complete block
design was conducted. Four levels of gelling agents; 10% (w/v) cassava starch, 8% cassava starch
mixed with 0.25% agar, 0.8% agar and a liquid medium, were evaluated using three selected Kenyan
potato cultivars (Tigoni, Asante and Kenya Sifa). Cassava starch at 10% gave adequate support of
explants, though it had low viscosity and softened at 42 days after explant inoculation. Cassava starch
mixed with 0.25% agar provided the same firmness as 0.8% agar and maintained gel integrity
throughout the culturing period of 84 days. Survival in- and ex vitro was lowest in liquid medium
culture. Potato transplants from the liquid medium and cassava starch gelled medium had similar (p >
0.05) mean number of nodes and biomass. These mean values were significantly higher compared to
the transplants from the agar gelled medium. The use of 10% cassava starch reduced cost by 42.5% in
comparison with use of agar.
