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, maturati on treatments, germination and cryopreservation in white spruce somati c embryogenesis (SE) were examined. These SE processes were under gene tic control but less strongly so than the initiation phase. For all th e SE characters examined, variance due to clones within families was s ignificant and often the largest genetic component of variance. This w as further partitioned using an additive-dominance-epistasis model. A relatively-large proportion of the total genetic variance was due to e pistatic variance in the maturation and germination of somatic embryos . Embryogenic lines were cryopreserved easily without a distinct genet ic influence being noticed.