Abstract
A forced ventilation micropropagation system was developed, and with this system, single-node leafy stem cuttings of sweetpotato (Ipomoea batatas (L.) Lam., cv. Beniazuma) were cultured on cellulose plugs or vermiculite used as supporting materials with Murashige and Skoog (1962) nutrients but without sugar, i.e., photoautotrophically. The inlet CO2 concentration of the system was 1 500μmol mol-1 and the photosynthetic photon flux on the culture shelf was 150μmol m-2 s-1. The net photosynthetic rate and dry mass of sweetpotato plug plantlets from the forced ventilation treatment on day 22 were 30-40 times and 4-6 times greater, respectively, than those of the plantlets grown under the conventional, photomixotrophic micropropagation system with natural ventilation and gelled agar medium containing sugar.
