the accumulation of PR1 mRNA levels
caused by B. subtilis IAB/BS03 is independent of SA
accumulation, which is in agreement with previous research
(Pieterse et al. 1996). Thus our results support the
contention that specific signal transduction pathways
activated by Bacillus spp. during ISR depends on the
strain, the host plant and the pathogen (Kloepper et al.
2004). It would be interesting to test PR1 activation by
B. subtilis IAB/BS03 in tomato plants that have impaired
SA or JA signalling.