Behaviour of plant material issued from in vitro tuberization

In vitro bacterization of potato microplants with a pseudomonad bacterium, Pseudomonas spp. strain PsJN, induces developmental modifications which mak e them more hardy and more vigorous upon transplanting. The paper reviews p revious experiments and presents recent data on the post-inoculation microp lant generation response of genetically engineered and non-engineered clone s, microplant response to CO2 supplement, as well as the results of field e xperiments conducted between 1987 and 1993. Production of minitubers under greenhouse conditions and tuberization under heat stress in growth chamber are also presented. The use of the in vitro culture system for the developm ent of microbial associations benefitting crop rotations is postulated.