journal of kerbala university

This study was conducted to isolate and identify the causative agent for okra root rot disease and control it using some of biological and chemical induction factors. Results showed the presence of some isolates of Fusarium solani in all sites surveyed in Karbala province, representing the Center of Karbala city, Auon and Al-Salamia). It was also revealed that all the pathogenic isolates of F. solani had remarkable effect in reducing the percentage of cress seed germination with superiority of the two isolates Auon 1 and Karbala center 1 that fully prevented growth of plants compared with the germination percentage of the control treatment that was 100%. All F. solani isolates showed significantly reducing in seed germination percentage, and the highest influence seed germination was noticed upon applying the isolate1 (33.33%) compared with the control treatment (100%).
Results also revealed that the antagonistic fungus Trichderma harzianum had remarkable effect on all F. solani isolates with antagonistic ability reached 1 degree according to the Bell standard upon using the antagonistic fungus with the F. solani isolate1 (Auon 1).
Moreover, use of T. harzianum and the chemical induction Bion (B) under glasshouse condition also showed high efficacy against all isolates of F. solani. Highest percentage of seed germination, reached 93%, and less infection percentage as well as highest dry weight and plant length (0.97 g. and 32 cm, respectively) were found upon using T. harzianum against the Fusarium isolate 1. The use of Bion with F. solani 3 gave seed germination of 80%, infection percentage and inhibition percentage of 18% and 20%; however, dry weight (0.77 g.) and plant length 26 cm compared with the control treatment, wherein the seed germination, infection, dry weight and plant length were reached 100%, 0.00%, 0.68 g. and 21.67 cm. respectively.