Monosomic additions in beet (Beta vulgaris) carrying extra chromosomes of B. procumbens

Summary Alien monosomic additions in beet (Beta vulgaris), each carrying one of the nine chromosomes of B. procumbens, were grown in vivo and in vitro to study the effect of the alien chromosomes on plant development. All additional chromosomes caused a reduction of the growth rate in vivo, which, in one case was so strong that some of the plants died as seedlings. In general, the morphological plant characteristics were not very useful to distinguish the addition types; this could have been the results of the wide variation in the recipient parent. However, some developmental characteristics proved to be highly chromosome-specific; for plants in vivo this was annuality, in combination with early or late flowering. If grown in vitro, chromosome specificity was observed for growth type (rosette or elongated stem), occurrence and rate of vitrification, occurrence and morphology of wound callus, formation of additional meristems on the midribs of leaves, formation of roots and a specific reaction to benzylaminopurine (BAP) the medium. Two chromosome types of B. procumbens caused resistance to the beet cyst nematode.