Totipotency, somatic embryogenesis, and Harry Waris (1893-1973)

F, C, Steward and Jakob Reinert in the lute 1950s, independently and with d ifferent degrees of scientific exactness, demonstrated that somatic cells o f cultivated carrot can produce embryo-like structures in aseptic culture, growth substances in the nutrient medium were viewed as central to the proc ess. The now classic papers of Steward and Reinert have found a special and enduring place in the literature of plant development, But Harry Waris als o deserves credit for his observation that vegetative cells sloughed off fr om aseptically germinated seedlings reared in liquid nutrient medium can pr oduce "embryos". In his studies, seedlings of Oenanthe aquatica (Umbellifer ae) were maintained in culture for protracted periods under nutrient condit ions designed to foster imbalance in protein metabolism, but without exogen ous growth hormones, Seedlings placed in media with high concentrations of glycine grew normally for 3-4 months; after this a,"period of morbidity" oc cur;cd, followed bg production of new plants from the root tips. These new plants, later called "neomorphs". in turn reproduced by colorless outgrowth s of leaf epidermis, Such outgrowths, and "nodules" formed in a callus prod uced by the original seedlings, passed through stages described as "nodule" , "fusiform", and a stage will two or more ''lobes". Transfer of the neomor phs to a medium lacking glycine resulted in the development of normal plant s, We show that Waris was among the first, if not the first, to observe and recognize somatic embryo production in aseptic culture, and indeed to cap them "embryos''. We also discuss his investigations in the context of under standing development at the cellular level, then and non.