Affectivity evaluation of Bacillus subtilis in controlling eggplant root rot caused by Rhizoctonia solani and Fusarium solani

Abstract

This study included an evaluation of the efficacy of bacteria Bacillus subtilis obtained from Biohealth fertilizer to control the disease of eggplant root rot, caused by Rhizoctonia solani and Fusarium solani. The survey results showed that the disease was observed in all the subjected sites, which were Btera, Maymouna, Saad River and Greta in Misan province. The disease incidence ranged in the four sites between (15-44%). Several pathogenic fungi were isolated and diagnosed, with the most notable and most frequent appearance (R. solani and F. solani) with (35.29 and 29.41%) and (16.91 and 14.18%), respectively. Four isolates were obtained from the fungus R. solani and three isolates from F. solani. All tested fungal isolates caused significant decrease in the percentage of germination seeds in varying proportions, as well as the infection of eggplant root rot with varying proportions. The use of the bacteria (B. subtilis) led to a decrease in the percent severity of disease, and an increase in the soft and dry weight of the vegetative and root groups, as well as a clear increase in the height of plant, leaf number and leaf area of the eggplant. The use of B. subtilis increased the total phenol content (18.4 and 17.8 mg/ml) compared to the control treatment (16.4mg/ml).