Our experiments showed that although the average number of GGBs initially induced per leaf explant was less than 10 and an increase in the PGR concentrations could not improve this number (Table 2). However GGB initiation is not the final object of these tissue culture operations, so the low GGB yield does not become a hindrance in the whole procedure aimed at the mass propagation of P. bifurcatum. After the initiation and separation of GGBs, they could be rapidly turned into a multiplication phase given the specific PGR combination. These GGB cultures will soon become a key and continuously supplied materials for propagation purposes.