The capacity to form flower buds in thin-layer explants was studied in flowering plants of several species, cultivars, and lines of Nicotiana differing in their response to photoperiod. This capacity was found in all biotypes examined and could extend into sepals and corolla. It varied greatly, depending on genotype, source tissue and its developmental stage, and composition of the culture medi...

ENETIC tumors in Nicotiana species hybrids have been reported by several Ginvestigators. These tumors are formed in certain specific hybrid combinations on stems, roots, and occasionally on leaves of all or part of the F, progeny. Since the discovery by KOSTOFF (1930) of nine interspecific tumorous hybrids, almost 20 additional hybrid combinations have been reported in which the entire progeny ...