Rafidain Journal of Science

Abstract

In vitro studies were carried out on the effect of 2 bacterial biopesticide preparations, Pseudomonas fluorescens and Bacillus subtilis on the growth of fungi Fusarium solani, Rhizoctonia solani and Macrophomina phaseolina, causing root rot of okra plants, results revealed a significant effect on reducing the growth of colony diameter and % inhibition with the highest effect noticed with P. fluorescens on the fungus M. phaseolina by 58.43%. The results of greenhouse experiments indicated that both bacterial preparations reduced the percentage of pre and post emergence damping off significantly especially when okra seeds were treated with P. fluorescens and planted in soil contaminated by F. solani (17.79%). Both biopesticides showed a significant increase in the length of shoot and root of okra plants as compared to the untreated seeds planted in contaminated soil. Also an increase in the dry weight of the plants with highest increase was noticed for F. solani reached 0.016 gm with the bacteria P. fluorescens. All seeds treated with P. fluorescens and B. subtilis preparations caused a significant increase in the peroxidase activity as compared to control with the highest increase noticed when seeds were treated with P. fluorescens and planted in M. phaseolina contaminated soil