Abstract
A new tissue culture medium was developed by mixing colloidal buffer agents together with tissue culture medium solution. Powders of zeolite, bentonite and charcoal were added to the medium solution as colloidal buffer agents. By adding colloidal buffer agents, the buffering capacity of pH in the medium increased significantly against both acidification and alkalization. When embryos taken out from Phaseolus vulgaris seeds were grown in media containing colloidal buffer agents, the length of plantlets formed from the embryos became larger and the dry weight of the plantlets became heavier than plantlets grown in media containing no buffering agents. This suggests that colloidal buffer agents stabilize the pH of the culture medium and sustain cell elongation and growth of plantlets for growing period during tissue culture. Furthermore, the addition of colloidal buffers in culture media had an additional benefit of preventing the degradation of organic substances in the culture media while the media were heated for the purpose of sterilization.
