Tissue culture and the propagation and genetic improvement of conifers: problems and possibilities.

The utilization of tissue culture in the propagation and genetic improvement of conifers holds promise of many benefits including faster multiplication of selected genotypes, faster development of improved genotypes and the transfer of genes between non-fertile parents. However, many of the techniques required for the realization of this potential remain to be developed. Furthermore, genetic differentiation of cells in culture creates uncertainty as to the fidelity of reproduction by micropropagation. Aspects of the problem of nuclear DNA variation during reproduction by tissue culture are reviewed with particular reference to the genus Pinus.