SOMATIC EMBRYOGENESIS IN WHITE SPRUCE (PICEA-GLAUCA) - GENETIC-CONTROL IN SOMATIC EMBRYOS EXPOSED TO STORAGE, MATURATION TREATMENTS, GERMINATION, AND CRYOPRESERVATION

Genetic controls for growth of embryogenic cultures, storage, maturation treatments, germination and cryopreservation in white spruce somatic embryogenesis (SE) were examined. These SE processes were under genetic control but less strongly so than the initiation phase. For all the SE characters examined, variance due to clones within families was significant and often the largest genetic component of variance. This was further partitioned using an additive-dominance-epistasis model. A relatively-large proportion of the total genetic variance was due to epistatic variance in the maturation and germination of somatic embryos. Embryogenic lines were cryopreserved easily without a distinct genetic influence being noticed.