Discussion
Under suitable storage conditions, Ps. fluorescens has been
shown to survive in alginate beads for up to 14 years
(Bashan and Gonzalez 1999) and for effective colonization
of plants, inocula within alginate beads should be above
105 CFU bead)1 (Bashan 1986). The genetically modified
micro-organisms Ps. fluorescens F113Rifpcb survived
above this threshold in alginate beads for more than
250 days under ambient storage conditions. A related
strain, F113LacZY, also displayed similar survival patterns
in alginate but over a much shorter time period (Russo
et al. 1996).