Progress in Somatic Embryogenesis of Japanese Pines.

Somatic embryogenesis (SE) in not only one of the most promising techniques for mass propagation of selected trees, but also is a valuable tool for basic research studies in cell biology and genetic engineering, and it allows the long-term conservation of genetic resources by cryopreservation techniques. This review reports the most recent progress in SE, protoplast culture, and cryopreservation of four important Japanese pines ( var. , and ). Induction of embryogenic tissues (ET), embryogenic culture maintenance/proliferation, production of somatic embryos, germination, and conversion to plants are described focusing on the protocols most commonly reported for plant production in species through to SE.