Strategies to propagate Vaccinium nuclear stocks for the Canadian berry industry

Vacinium fruits are genetically heterozygous species characterized as "not coming true from seed". Conventional methods for vegetative propagation of these species, although successful, are slow and labour-intensive, and few propagules can be produced from one plant of a selected clone or hybrid. Micropropagation techniques are important for clonal multiplication, germplasm improvement and gene conservation of Vaccinium fruits cultivated in Canada including blueberries, cranberries and lingonberries. In vitro propagation of these species using axillary bud proliferation and adventitious shoot regeneration has been investigated in a number of studies. Morphogenesis seems to be highly dependent on plant growth regulators and media used for culture, and this dependence is genotype specific. The paper presents the progress in-depth of various aspects of the in vitro culture of Canadian Vaccinium species for their commercial production. Also discussed are techniques for clone rejuvenation and plant tissue culture for mass propagation of Canadian Vaccinium nuclear stocks.