MODULATION OF SOMATIC EMBRYOGENESIS IN HYPOCOTYL-DERIVED CULTURES OF GERANIUM (PELARGONIUM X HORTORUM BAILEY) CV RINGO-ROSE BY A BACTERIUM

The Ringo Rose cultivar of zonal geranium (Pelargonium x hortorum Bail ey) has been shown to be morphogenetically unresponsive. Attempts to i mprove somatic embryogenesis using various seed stress treatments befo re germination proved ineffective. However, bacterial contamination of one of the seed-stress treatments led to infected explants that had a significant increase in frequency of high-quality somatic embryos. Th e co-cultivation of explants with the isolated bacterium (tentatively identified as Bacillus sp.) was found to be repeatable, and potentiall y represents a novel way to improve morphogenesis in geranium and poss ibly other species.