بيان ژنهاي كيتيناز (ech42 nagl ) در قارچ Trichoderma atroviride در برهمكنش با باكتري Pesudomonas fluorescens

THE EXPRESSION OF CHITINASE GENES (NAG1 AND ECH42) OF TRICHODERMA ATROVIRIDE IN INTERACTION WITH PSEVDOMONAS

Application of a mixture of biocontrol agents, as a promising way to control plant pathogens, may have positive or negative effects on their key biocontrol genes expression levels. In this study, interactions between DAPG+ (2,4- diacetylphloroglocinol) and DAPG" P. fluorescens strains and chilinase-producing T. atroviride, indicated that expression of the ech42 was repressed by co-inoculation with the P. fluorescens strains. The repression was observed in the presence of both DAPG* and DAPG" isolates, indicating that DAPG does not play a role in the ech42 expression. In contrast, the nag1 expression did not show significant decrease in DAPCr strains. Interestingly, DAPG+ strains had a positive effect on nag1 expression. Mycelial growth of T. atroviride was reduced in the presence of bacterial isolates. This decline was significantly higher in the presence of DAPG1" isolates in comparison to DAPG" isolates, indicating a possible role of DAPG on the mycelial growth. In conclusion, our results showed that specific interactions between studied biocontrol agents, can affect the expression level of key biocontrol genes. Use