Investigations on the Inhibitory Effect of Agar and the Function of Active Carbon in Anther Culture

The influence of agar in the culture medium on the yield of embryos from anther cultures of Nicotiana tabacum has been systematically tested. A liquid medium in the complete absence of agar was significantly better than any solidified agar media. It was observed that higher numbers of embryos aborted prematurely in agar-cultured anthers and it could be shown that the agar used contained inhibitory substances. By equilibrium dialysis it was demonstrated that active carbon, which is already successfully used in anther culture, func­ tions by absorption of these inhibitory compounds. As a result of this finding it was possible to increase the embryo yield of the experiment using more purified commercial agar types and agarose. Further in Datura where a liquid medium is not favorable for embryogenesis it was possible to increase the yield through the use of highly purified solidifying agents in the culture medium.