Reculture of Frozen Tissue Culture Material - Materials subjected to cryopreservation may show some special requirements during reculture. For example, shoot tips from freeze preserved seedings of tomato required GA₃ for developing into shoots (they formed callus in the absence of GA₃), while normal shoot tips of tomato do not require GA₃.

Similarly survival of carrot plantlets was greatly improved by activated charcoal. Thus, it is necessary to determine the optimum conditions for reculture of different plant species, particularly when commonly used regimes fail.