Efficacy of the combination tebuconazole-Bacillusin the control of theFusarium culmorumresponsible forFusariumcrown rot in durum wheat

The results of this study showed that the tested antagonistic bacteria namely Bacillus amyloliquefaciens BB19 (B19) and Bacillus atrophaeus B16 (B16) and fungicides (tebuconazole, fludioxonil-difénoconazole and difénoconazole) inhibit significantly the “in vitro” growth of the two Fusarium culmorum isolates (FC1 and FC2). Contrarily, in the growth chamber experiments, the B19 and B16 strains and tebuconazole each alone showed a lower inhibition effect. However, the results of the combination method were promising. The losses caused by the FC1 and FC2 isolates were significantly reduced and the growth parameters were significantly improved. In the presence of FC2 isolate, the combination “tebuconazole-B19” gave more than 50% increase in the length of the root system and 76.42% enhancement in the fresh weight of the root system compared to the positive control. It was also observed that necrosis and browning symptoms on wheat seedlings disappeared. Statistical analysis revealed that the combination “tebuconazole-B19” was synergistic regarding all the studied growth parameters.