EFFICACY OF PSEUDOMONAS FLUORESCENS AND IRON CHELATED FE-EDDHA AGAINST FUSARIUM OXYSPORUM F. SP. THE CAUSAL AGENT OF ROOT ROT AND WILT DISEASE ON PEPPER

Abstract

An experiment was conducted to evaluate the biological control activity of Pseudomonas fluorescens PO2 and chelated iron Fe-EDDHA (Fe) at a concentration of 0.5% and the interaction between them for inhibiting Fusarium oxysporum Fo6 on pepper. In vitro, PO2 significantly inhibited the growth of Fo6 with an inhibition rate of 83.33% compared with control, and chelated iron caused a significant decrease for Fo6 with an inhibition rate 66.67% compared with control, while was not affecting the growth of PO2. The results of the pot experiment showed that the treatment (Fo6+PO2+Fe) showed a highest significant difference in reducing the disease incidence and disease severity which amounted to 6.67% compared with control (Pathogen only) (100, 85)% respectively. Also, the treatment (PO2+Fe without the pathogen) was increased the total fresh root and vegetative weight (46.17, 136.8) g respectively and was increase in the dry root and vegetative weight as reached (4.87, 10.07) g respectively compared with control (not inoculated plants) which amounted (12.1, 75.67, 1.83, 5.33) g respectively. In greenhouse experiment the results showed the excellence of the treatment (Fo6+PO2+Fe) in reducing the incidence of infection, which amounted to 10% and the severity of injury amounted to 5.83% compared with the control which recorder to (100, 74)% respectively, as well showed a significant increase in the iron percentage due to response of plant for adding chelated iron into roots with significant differences between treatments. Depending on the results, the use of P. fluorescens with chelated iron can be recommended to control pepper wilt disease caused by F. oxysporum.